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Woodbury Univers ity Course Reader
AR 425.0 ENVIRONMENTAL SYSTEMS
SEMESTER INSTRUCTOR READER CONTENTS Course Syllabus Spring 2008 Course Summary Spring 2008 Semester Project Spring 2008 The Place Of Houses, Charles Moore, Gerald Allen, and Donlyn Lyndon Chapter 5 Yours pages 241 through 266 A Pattern Language: Towns, Buildings, Construction, Christopher Alexander, et. al. Pattern 105 South Facing Outdoors pages 513 through 516 Pattern 107 Wings of Light pages 524 through 530 Pattern 128 Indoor Sunlight pages 614 through 617 Pattern 134 Zen View pages 641 through 643 Pattern 135 Tapestry of Light and Dark pages 644 through 646 Pattern 138 Sleeping to the East pages 656 through 659 Pattern 159 Light on Two Sides of Every Room Light pages 746 through 751 Pattern 161 Sunny Place pages 757 through 760 Pattern 162 North Face pages 761 through 763 Pattern 192 Window Overlooking Life pages 889 through 892 Pattern 221 Natural Doors and Windows pages 1046 through 1049 Pattern 230 Radiant Heat pages 1078 through 1080 Pattern 236 Windows Which Open Wide pages 1100 through 1102 Pattern 238 Filtered Light pages 1105 through 1107 Pattern 250 Warm Colors pages 1153 through 1156 Experiencing Architecture, Steen Eiler Rasmussen Chapter VIII Daylight In Architecture pages 186 through 214 Chapter IX Color In Architecture pages 215 through 223 Cadillac Desert: The American West and Its Disappearing Water, Marc Reisner Introduction A Semidesert with a Desert Heart pages 1 through 14 Chapter I A Country of Illusion pages 15 through 51 Epilogue A Civilization, If You Can Keep It pages 477 through 495 Spring 2008 Scott Glazebrook
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Woodbury Univers ity Course Sy llabus
AR 425.0 ENVIRONMENTAL SYSTEMS UNITS PREREQUISITES SEMESTER INSTRUCTOR DAYS/TIME 3 SC 241, Physics II; AR 281, Design Studio 2B: Program and Space Spring 2008 Scott Glazebrook Monday: Wednesday: "Blue Room" Lecture Lecture 9:00AM to 10:15AM 9:00AM to 10:15AM
ROOM REQUIRED TEXTS
The Building Environment: Active and Passive Control Systems, Third Edition, Vaughn Bradshaw Thermal Delight in Architecture, Lisa Heschong Reader: Environmental Systems (AR 425 Spring 2008) available at University Readers www.universityreaders.com/students RECOMMENDED TEXTS A Pattern Language: Towns, Buildings, Construction, Christopher Alexander Architectural Graphic Standards, Tenth Edition, Charles George Ramsey and Harold Reeve Sleeper Building Construction Illustrated, Third Edition, Francis D. K. Ching and Cassandra Adams Cadillac Desert: The American West and Its Disappearing Water, Marc Reisner Climatic Building Design, Donald Watson, FAIA and Kenneth Labs Deconstructing the Kimbell: An Essay on Meaning and Architecture, Michael Benedikt Design With Climate: Bioclimatic Approach to Architectural Regionalism, Victor Olgyay Experiencing Architecture, Steen Eiler Rasmussen For an Architecture of Reality, Michael Benedikt Heating, Cooling, Lighting: Design Methods for Architects, Second Edition, Norbert Lechner The Place Of Houses, Charles Moore, Gerald Allen, and Donlyn Lyndon The Tao of Architecture, Amos Ih Tiao Chang COURSE DESCRIPTION Human comfort, climate analysis, passive and active systems, heating and cooling, daylighting and acoustics are reviewed. The survey, with a special emphasis on sustainable and green design, provides an understanding of the basic principles and appropriate application and performance of building systems including heating, cooling and ventilation systems; electrical and plumbing distribution systems; lighting, acoustical, energy, waste, fire protection, security, and hazardous material systems. Lecture, three hours a week.
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SPECIFIC LEARNING OUTCOMES
Understanding of the principles of sustainability in making architecture and urban design decisions that conserve natural and built resources, including culturally important buildings and sites, and in the creation of healthful buildings and communities Understanding of the basic principles and appropriate application and performance of environmental systems, including acoustical, lighting, and climate modification systems, and energy use, integrated with the building envelope Understanding of the basic principles of lifesafety systems with an emphasis on egress Understanding of the basic principles and appropriate application and performance of building envelope materials and assemblies Understanding of the basic principles and appropriate application and performance of plumbing, electrical, vertical transportation, communication, security, and fire protection systems Understanding of the fundamentals of building cost, lifecycle cost, and construction estimating
AREAS OF GENERAL DISCUSSION Human comfort is the reason for building. Human comfort is achieved by providing shelter from the unpredictable natural environment, then conditioning the enclosed space to within the very narrow range we find habitable, then providing ancillary systems to bring in necessary resources (water, food, air, etc.) and remove the waste products of human habitation (waste water, CO2, trash, etc.). These goals are achieved through: building envelope and fenestration design; passive and active heating and cooling systems; plumbing, electrical, lighting, and ventilation systems; and fire protection and security systems, to name a few. Successful and synergetic design integration that improves the human condition while preserving precious resources can create interior and exterior, environments that lead to greater satisfaction, health, productivity, security, and welfare. Throughout and interwoven into the course material, concepts and decisions of costs (monetary and natural), responsibility (legal, societal, and environmental), codes (safety and equality), and good design (value) will be discussed. Topics of discussion will include: · Making a comprehensive analysis and evaluation of a building, building complex, or urban space · Providing a coherent rational for the programmatic and formal precedents employed in the conceptualization and development of architecture and urban design projects · Western architectural canons and traditions in architecture, landscape, and urban design, as well as the climatic, technological, socioeconomic, and other cultural factors that have shaped and sustained them · Introduction to nonWestern traditions in architecture, landscape, and urban design · Responding to natural and built site characteristics in the development of a program and design of a project · Basic principles that inform the design of building envelope systems · Assessing, selecting, and integrating structural systems, environmental systems, and building service systems into building design · Architects' legal responsibilities with respect to public health, safety, and welfare; property rights; zoning and subdivision ordinances; building codes; accessibility and other factors affecting building design, construction, and architecture practice
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Codes, regulations, and standards applicable to a given site and building design, including occupancy classifications, allowable building heights and areas, allowable construction types, separation requirements, occupancy requirements, means of egress, fire protection, and structure Principles, conventions, standards, applications, and restrictions pertaining to the manufacture and use of construction materials, components, and assemblies
NAAB PERFORMANCE CRITERIA Levels of accomplishment Understanding: assimilation and comprehension of information. Students can correctly paraphrase or summarize information without necessarily being able to relate it to other material or see its fullest implications. Ability: skill in relating specific information to the accomplishment of tasks. Students can correctly select the information that is appropriate to a situation and apply it to the solution of specific problems. NAAB CRITERIA SATISFIED 15 19 20 21 22 25 Sustainable Design Environmental Systems Life Safety Building Envelope Systems Building Service Systems Construction Cost Control understanding understanding understanding understanding understanding understanding
NAAB CRITERIA DISCUSSED 4 9 10 15 20 22 23 24 25 Critical Thinking Skills Use of Precedents Western Traditions Site Conditions Building Envelope Systems Building Systems Integration Legal Responsibilities Building Code Compliance Building Materials and Assemblies
INSTRUCTIONAL PROCESS New information will be introduced during the both the Monday and Wednesday lecture periods. Outofclass assignments will be assigned to be completed for submittal on the following scheduled lecture day (with some exception based on difficulty of assignment); significant effort is expected to complete outofclass assignments. Lecture sections may include quizzes and inclass assignments to test student's retention of information introduced in the lecture period, in the assigned readings, and in outofclass assignments. Missed lectures, quizzes, inclass assignments, exams, and outofclass assignments cannot be "madeup" without arrangement in advance of class period. Topicrelevant field trips may be scheduled periodically during regular class time  if at all possible. Field trips not scheduled during class time will be considered "optional", although highly recommended. Every effort will be made to schedule field trips on Mondays. All attending students should come prepared as required (e.g. wearing closedtoed shoes on a construction site, necessary University forms completed and submitted, etc.). Transportation to the field trip site will be the responsibility of the individual student. Case studies and other coursespecific material may be presented by guest lecturers.
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ASSESSMENT OF STUDENT PERFORMANCE Outofclass Assignments: Quizzes/Inclass Assignments: Semester Project: Midterm Project 10% Final Project 15% Final Exam: Total: Total Semester Score: 97100% 9396% 9092% 8789% 8386% 8082% 7779% 7376% 7072% 6769% 6366% 6062% < 60% POLICY OF PROJECT RETENTION The university reserves the right to retain student work for archival purposes. Projects/models, assignments, and exams will be kept at the department's discretion for this purpose. Final Semester Project and Final Exams will be retained. STUDENT RESPONSIBILITY It is the responsibility of the student to attend class/studio sessions and to work in class/studio. Woodbury University has established clear and appropriate grading and administrative guidelines. They will be followed in this class, except as amended. Students should be familiar with the various policies as stated in the Woodbury University catalog. SEMESTER COURSEWORK This is a tentative description of the coursework to be completed throughout the semester. This listing may be revised to reflect current topical and timely materials as influenced by the profession. OUTOFCLASS ASSIGNMENTS (25%) 5 points each 50 points total 1 2 3 4 5 6 7 8 9 10 Solar Geometry Thermal Comfort Climate Challenge (presentation) Beginning Thermodynamics Daylighting Advanced Thermodynamics Active Mechanical and Lighting Systems Active Electrical, Life Safety Systems, and Tertiary Systems Water Resource Challenge (presentation) Water Supply and Removal Systems
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25% 25% 25%
25% 100% A+ A AB+ B BC+ C CD+ D DF
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QUIZZES (25%) 10 points each 50 points total Quiz 1 Quiz 2 Quiz 3 Quiz 4 Quiz 5 Solar Geometry and Thermal Comfort Climate and Beginning Thermodynamics Daylighting and Advanced Thermodynamics Active Mechanical and Lighting Electrical, Life Safety Systems, Tertiary Systems, Regional Water, and Water Systems
SEMESTER PROJECT (25%) 50 points total The purpose of the semester project is to apply knowledge acquired in class towards "realworld" experiences; expand learning potential through active participation in design of building environmental systems; to demonstrate learned comprehension of presented course material for course evaluation. The semester project is an INDIVIDUAL project to design a simple oneroom building to test thermodynamically and for appropriate illumination characteristics; and to schematically incorporate appropriate active mechanical, lighting, electrical, plumbing, and fire protection systems. A) A cursory evaluation and concept design by each student will be required, detailed engineering analysis will not be. B) Each student is to create a unique building design and is to prepare their report independently. Working together to reinforce understanding of material is encouraged. The semester project report is to be bound and clearly presented in written and graphic form, utilizing written and graphic techniques as necessary to fully describe your project's physical and performance characteristics. Evaluation will be based on understanding of course material, accuracy, clarity, and quality of presentation. Calculations may be included in a project appendix if desired (please reference calculations in project report body). Do not limit yourselves to the required texts for this course utilize the recommended texts list and/or any other relevant material as you see necessary in completing your project (bibliography and end/footnotes are required for referenced materials and data). Each outofclass assignment directly relates the different technical components to be prepared for the Semester Project. Part 1: (10%) 20 points building design, solar geometry, climate, thermal comfort, beginning thermodynamics Part 2: (15%) 30 points daylighting, advanced thermodynamics, active systems, water, tertiary systems EXAM (25%) 50 points total Final Exam Summary of all course material (all lectures, field trips, reading, assignments, quizzes)
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TENTATIVE SCHEDULE
The rights to modify, change, reschedule, omit, delete, or add anything is reserved. Week 1 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 2 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 3 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 4 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 5 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 6 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 7 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Monday (1/14) Introduction, Solar Geometry Semester Project Thermal Delight: Preface, Necessity Wednesday (1/16) Solar Geometry 1 Solar Geometry Thermal Delight: Delight, Affection Thermal Delight: Preface, Necessity Wednesday (1/23) Thermal Comfort 1 Solar Geometry Thermal Delight: Sacredness Thermal Delight: Delight, Affection Monday (1/28) Thermal Comfort 2 Thermal Comfort The Place of Houses Thermal Delight: Sacredness Monday (2/4) Beginning Thermodynamics 3 Climate Challenge The Building Environment: ch. 2 The Building Environment: ch. 1 Quiz 1 Monday (2/11) Beginning Thermodynamics 4 Beginning Thermodynamics The Building Environment: ch. 3 The Building Environment: ch. 2 Monday (2/18)  Holiday Wednesday (2/13) Beginning Thermodynamics 4 Beginning Thermodynamics A Pattern Language: patt. 105  128 The Building Environment: ch. 3 Wednesday (2/20) Daylighting Wednesday (1/30) Climate 3 Climate Challenge 2 Thermal Comfort The Building Environment: ch. 1 The Place of Houses Wednesday (2/6) Beginning Thermodynamics
Monday (1/21)  Holiday
A Pattern Language: patt. 134  192 A Pattern Language: patt. 105  128 Monday (2/25) Daylighting Midterm Semester Project A Pattern Language: patt. 221  250 A Pattern Language: patt. 134  192 Quiz 2 Wednesday (2/27) Daylighting 5 Daylighting Experiencing Architecture: ch. VIII A Pattern Language: patt. 221  250
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Week 8 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 9 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 10 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 11 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 12 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 13 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 14 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam
Monday (3/3) Daylighting 5 Daylighting Experiencing Architecture: ch. IX Experiencing Architecture: ch. VIII Monday (3/10) Advanced Thermodynamics 6 Advanced Thermodynamics The Building Environment: ch. 7 The Building Environment: ch. 5 Monday (3/17)  Break
Wednesday (3/5) Advanced Thermodynamics
The Building Environment: ch. 5 Experiencing Architecture: ch. IX Wednesday (3/12) Advanced Thermodynamics 6 Advanced Thermodynamics The Building Environment: ch. 6 The Building Environment: ch. 7 Quiz 3 Wednesday (3/19)  Break
Monday (3/24) Active Mechanical and Lighting
Wednesday (11/9) Active Mechanical and Lighting 7 Active Mechanical & Lighting The Building Environment: ch. 8 The Building Environment: ch. 6
Monday (3/31) Active Mechanical and Lighting 7 Active Mechanical & Lighting The Building Environment: ch. 9 The Building Environment: ch. 8 Quiz 4 Monday (4/7) Active Electrical and Life Safety 8 Active Electrical & Life Safety The Building Environment: ch. 12 The Building Environment: ch. 11 Monday (4/14) Water Resources 9 Water Resource Challenge Cadillac Desert: Introduction, ch. 1 The Building Environment: ch. 13
Wednesday (4/2) Active Electrical and Life Safety
The Building Environment: ch. 11 The Building Environment: ch. 9 Wednesday (4/9) Water Resources 8 Active Electrical & Life Safety The Building Environment: ch. 13 The Building Environment: ch. 12 Wednesday (4/16) Plumbing Systems 10 Water Supply and Removal 9 Water Resource Challenge Cadillac Desert: Epilogue Cadillac Desert: Introduction, ch. 1
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Week 15 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 16 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam Week 17 Lecture Assignment (issued) Assignment (due) Reading (issued) Reading (due) Quiz/Exam
Monday (4/21) Plumbing Systems 10 Water Supply and Removal Cadillac Desert: Epilogue Quiz 5 Monday (4/28) Studio Finals
Wednesday (4/23) Summary Final Semester Project
Wednesday (4/30) Studio Finals
Monday (5/5) No class
Wednesday (5/5)
Final Exam
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E n v i r o n m e n t a l Summary
I. Solar Geometry
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Solar Geometry is the everchanging angle of the Sun relative to the observed location on the Earth. Plane of the Ecliptic is the plane upon which the Earth orbits the sun. Obliquity of the Ecliptic is the changing angle of the Earth's rotational axis to a perpendicular drawn through the Plane of the Ecliptic.  Maximum Obliquity of the Ecliptic is at the two Solstices, at an angle of 23.5°. Summer Solstice is approximately June 21st Winter Solstice is approximately December 21st  Minimum Obliquity of the Ecliptic is at the two Equinoxes, as an angle of 0°. Spring Equinox is approximately March 21st Fall Equinox is approximately September 21st Solar Angle is dependent on time of year (Solar Calendar), time of day (Solar Time), and Latitude  Solar Calendar begins on the Winter Solstice.  Solar Time begins when the Sun is at it's peak Altitude and zero Azimuth for the day.  San Diego's Latitude is 32°N42'54" (thirtytwo degrees North, 42 minutes, 54 seconds). Solar Beam is the implied direction of the Sun's rays and strength of those rays in BTU/hr·sf.  All of the Sun's rays are assumed to arrive to the Earth's surface parallel to one another. Solar Constant (o) is the radiant flux on a surface facing the Sun on the Earth's orbit outside the atmosphere and is assumed to be a constant 429 BTU/hr·sqft.  Adjusted for atmospheric attenuation (thickness, density, composition, etc.) to derive the Solar Beam Intensity (B), also known as the Direct Solar Normal. Solar Noon is defined by the instant when the Sun is highest in the sky on a particular day. Direct Solar Normal (B) is the total solar energy measured perpendicular ("normal") to the solar beam vector, measured in BTU/hr·sqft. Diffuse Solar Radiation is the radiation reflected and refracted by the atmosphere and objects that causes the solar rays to change direction. Insolation (S) is component of the Direct Solar Normal plus the Diffuse Solar Radiation normal (perpendicular) to the surface being examined. Zenith (Z) is the vertical angle of the Sun from vertical.  cos(Z) = z Altitude () is the vertical angle above the horizontal of the Sun's location.  sin() = z Azimuth () is the horizontal angle of the Sun from due South (positive is East, negative is West).  s = cos()·cos()  e = cos()·sin() Solar Sphere is the assumed possible path of the Sun across the sky (the Sun appears to traverse the sky on this sphere).  When using the Solar Protractor, the solar sphere is assumed to have a radius of 1  z 2 + s 2+ e2 = 1 Solar Protractor is a device used to determine solar angle at Latitude. To read the solar protractor:  Align the rotating bezel alignment line (MarchSeptember) to the Latitude designation along the solar sphere curve (shown here aligned to 32°North Latitude for San Diego)  Find the month of interest on the bezel.  Lines with month name are for the 21st of the month (solar month).  Find time of interest on the month of interest line.  Note solar symmetry about solar noon.  From the intersection of solar month and solar time, track a vertical line down to the horizontal axis and read the South or North value = s.  From the intersection of solar month and solar time, track a horizontal line across to the vertical axis and read the Zenith value = z.
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Rotate the bezel around the pivot point to align the intersection of solar month and solar time to the vertical axis. Track a horizontal line to the solar sphere curve on the side the intersecting lines originally occurred; when hitting the solar sphere, track a vertical live down to the horizontal axis to read the East value = e. Check values by using the equation: z2 + s2+ e2 = 1
Determine the South, Zenith, and East solar angle components at 2PM on February 21 for San Diego, California (32°North Latitude) using the Solar Protractor. s = 0.62 z = 0.61 e = 0.49 (negative means West) 0.622 + 0.612+ 0.492 = 1
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Graph the South, Zenith, and East solar angle components at 2PM on February 21 for San Diego, California (32°North Latitude) using the Solar Protractor. Points are graphed below for the solar month and solar time designated. Note symmetry about solar noon, 2PM and 10AM are "identical" but graphed on opposite sides of the Zenith and South lines (West is negative East).
Solar Protractor Interpolation reading times and days not specifically identified on the bezel:  Align the rotating bezel alignment line (MarchSeptember) to the Latitude designation along the solar sphere curve (shown here aligned to 32°North Latitude for San Diego)  Find the month of interest on the bezel.  Lines with month name are for the 21st of the month (solar month).  The space between month lines are divided by 4 for approximately 4 weeks per month.  For example, the 7th of the month is the middle tick 2 weeks from the 21st.  Find time of interest on the month of interest line.  Note solar symmetry about solar noon.  Times between whole hours can be extrapolated by quarterhour (15 minute) tick marks.  For example, 15 minutes after the hour is the first tick towards the next hour.  From the intersection of solar month and solar time, track a vertical line down to the horizontal axis and read the South or North value = s.  From the intersection of solar month and solar time, track a horizontal line across to the vertical axis and read the Zenith value = z.  Rotate the bezel around the pivot point to align the intersection of solar month and solar time to the vertical axis. Track a horizontal line to the solar sphere curve on the side the intersecting lines originally occurred; when hitting the solar sphere, track a vertical live down to the horizontal axis to read the East value = e.  Check values by using the equation: z2 + s2+ e2 = 1
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Graph the South, Zenith, and East solar angle components throughout the day on February 7 and July 7 for San Diego, California (32°North Latitude) using the Solar Protractor.
Design an exterior sun shading device to protect a window from solar exposure between 11AM and 1PM on July 7 for San Diego, California (32°North Latitude) using the Solar Protractor.
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II. Thermal Comfort and Climate Thermal Comfort Zone is between 70°F and 78°F for sedentary occupancies, between 69°F and 76°F for active occupancies. It is also dependent upon humidity in the air, radiant surface temperatures, clothing levels and metabolic rates of occupants.  California Building Code (CBC) establishes a requirement to maintain a 70°F temperature through heating at three feet above the floor of an occupied space (for most occupancies). This doesn't consider health factors due to overheating (heat stroke) and dehydration.  If your building passively (floats) develops a temperature outside the desired comfort range, there are two options: mechanically adjust the temperature or redesign the building to change the heat gain. Psychrometrics is the study of the physical and thermal properties of air and water vapor mixtures. Atmospheric Air contains water vapor, pollutants, and gases such as nitrogen, oxygen, and carbon dioxide. Dry air is referred to as air devoid of water vapor and pollutants. Moist air is the mixture of dry air and vapor. Vapor is gaseous water suspended in air. Drybulb temperature is that of an air sample, as determined by an ordinary thermometer, the thermometer's bulb being dry. Wetbulb temperature is that of an air sample after it has passed through a constantpressure, ideal saturation process, that is, after the air has passed over a large surface of liquid water in an insulated channel. In practice, this is the reading of a thermometer whose sensing bulb is covered with a wet sock evaporating into a rapid stream of the sample air a "sling psychrometer". Dew Point temperature is that at which a moist air sample at the same pressure would reach water vapor saturation. At this saturation point, water vapor would begin to condense into liquid water fog or (if below freezing) solid frost, as heat is removed; also known as Saturation Temperature. Relative Humidity is the ratio of the fraction of water vapor to the fraction of saturated moist air at the same temperature and pressure, enumerated as a percentage. Humidity Ratio is the proportion of the mass of moisture present in a unit mass of air, measured in grains of moisture per pound of dry air or pounds of vapor per pounds of dry air. Enthalpy is the sum of the internal energy of a thermodynamic system (Sensible and Latent Heat), also called heat content per unit mass. These values correspond to the saturated state and are to be read parallel to Wetbulb Temperature values. Enthalpy is measured in BTU per pound of dry air. Psychrometric Chart interrelates the five major factors in describing the conditions of Atmospheric Air. Psychormetric Charts are based on atmospheric pressure for locations below 2,000 feet altitude, the common assumption is to use the chart calibrated for sea level. How to read the five major values presented on the chart:  Drybulb temperature is determined along the horizontal axis and is tracked vertically.  Dew Point temperature is determined along the left curve (Saturation Curve) at 100% Relative Humidity, and is tracked horizontally.  Wetbulb temperature is determined along the left curve (Saturation Curve) at 100% Relative Humidity, and is tracked diagonally from upper left to lower right.  Relative Humidity is charted as curving (hyperbolic) lines drawn asymptotically with respect to the saturation curve at 100% Relative Humidity.  Humidity Ratio is marked on the vertical axis.  Enthalpy lines slope from the upper left to the lower right and are read on the left. Knowing any two of the five values allows the acquisition of the other three.
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III. Thermodynamic Principals
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Thermodynamics is the study of the movement of energy and how energy instills movement. Zeroth law of thermodynamics  If two thermodynamic systems are separately in thermal equilibrium with a third, they are also in thermal equilibrium with each other (If A=B, and B=C, A=C). First law of thermodynamics  The change in the internal energy of a closed thermodynamic system is equal to the sum of the amount of heat energy supplied to the system and the work done on the system (also known as "Conservation Of Energy") Second law of thermodynamics  The total entropy of any isolated thermodynamic system tends to increase over time, approaching a maximum value. Third law of thermodynamics  As a system asymptotically approaches absolute zero of temperature all processes virtually cease and the entropy of the system asymptotically approaches a minimum value. Heat is a measure of the amount energy, measured in British Thermal Units (BTU)s, where one BTU equals the energy required to raise 1 pound of water 1 degree Fahrenheit. Temperature is a measure of the degree of heat intensity, the difference of which defines the potential for heat (energy) to move from the warmer to the colder (higher to lower) Entropy is a quantitative measure of organization (>Entropy = <Organization) Convection heat transfer through motion Conduction heat transfer through materials Radiation longwave electromagnetic dispersion (IR) Evaporation/Condensation heat of vaporization, heat of fusion (phase changes solid>liquid, liquid>gas, gas>liquid, liquid>solid, plasma) IV. Heat Gain, Mean Radiant Temperature, Steady State Flux (lowercase variable) is the measurement of heat gain per time period per area of consideration  technically and scientifically speaking, a "flux" is a measurement per area of consideration  e.g. "q" BTU/hr·sqft Rate (upper case variable) is the measurement of heat gain per time period  e.g. "Q" BTU/hr Sensible heat is also known as "explicit heat", heat that can be explicitly felt.  heat that raises temperature  e.g. 1 BTU is the amount of energy required to raise 1 pound of water 1 Fahrenheit degree Latent heat is also known as "implicit heat", because it is implied and not directly observable.  heat that changes phase of material  e.g. 970 BTUs is the amount of energy required to change 1 pound of water to vapor Enthalpy is the total energy is a system (sum of Sensible and Latent heat energy). Mean Radiant Temperature (MRT) effects the rate of radiative heat transfer to/from the observer. Calculate MRT for a space in two dimensions. (T·) T = Temperature (°F) MRT = = Observer's angle of exposure 360° MRT = MRT = (68°F·90°) + (70°F·160°) + (50°F·110°) 360° 63.40°F
This is a twodimensional representation of a threedimensional phenomena. The observer's Mean Radiant Temperature (temperature sensation) is 63.40°F (regardless of air temperature)
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Resistivity (r) is material specific the number of hours required for 1 BTU to penetrate 1 square foot of the specific material for each Fahrenheit degree temperature difference separated by 1 inch of the material (hr·sqft·°F/BTU·in). r = 1/k Resistance (R) is material and quantity specific the number of hours required for 1 BTU to penetrate 1 square foot of the specific material of a specific thickness at each Fahrenheit degree of temperature difference (hr·sqft·°F/BTU). R = r·x (x is depth of material in direction of heat transfer in inches) R = 1/C = x/k = r·x Conductivity (k) is material specific the depth of BTUs penetrating a material per hour, per square feet of material, per number of Fahrenheit degrees of temperature difference (BTU·in/hr·sqft·°F). k = 1/r Conductance (C) is material and quantity specific the number of BTUs penetrating a material of particular thickness per hour, per square feet of material, per number of Fahrenheit degrees of temperature difference (BTU/hr·sqft·°F). C = k/x (x is depth of material in direction of heat transfer in inches) C = 1/R = 1/r·x = k/x = C RValue is the most commonlyknown value associated with heat energy transfer, used to describe quality of building insulation and minimum standards for wall assembly overall resistance to heat energy transfer. Rvalue is generally applied to assemblies of building materials, and can be thought of as the summation of the individual components' individual resistances. Minimum standards for design and construction are established by building and energy codes. Rvalue = R1 + R2 + R3 + ... Rn = Rn UValue describes as assembly of building materials' ability to conduct heat energy. It is the value assigned to an assembly of materials that make a composite; commonly associated with building products like window and door assemblies. While UValue can be thought of as the summation of the individual components' individual conductances, the individual conductances are not additive. Uvalue C1 + C2 + C3 + ... Cn Cn Calculate UValue of wall assembly (include air film coefficients). Given: A = 5/8" gypsum board = R = 0.56 hr·sqft·°F/BTU B = 11/2" air space = R = 1.02 hr·sqft·°F/BTU C = 6" concrete = R = 0.48 hr·sqft·°F/BTU D = 2" rigid insulation = r = 6.50 hr·sqft·°F/BTU·in E = 1" exterior plaster = r = 0.20 hr·sqft·°F/BTU·in Convert r to R (R = r·x): D = (6.50 hr·sqft·°F/BTU·in) · (2 in) = 13.00 hr·sqft·°F/BTU E = (0.20 hr·sqft·°F/BTU·in) · (1 in) = 0.20 hr·sqft·°F/BTU Determine air film coefficients (hi and ho): hi = inside air film (still) = 0.68 hr·sqft·°F/BTU ho = outside air film (7.5 mph) = 0.18 hr·sqft·°F/BTU Add Rs (Rvalue = Rn): Rvalue = 0.68 hr·sqft·°F/BTU 0.56 hr·sqft·°F/BTU 1.02 hr·sqft·°F/BTU 0.48 hr·sqft·°F/BTU 13.00 hr·sqft·°F/BTU 0.20 hr·sqft·°F/BTU 0.18 hr·sqft·°F/BTU 16.12 hr·sqft·°F/BTU Find the assembly conductance (Uvalue = 1/R): Uvalue = 1/16.12 hr·sqft·°F/BTU = 0.06 BTU/hr·sqft·°F
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Steady State assumes instantaneous heat energy transfer assumes knowledge of both interior and exterior surface or air temperatures, ignores time, assumes 100% transfer, assumes an isolated (closed) system, and is based on the First and Second Laws of Thermodynamics and is a necessary assumption for calculation. Heat Balance assumes the sum of all energy inputs and subtractions results in a net zero energy gain within the system or a "balance" of all energy and is based on the First and Second Laws of Thermodynamics.  Rate of conductive heat energy transfer = Q = U·A·(T1T2) = BTU/hr  Flux of conductive heat energy transfer = q = U·(T1T2) = BTU/hr·sqft  Basic Heat Balance Equation: Q1 + Q2 + Q3 + ... Qn = 0 (q1 + q2 + q3 + ... qn = 0)  Derivative Heat Balance Equation: Q + M + H = 0 (q + m + h = 0) M (and m) = mechanical demand (`+' for heating, `` for cooling) H (and h) = heat gain (solar/radiant, equipment, occupancy, infiltration) V. Temperature Profile, Heat Balance, Solar Absorptance Temperature Profile Diagram describes the temperatures experienced within a material or assembly based on the material's or assembly's conductance and the surface temperatures of the material (assuming steady state conditions and twodimensional analysis). This is the basis for solving for conductive heat energy transfer. Calculate Flux of a threecomponent solid wall assembly (ignore air film coefficients). Given: R1 = rigid insulation = 6.5 hr·sqft·°F/BTU R2 = concrete = 0.48 hr·sqft·°F/BTU R3 = gypsum board = 0.56 hr·sqft·°F/BTU Known: q1 = q2 = q3 (First Law of Thermodynamics) q = C·(T1T2) (U and C are interchangeable) Equate: q1 = C1· (90°F  T2) q2 = C2· (T2 T3) q3 = C3· (T3 70°F) 3 equations and 3 unknowns Divide each side by unique `C' values: q1/C1 = (90°F  T2) q2/C2 = (T2  T3) q3/C3 = (T3  70°F) Add both sides of equations vertically: q1/C1 + q2/C2 + q3/C3 = 90°F  T2 + T2  T3 + T3  70°F Extract `q' (q1 = q2 = q3) and cancel `T's: q·(1/C1 + 1/C2 + 1/C3) = 90°F  70°F Convert conductances to resistances: q·(R1 + R2 + R3) = 20°F Isolate flux (`q'): q = (20°F)/(R1 + R2 + R3) Enter resistance values: q = (20°F)/(7.54 hr·sqft·°F/BTU) Solve: q = 2.65 BTU/hr·sqft 2.65 BTUs of heat energy will pass through this assembly in 1 hour per square foot of surface area with a specific 20 F° temperature difference.
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Solar Constant (o) is the radiatiant flux on a surface facing the Sun on the Earth's orbit outside the atmosphere and is assumed to be a constant 429 BTU/hr·sqft. Solar Beam Intensity (B) is the total solar energy measured perpendicular ("normal") to the solar beam vector, measured in BTU/hr·sqft. Solar Insolation (S) is the perpendicular to the surface component of the solar energy striking a surface, measured in BTU/hr·sqft. Absorptance (a) is the percentage of radiant energy striking a surface absorbed by the surface, measured perpendicular to the surface. Conductive Solar Heat Gain (qsolar) is the energy striking the surface that is absorbed and is calculated by multiplying the Solar Insolation by the surface Absorptance (qsolar = aS = a·S) Heat Balance identifies that for any given point in a defined closed (Steady State) system the sum of all heat energy transfers must add up to zero, applied to spaces ("Cavities") or assemblies. Calculate surface temperatures of single component wall assembly (include air film coefficients). Given: C2 = 2.08 BTU/hr·sqft·°F (R2 = 0.48 hr·sqft·°F/BTU) S = 300 BTU/hr·sqft a = 0.6 To = 90°F (temperature of outdoor air) Ti = 70°F (temperature of indoor air) C1 is outside air film C3 is inside air film Determine air film coefficients (R1 and R3): ho = 0.25 hr·sqft·°F/BTU (outdoor air film coefficient) hi = 0.68 hr·sqft·°F/BTU (indoor air film coefficient) Determine heat balance equation starting with T2: qsolar + qoutsideair + qwall + qindoorair = 0 aS + C1·(To T2) + C2·(T3 T2) + C3·(Ti T3) = 0 Reduce unknown temperature variables to one (T2): qsolar + qoutsideair + qwall+insideair= 0 aS + C1·(To T2) + C2·(Ti T2) = 0 Calculate conductance (C) values: C1 = 1/ho = 4.00 BTU/hr·sqft·°F C2 = 1/R2 = 2.08 BTU/hr·sqft·°F C3 = 1/hi = 1.47 BTU/hr·sqft·°F C2 + C3 = 1/R2 + 1/hi = 0.86 BTU/hr·sqft·°F Calculate individual components of heat gain: qsolar = a·S = 0.6 · 300 BTU/hr·sqft = 180 BTU/hr·sqft qoutsideair = 4.00 BTU/hr·sqft·°F · (90°F  T2) qwall+insideair = 0.86 BTU/hr·sqft·°F · (70°F  T2) Solve for T2: 180 BTU/hr·sqft + [4.00 BTU/hr·sqft·°F · (90°F  T2)] + [0.86 BTU/hr·sqft·°F · (70°F  T2)] = 0 180 BTU/hr·sqft + 360 BTU/hr·sqft (4.00 BTU/hr·sqft·°F · T2) + ... ... 60.20 BTU/hr·sqft (0.86 BTU/hr·sqft·°F · T2) = 0 600.20 BTU/hr·sqft  4.86 BTU/hr·sqft·°F · T2 = 0 4.86 BTU/hr·sqft·°F · T2 = 600.20 BTU/hr·sqft T2 =123.46°F Solve for T3: qsolar + qoutsideair + qwall = 0 aS + C1·(To T2) + C2·(T3 T2) = 0 180 BTU/hr·sqft + [4.00 BTU/hr·sqft·°F · (90°F  123.46°F)] + ... ... [2.08 BTU/hr·sqft·°F · (T3  123.46°F)] = 0 180 BTU/hr·sqft  133.84 BTU/hr·sqft + (2.08 BTU/hr·sqft·°F · T3)  256.80 BTU/hr·sqft = 0 210.64 BTU/hr·sqft + 2.08 BTU/hr·sqft·°F · T3 = 0 2.08 BTU/hr·sqft·°F · T3 = 210.64 BTU/hr·sqft T3 = 101.27°F (this is the interior surface temperature used in MRT calculations)
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VI. Heat Capacitance, Infiltration, and Ventilation Specific Heat Capacitance (cs) is a material's unique capacity to absorb heat energy.  Measured in BTU/lb·°F Heat Capacitance (Ch) is the ability for a particular composition to store heat.  Measured in BTU/°F  Ch = cs·m (m = mass) Energy (E) stored within a specific sample of material is dependent upon the material's temperature and Heat Capacitance (temperature must be consistent throughout).  E = C h·T Calculate Energy in a material. Given: 100 pounds of concrete at 100°F cs of concrete = 0.20 BTU/lb·°F Solve for Heat Capacitance: Ch = cs·m Ch = 0.20 BTU/lb·°F · 100 lbs Ch = 20 BTU/°F Solve for Energy: E = Ch·T E = 20 BTU/°F · 100°F E = 2,000 BTU Calculate Temperature of a material. Given: 100 pounds of concrete E of concrete = 500 BTU Solve for Temperature: T = E/Ch T = 500 BTU/(20 BTU/°F) T = 25 °F Ventilation is the desired exchanges of interior air for exterior air.  Ventilation results in heat transfer through convection. Infiltration is the undesired exchanges of interior air for exterior air.  Infiltration is expected; buildings that do not exchange interior air for exterior air will become "sick" ("sick building syndrome"), oxygen is depleted and wastes are not removed.  Infiltration results in heat transfer through convection.  Infiltration effects of building assemblies are considered in their prescribed UValues (e.g. window assemblies UValue is adjusted for Infiltration). Heat Transfer through Ventilation and Infiltration is calculated similar to convective and radiative heat energy transfer, but is dependent upon Specific Heat Capacitance and density of the moving air.  Rate of Infiltration or Ventilation (convective) heat energy transfer = Q = ·cs·(dV/dt)·(T1T2) = air density (lbs/ft3) cs = Specific Heat Capacitance (BTU/lb·°F) ·cs = 0.018 BTU/ft3·°F (assumed constant at sea level) dV/dt = Air Exchange Rate (ft3/hr) Air Exchange Rate is the rate at which one complete exchange of interior aur is exchanged for exterior air in a Cavity.  e.g. for a 1,000 ft3 cavity, 1 air change per hour = 1,000 ft3/hr  e.g. for a 1,000 ft3 cavity, 1 air change per two hours = 1,000 ft3/2 hr = 500 ft3/hr  e.g. for a 1,000 ft3 cavity, ½ air change per hour = 500 ft3/hr  1 air change per hour due to infiltration is considered "standard" construction techniques, ½ air changes per hour due to infiltration is considered "tight".
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Calculate Heat Energy Transfer due to infiltration. Given: Volume = 1,000 ft3 Tight construction Exterior air temperature = 100°F Interior air temperature = 70°F Determine air exchange rate: dV/dt = 1,000 ft3 · (0.5/hr) = 500 ft3/hr Solve for heat energy transfer: Q = ·cs·(dV/dt)·(T1T2) Q = (0.018 BTU/ft3·°F) · (500 ft3/hr) · (100°F  70°F) Q = 270 BTU/hr Infiltration rates are assumed during design, and often confirmed in the field during building commissioning a process of using fans to pressurize the building and test for "leaks". This test is accomplished during "building commissioning" prior to occupancy. Postoccupancy evaluations are also recommended as the building "settles". Heat Transfer through Ventilation and Infiltration may also be calculated per the textbook equation: Q = 1.08 · CFM · T. This equation is "normalized" by the mechanical engineering industry to simplify calculations, but has no basis in the actual process of heat transfer and thus is not as informative about the process (thought the results are the same). Calculate Heat Energy Transfer due to infiltration. Given: Volume = 1,000 ft3 Tight construction Exterior air temperature = 100°F Interior air temperature = 70°F Determine air exchange rate: CFM = 1,000 ft3 · (0.5/hr) = 500 ft3/hr = 8.33 CFM (Cubic Feet per Minute) Solve for heat energy transfer: Q = 1.08 · CFM · T Q = 1.08 · 8.33 CFM · (100°F  70°F) Q = 269.89 BTU/hr While this method works, units are not conserved and variables in air density (altitude) and specific heat capacitance (water vapor content) cannot be accounted for. VII. Daylighting and Zero Order Analysis Incident Light striking a surface is: reflected, absorbed, and transmitted (if material is translucent). These three components are expressed as fractions of the incident light (coefficients of reflectance, absorption, and transmittance).  r = R/I = reflectance a = A/I = absorptance t = T/I = transmittance  1=r+a+t  Light that enters a room falls incident onto the surfaces enclosing the space of the room (cavity). Upon incidence the light is partially reflected, absorbed, and transmitted out in a proportion to the respective coefficients of the surface. The absorbed component raises the temperature of the surface. The reflected component will fall incident on another surface enclosing the space; upon incidence on another surface the reflected light will split into the three components again with similar results. The transmitted component will escape the space. This phenomenon will continue until all of the initial light is either absorbed by the surfaces enclosing the room or it is transmitted out of the space.  Heat energy is measured in Imperial Units (BTU), Light Energy is measured in SI units (Watthours), to convert between the two, the equivalency is: 1 BTU/hr·sf = 3.15 Watts/m2.
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Efficacy (e) is the ability to produce a desired amount of a desired effect. In lighting design, "efficacy" refers to the amount of visible illumination produced by a lamp (a light bulb or other light source), usually measured in lumens, as a ratio of the amount of energy consumed to produce the illumination, usually measured in Watts. This is not to be confused with efficiency which is always a dimensionless ratio of output divided by input, which for lighting relates to the Watts of visible energy as a ratio of the energy consumed in Watts (Watt/Watt). The maximum efficacy possible is 683 lumens/Watt with 100% of the energy input being converted to illuminance.  Efficacy of sunlight = e = 114 lumens/Watt = 36 footcandles per BTU/hr·sf  Efficacy of fluorescent = e = 65 lumens/Watt = 20 footcandles per BTU/hr·sf  Efficacy of incandescent = e = 14 lumens/Watt = 4 footcandles per BTU/hr·sf Lumen (lm) is the SI unit of luminous flux, a measure of the perceived power of light. Luminous flux differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light. If a light source emits one candela of luminous intensity into a solid angle of one steradian, the total luminous flux emitted into that solid angle is one lumen. Alternatively, an isotropic onecandela light source emits a total luminous flux of exactly 4 lumens. The lumen can be thought of casually as a measure of the total "amount" of visible light emitted. Lux (lx) is the SI unit of illuminance. It is used in photometry as a measure of the intensity of light, with wavelengths weighted according to the luminosity function, a standardized model of human brightness perception. Lux is a derived unit based on lumen, and lumen is a derived unit based on candela.  1 lx = 1 lm/m2  The difference between the lux and the lumen is that the lux takes into account the area over which the luminous flux is spread. 1000 lumens, concentrated into an area of one square meter, lights up that square meter with an illuminance of 1000 lux. The same 1000 lumens, spread out over ten square meters, produces a dimmer illuminance of only 100 lux. Footcandle (sometimes footcandle; abbreviated fc, lm/ft², or sometimes ftc) is a nonSI unit of illuminance or light intensity widely used in photography, film, television, and the lighting industry. The unit is defined as the amount of illumination the inside surface an imaginary 1foot radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere. Alternatively, it can be defined as the illuminance on a 1square foot surface of which there is a uniformly distributed flux of one lumen. This can be thought of as the amount of light that actually falls on a given surface. The footcandle is equal to one lumen per square foot. The SI derived unit of illuminance is the lux. One footcandle is equal to 10.76 lux, although in the lighting industry, typically this is approximated as 1 footcandle being equal to 10 lux. Footcandle is candles per foot. Illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelengthweighted by the luminosity function to correlate with human brightness perception. Illuminance is also known as Brightness. Zero Order Analysis permits evaluation of the total radiation that is absorbed into the cavity, that which is transmitted out, and the brightness of the surfaces. Zero Order Analysis is based on analysis of the diffuse radiation balance in a cavity. The higher the order of analysis the more detailed the results become. In Zero Order Analysis, a room is "unfolded" into a single concave surface for analysis assuming all surfaces will achieve the same diffuse "brightness". Radiant sources may be solar light transmitted through a window, or from an artificial light source in either case the surface area of the source must be considered.
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Average Transmittance (ta) is similar to the Transmittance value utilized in building envelope analysis, however averaged across all the interior surface areas taking into consideration the differing materials and areas of those materials to achieve an average value of transmittance of the concave surface. Average Transmittance is the percentage of the light striking the surface that is transmitted through the surface, therefore it has no units.  ta = (t·A)/A (A = Area) Average Reflectance (ra) is similar to the Reflectance value utilized in building envelope analysis, however averaged across all the interior surface areas taking into consideration the differing materials and areas of those materials to achieve an average value of reflectance of the concave surface. Average Reflectance is the percentage of the light striking the surface that is reflected by the surface, therefore it has no units.  ra = (r·A)/A (A = Area) Average Absorptance (ra) is similar to the Absorptance value utilized in building envelope analysis, however averaged across all the interior surface areas taking into consideration the differing materials and areas of those materials to achieve an average value of absorptance of the concave surface. Average Absorptance is the percentage of the light striking a surface that is absorbed by the surface, therefore it has no units.  aa = (a·A)/A (A = Area) Cavity Absorptance (ac) is the ability for the cavity to absorb the light energy emitted into it, taking into consideration the average reflectance value of the concave cavity surface after all the energy has either been absorbed into or transmitted out of the cavity. There is no Cavity Reflectance since ultimately all the energy in the cavity has to be either absorbed or transmitted out. Cavity Absorptance is the percentage of the light in the cavity that is absorbed by the cavity, therefore it has no units.  ac = aa/(1ra) Cavity Transmittance (tc) is the ability for the cavity to transmit out the light energy emitted into it, taking into consideration the average reflectance value of the concave cavity surface after all the energy has either been absorbed into or transmitted out of the cavity. There is no Cavity Reflectance since ultimately all the energy in the cavity has to be either absorbed or transmitted out. Cavity Transmittance is the percentage of the light in the cavity that is transmitted out of the cavity, therefore it has no units.  tc = ta/(1ra) Radiation Absorbed By Cavity (Ac) is the actual amount of light energy absorbed by the cavity, measured in BTU/hr. Area is already considered in the calculation of the Cavity Absorptance via Average Absorptance.  Ac = ac·Si Radiation Lost (Transmitted) By Cavity (Tc) is the actual amount of light energy transmitted out of the cavity, measured in BTU/hr. Area is already considered in the calculation of the Cavity Transmittance via Average Transmittance.  Tc = tc·Si Average Radiation Source (sa) is the equivalent energy source assuming all of the interior surfaces are radiating (glowing) to equal the actual radiation source. This assumption defines the Luminous Flux of the surfaces, measured in BTU/hr·sf.  sa = Si/A Average Cavity Brightness (ba) is the illumination level on the surface resulting from the Average Radiation Source which assumes all the surfaces (or single concave surface) is equally illuminated. It is a measure of the intensity of the light incident on a surface, measured in BTU/hrsf.  ba = sa/(1ra) Average Illuminance (Ia) converts the Average Brightness to the common units of illuminance (footcandles) utilizing the light source efficacy.  Ia = ba · (3.15 Watts/m2)/(1 BTU/hr·sf) · e · (1 footcandle)/(10 lumens/m2)
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Calculate Zero Order Analysis of cavity. Given: twall = 0 rwall = 0.60 tglass = 0.70 rglass = 0.05 tfloor = 0 rfloor = 0.50 tceiling = 0 rceiling = 0.70 Seast = 155.00 BTU/hr·sf Swest = 155.00 BTU/hr·sf Zero Order Analysis: Area t (sf) South 300 0 East 150 0 East Glass 50 0.70 North 300 0 West 150 0 West Glass 50 0.70 Floor 600 0 Ceiling 600 0 Totals 2,200
awall = 0.40 aglass = 0.25 afloor = 0.50 aceiling = 0.30
t·A (sf) 0 0 35.00 0 0 35.00 0 0 70.00
r 0.60 0.60 0.05 0.60 0.60 0.05 0.50 0.70
r·A (sf) 180.00 90.00 2.50 180.00 90.00 2.50 300.00 420.00 1,265.00
a 0.40 0.40 0.25 0.40 0.40 0.25 0.50 0.30
a·A (sf) 120.00 60.00 12.50 120.00 60.00 12.50 300.00 180.00 865.00
S (BTU/hr·sf) 0 0 155.00 0 0 155.00 0 0 Si =
S·A (BTU/hr) 0 0 7,750.00 0 0 7,750.00 0 0 15,500.00
Average Transmittance: ta = (t·A)/A = 70.00/2,200 = 0.03 Average Reflectance: ra = (r·A)/A = 1,265.00/2,200 = 0.58 Average Absorptance: aa = (a·A)/A = 865.00/2,200 = 0.39 Cavity Absorptance: ac = aa/(1ra) = 0.39/(10.58) = 0.93 Cavity Transmittance: tc = ta/(1ra) = 0.03/(10.58) = 0.07 Radiation Absorbed By Cavity: Ac = ac·Si = 0.93·15,500 BTU/hr = 14,415 BTU/hr Radiation Lost (Transmitted) By Cavity: Tc = tc·Si = 0.07·15,500 BTU/hr= 1,085.00 BTU/hr Average Radiation Source: sa = Si/A = 15,500 BTU/hr / 2,200=7.05 BTU/hr·sf Average Cavity Brightness: ba = sa/(1ra) = 7.05 BTU/hr·sf/(10.58)=16.79 BTU/hr·sf Average Illuminance of cavity in footcandles assuming daylight source (glazing):  Efficacy of sunlight = e = 114 lumens/Watt Ia = ba · (3.15 Watts/m2)/(1 BTU/hr·sf) · e · (1 footcandle)/(10 lumens/m2) = 16.79 BTU/hr·sf · (3.15 Watts/m2)/(1 BTU/hr·sf) · 114 lm/Watt · (1 fc)/(10 lm/m2) = 602.95 footcandles Average Illuminance of cavity in footcandles assuming fluorescent source (artificial):  Efficacy of fluorescent = e = 65 lumens/Watt Ia = ba · (3.15 Watts/m2)/(1 BTU/hr·sf) · e · (1 footcandle)/(10 lumens/m2) = 16.79 BTU/hr·sf · (3.15 Watts/m2)/(1 BTU/hr·sf) · 65 lm/Watt · (1 fc)/(10 lm/m2) = 343.79 footcandles VIII. Daylighting, First Order Analysis First Order Analysis examines the interior of a space similar to the Zero Order Analysis, however assumes the interior surfaces as two surfaces one which the analysis is concerned with ("reference surface"), and the other surfaces are combined into a single second surface (surfaces 1 and 2, respectively). This method derives more accurate data for the surface of interest; overall results for radiation absorbed and transmitted are equal to Zero Order Analysis (Conservation of Energy).  Average Transmittance (tan) is similar to the Average Transmittance value utilized in Zero Order Analysis, however the averages are divided among the two surfaces. Average Transmittance is the percentage of the light striking the surface that is transmitted through the surface, therefore it has no units (n = surface number).  ta1 = (t1·A1)/A1 ta2 = (t2·A2)/A2 (A = Area)
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Average Reflectance (ran) is similar to the Average Reflectance value utilized in Zero Order Analysis, however the averages are divided among the two surfaces. Average Reflectance is the percentage of the light striking the surface that is reflected by the surface, therefore it has no units (n = surface number).  ra1 = (r1·A1)/A1 ra2 = (r2·A2)/A2 (A = Area) Average Absorptance (ran) is similar to the Average Absorptance value utilized in Zero Order Analysis, however the averages are divided among the two surfaces. Average Absorptance is the percentage of the light striking a surface that is absorbed by the surface, therefore it has no units (n = surface number).  aa1 = (a1·A1)/A1 aa2 = (a2·A2)/A2 (A = Area) Area Ratio Factor (f) is the ratio of the two cavity surfaces, it therefore has no units.  f = A1/A2 Reflectance Quotient () is tool do "divide" the Average Reflectances to the cavity surfaces; it therefore has no units.  = 1 ra2·[1(1ra1)·f] Radiation Received By Each Surface (Rn) is the amount of light energy striking each of the two cavity surfaces, measured in BTU/hr (area is considered in the Average Reflectance). This calculation utilizes the Area Ratio Factor (f) and the Reflectance Quotient ().  R1 = (ra2·f·Si1 + f·Si2)/  R2 = {Si1+[1f·(1ra1)]·Si2}/ Radiation Absorbed By Each Surface (Acn) is the amount of light energy absorbed by the two cavity surfaces, measured in BTU/hr. Area is already considered in the calculation of the Radiation Received By Each Surface and Average Reflectance (n = surface number).  Ac1 = aa1·R1  Ac2 = aa2·R2 Total Radiation Absorbed By Cavity (Act) is equivalent to the Radiation Absorbed By Cavity in the Zero Order Analysis, measured in BTU/hr.  Act = Ac1 + Ac2 Cavity Absorptance (ac) is the ability for the cavity to absorb the light energy emitted into it, taking into consideration the average reflectance values of the cavity surfaces after all the energy has either been absorbed into or transmitted out of the cavity. For the First Order Analysis, the Total Radiation Absorbed By Cavity must be first calculated to achieve the Cavity Absorptance. There is no Cavity Reflectance since ultimately all the energy in the cavity has to be either absorbed or transmitted out. Cavity Absorptance is the percentage of the light in the cavity that is absorbed by the cavity, therefore it has no units.  ac = Act / (Si1 + Si2) Radiation Lost (Transmitted) By Each Surface (Tcn) is the amount of light energy transmitted out by the two cavity surfaces, measured in BTU/hr. Area is already considered in the calculation of the Radiation Received By Each Surface and Average Transmittance (n = surface number).  Tc1 = ta1·R1  Tc2 = ta2·R2 Total Radiation Lost (Transmitted) By Cavity (Tct) is equivalent to the Radiation Lost (Transmitted) By Cavity in the Zero Order Analysis, measured in BTU/hr.  Tct = Tc1 + Tc2 Cavity Transmittance (tc) is the ability for the cavity to transmit out the light energy emitted into it, taking into consideration the average reflectance values of the cavity surfaces after all the energy has either been absorbed into or transmitted out of the cavity. For the First Order Analysis, the Radiation Lost (Transmitted) By Cavity must first be calculated. There is no Cavity Reflectance since ultimately all the energy in the cavity has to be either absorbed or transmitted out. Cavity Transmittance is the percentage of the light in the cavity that is transmitted out of the cavity, therefore it has no units.  tc = Tct / (Si1 + Si2) Brightness Of Each Surface (ba) is the illumination level on the cavity surfaces. The concept of an Average Radiation Source is not applicable with two different surfaces defined
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the calculation is much more complex. It is a measure of the intensity of the light incident on a surfaces, measured in BTU/hr·sf.  b1 = {[1ra2·(1f)]·Si1+(ra1·f·Si2)}/(A1·)  b2 = [(ra2·Si1)+Si2)]/(A2·) Illuminance Of Each Surface (In) converts the Brightness Of Each Surface to the common units of illuminance (footcandles) utilizing the light source efficacy (n = surface number).  I1 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R1/A1 · (1 footcandle)/(10 lumens/m2)  I2 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R2/A2 · (1 footcandle)/(10 lumens/m2)
Calculate First Order Analysis of cavity with the floor as reference surface. Given: twall = 0 rwall = 0.60 awall = 0.40 tglass = 0.70 rglass = 0.05 aglass = 0.25 tfloor = 0 rfloor = 0.50 afloor = 0.50 tceiling = 0 rceiling = 0.70 aceiling = 0.30 Seast = 155.00 BTU/hr·sf Swest = 155.00 BTU/hr·sf
First Order Analysis Surface 1: Area1 t1·A1 t1 r1 (sf) (sf) Floor 600 0 0 0.50 Totals 600 0 First Order Analysis Surface 2: Area2 t2·A2 t2 (sf) (sf) South 300 0 0 East 150 0 0 East Glass 50 0.70 35.00 North 300 0 0 West 150 0 0 West Glass 50 0.70 35.00 Ceiling 600 0 0 Totals 1,600 70.00 Average Transmittance: Average Reflectance: Average Absorptance: Area Ratio Factor: Reflectance Quotient:
r1·A1 (sf) 300.00 300.00
a1 0.50
a1·A1 (sf) 300.00 300.00
S1 (BTU/hr·sf) 0 Si1 =
S1·A1 (BTU/hr) 0 0
r2 0.60 0.60 0.05 0.60 0.60 0.05 0.70
r2·A2 (sf) 180.00 90.00 2.50 180.00 90.00 2.50 420.00 965.00
a2 0.40 0.40 0.25 0.40 0.40 0.25 0.30
a2·A2 (sf) 120.00 60.00 12.50 120.00 60.00 12.50 180.00 565.00
S2 (BTU/hr·sf) 0 0 155.00 0 0 155.00 0 Si2 =
S2·A2 (BTU/hr) 0 0 7,750.00 0 0 7,750.00 0 15,500.00
ta1 = (t1·A1)/A1 = 0 ta2 = (t2·A2)/A2 = 0.04 ra1 = (r1·A1)/A1 = 0.50 ra2 = (r2·A2)/A2 = 0.60 aa1 = (a1·A1)/A1 = 0.50 aa2 = (a2·A2)/A2 = 0.35 f = A1/A2 = 600 sf / 1,600 sf = 0.38 = 1 ra2·[1(1ra1)·f] = 1 0.60·[1(10.50)·0.38] = 0.51
Radiation Received By Each Surface: R1 = (ra2·f·Si1 + f·Si2)/ = (0.60·0.38·0 + 0.38·15,500.00 BTU/hr)/0.51 = 11,549.02 BTU/hr R2 = {Si1+[1f·(1ra1)]·Si2}/ = {0+[10.38·(10.50)]·15,500.00 BTU/hr}/0.51 = 24,617.65 BTU/hr Radiation Absorbed By Each Surface: Ac1 = aa1·R1 = 0.50 · 11,549.02 BTU/hr = 5,774.51 BTU/hr Ac2 = aa2·R2 = 0.35 · 24,617.65 BTU/hr = 8,616.18 BTU/hr Total Radiation Absorbed By Cavity: Act = Ac1 + Ac2 = 5,774.51 BTU/hr + 8,616.18 BTU/hr = 14,390.69 BTU/hr * * equals value from Zero Order Analysis (14,415 BTU/hr)
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Cavity Absorptance: ac = Act / (Si1 + Si2) = 14,390.69 BTU/hr / (0 + 15,500.00 BTU/hr) = 0.93 * * equals value from Zero Order Analysis (0.93) Radiation Lost (Transmitted) By Each Surface: Tc1 = ta1·R1 = 0 · 11,549.02 BTU/hr = 0 BTU/hr Tc2 = ta2·R2 = 0.04 · 24,617.65 BTU/hr = 984.71 BTU/hr Total Radiation Lost (Transmitted) By Cavity: Tct = Tc1 + Tc2 = 0 BTU/hr + 984.71 BTU/hr = 984.71 BTU/hr * * equals value from Zero Order Analysis (1,085.00 BTU/hr) Cavity Transmittance: tc = Tct / (Si1 + Si2) = 984.71 BTU/hr / (0 + 15,500.00 BTU/hr) = 0.06 * * equals value from Zero Order Analysis (0.07) Brightness Of Each Surface: b1 = {[1ra2·(1f)]·Si1+(ra1·f·Si2)}/(A1·) = {[10.60·(10.38)]·0+(0.50·0.38·15,500.00BTU/hr)}/(600sf·0.51) = 9.62 BTU/hr·sf b2 = [(ra2·Si1)+Si2)]/(A2·) = [(0.60·0)+ 15,500.00 BTU/hr)]/(1,600 sf·0.51) = 19.00 BTU/hr·sf Illuminance Of Each Surface of cavity in footcandles assuming daylight source (glazing):  Efficacy of sunlight = e = 114 lumens/Watt I1 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R1/A1 · (1 footcandle)/(10 lumens/m2) = (114 lm/Watt)·(3.15 Watts/m2)/(1 BTU/hr·sf)·(11,549.02 BTU/hr)/(600 sf)·(1 fc)/(10 lm/m2) = 692.94 footcandles I2 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R2/A2 · (1 footcandle)/(10 lumens/m2) = (114 lm/Watt)·(3.15 Watts/m2)/(1 BTU/hr·sf)·( 24,617.65 BTU/hr)/(1,600 sf)·(1 fc)/(10 lm/m2) = 553.90 footcandles Illuminance Of Each Surface of cavity in footcandles assuming fluorescent source (artificial):  Efficacy of sunlight = e = 65 lumens/Watt I1 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R1/A1 · (1 footcandle)/(10 lumens/m2) = (65 lm/Watt)·(3.15 Watts/m2)/(1 BTU/hr·sf)·(11,549.02 BTU/hr)/(600 sf)·(1 fc)/(10 lm/m2) = 394.11 footcandles I2 = e · (3.15 Watts/m2)/(1 BTU/hr·sf) · R2/A2 · (1 footcandle)/(10 lumens/m2) = (65 lm/Watt)·(3.15 Watts/m2)/(1 BTU/hr·sf)·(24,617.65 BTU/hr)/(1,600 sf)·(1 fc)/(10 lm/m2) = 315.03 footcandles IX. Solar Admittance and UAValue Incident Radiation (I) is the radiation energy striking a surface.  I=A+R+T  A is the absorbed component  R is the reflected component  T is the transmitted component Absorptivity is the quality of a material that affects the amount of Incident Radiation that will be absorbed by the material. Absorptance (a) is the percentage of energy absorbed, measured normal (perpendicular) to the surface.  a = A/I a+r+t=1
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Reflectivity is the surface quality of a material that affects the amount of Incident Radiation that will be reflected by the surface.  Color, texture, shape, and angle of incidence effects surface Reflectivity. Reflectance (r) is the percentage of energy reflected, measured normal (perpendicular) to the surface.  r = R/I a+r+t=1 Transmisivity is the quality of a material that affects the amount of Incident Radiation that will be transmitted through the material. Transmittance (t) is the percentage of energy transmitted, measured normal (perpendicular) to the surface.  t = T/I a+r+t=1 Opaque materials do not transmit radiant energy. Translucent materials transmit radiant energy.  Transparent materials are a subset of translucent materials. Calculate Insolation on vertical surface based on Direct Solar Normal and Zenith. Given: Direct Solar Normal = 300 BTU/hr·sf Zenith = 30° Solve: Altitude is 60° (compliment of Zenith) 30 60 90 triangle has leg lengths equal to 1 3 2 Horizontal component is ½ of hypotenuse S = 150 BTU/hr·sf
Calculate absorbed, reflected, and transmitted components. Given: a = 0.3 r = 0.5 t = 0.2 Solve: Absorbed component = a·S = 0.3 · 150 BTU/hr·sf = 45 BTU/hr·sf Reflected component = r·S = 0.5 · 150 BTU/hr·sf = 75 BTU/hr·sf Transmitted component = t·S = 0.2 · 150 BTU/hr·sf = 30 BTU/hr·sf
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Solar Admittance (as) is similar in concept to conductive heat gain, but instead calculates in percentage the effect of direct solar gain through the building envelope, ignoring exterior and interior air temperature since these to not effect the strength or angle of incidence of the Sun's rays. Solar Admittance is divided into two components: conductive and transmissive.  Note: Solar Absorptance = aS is not Solar Admittance = as  as = a·(U/Co) = a·(U/ho) a = Absorptance of exterior surface material U = airtoair Conductance of assembly (includes air film coefficients) Co (or ho) = outside air film conductive coefficient  as = t·ac t = Transmittance of material ac = Room Cavity Absorptance  as = [a·(U/Co)]+(t·ac) Total Solar Admittance Calculate Conductive Solar Admittance of an Opaque wall assembly (conductive effect with no transmission). Given: a = 0.6 U = 0.50 BTU/hr·sf·°F (airtoair value including air film coefficients) Co = 4.00 BTU/hr·sf·°F (7.5 Miles Per Hour breeze) Solve: as = a·(U/Co) as = 0.6 · (0.50 BTU/hr·sf·°F / 4.00 BTU/hr·sf·°F) = 0.075 = 7.5% The Solar Admittance is 7.5%, meaning 7.5% of the solar energy striking the exterior surface of the wall assembly will be "admitted" into the cavity. Conductive Solar Gain (hs) is the heat gain flux by a cavity due to conductive Solar Admittance.  hs = as ·S as = Solar Admittance S = Insolation Calculate Conductive Solar Gain flux of an Opaque wall assembly. Given: as = 0.075 = 7.5% S = 300 BTU/hr·sf Solve: hs = as ·S hs = 0.075 · 300 BTU/hr·sf = 22.5 BTU/hr·sf The wall assembly will admit 22.5 BTU/hr·sf of solar heat gain to the cavity. Room Cavity Absorptance (ac) is the percentage of the amount of transmissive energy admitted into a cavity that will be absorbed by the space (see sections VII and VIII). Albedo is the amount of energy reflected back out of the cavity through the transmissive material. Calculate Transmissive Solar Admittance of a translucent wall assembly (transmissive effect with no conduction). Given: t = 0.85 ac = 0.90 Solve: as = t·ac as = 0.85 · 0.90 = 0.77 = 77% The Solar Admittance is 77%, meaning 77% of the solar energy striking the exterior surface of the wall assembly will be "admitted" into the cavity. Transmissive Solar Gain (hs) is the heat gain flux by a cavity due to transmissive Solar Admittance.  hs = as ·S as = Solar Admittance S = Insolation
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Calculate Transmissive Solar Gain flux of an Translucent wall assembly. Given: as = 0.77 = 77% S = 300 BTU/hr·sf Solve: hs = as ·S hs = 0.77 · 300 BTU/hr·sf = 231 BTU/hr·sf The wall assembly will admit 232 BTU/hr·sf of solar heat gain to the cavity. Total Solar Gain (hs) is the heat gain flux by a cavity due to conductive and transmissive Solar Admittance.  hs = ([(a·(U/Co)]+(t·ac))·S  hs = ([(a·(U/Co)]·S)+[(t·ac)·S] Calculate Total Solar Admittance Solar Gain flux of an combined wall assembly. Given: a = 0.2 t = 0.6 r = 0.2 ac = 0.85 U = 0.50 BTU/hr·sf·°F (airtoair value including air film coefficients) Co = 4.00 BTU/hr·sf·°F (7.5 Miles Per Hour breeze) S = 300 BTU/hr·sf Solve:  hs = ([(a·(U/Co)]+(t·ac))·S hs = ([(0.2·(0.50 BTU/hr·sf·°F/4.00 BTU/hr·sf·°F)]+(0.6·0.85))·300 BTU/hr·sf hs = 160.50 BTU/hr·sf UAValue is a weighted UValue taking into effect the relative building wall areas of differing assemblies within a building envelope. UAValue is used to calculate the interior "floating" temperature to calculate the mechanical need to obtain thermal comfort, and assumes an unoccupied cavity with no equipment (BTU/hr·°F).  UAValue = U·A = UValue·Area  Heat Balance Equation: Q+ M + H = 0 M=0 [U·A·(ToTi)]+H = 0 Ti = To+[H/(U·A)]  Note: values are rates since multiplying UValue times Area cancels the area in the denominator, leaving BTU/hr·°F, the °F cancels by multiplying by deltaT. Calculate interior floating temperature of a building envelope. Given: To = 54°F UA = 20,000 BTU/hr·°F H = 300,000 BTU/hr Solve: Ti = To+[H/(U·A)] Ti = 54°F+[(300,000 BTU/hr)/(20,000 BTU/hr·°F)] = 69°F Calculate mechanical input to increase interior temperature to 72°F. Given: Tc = 72°F Ti = 69°F UA = 20,000 BTU/hr·°F Solve: M = U·A· (TcTi) M = (20,000 BTU/hr·°F)·(72°F69°F) = 60,000 BTU/hr
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Calculate UAValue for a building envelope, assuming steady state conditions. Given: A rectangular solid building 40 feet long, 20 feet wide, 20 feet high Window (glass) in Southfacing wall 120 square feet Uopaque = 0.05 BTU/hr·sf·°F Uglass = 0.25 BTU/hr·sf·°F UAinfiltration = 192 BTU/hr·°F tg = 0.85 transmittance of glass ag = 0.10 absorptance of glass aw = 0.50 absorptance of wall ac = 0.90 cavity absorptance To = 54°F outdoor temperature Ss = 142.17 BTU/hr·sf Insolation South Se = 95.00 BTU/hr·sf Insolation East Sw = 13.33 BTU/hr·sf Insolation West Sn = 13.17 BTU/hr·sf Insolation North Sz = 85.33 BTU/hr·sf Insolation Zenith Solve for UAValue: Area UValue UAValue (square feet) (BTU/hr·sf·°F) (BTU/hr·°F) Infiltration 192.00 South Glass 120 0.25 30.00 South Opaque 680 0.05 34.00 East Opaque 400 0.05 20.00 West Opaque 400 0.05 20.00 North Opaque 800 0.05 40.00 Zenith Opaque 800 0.05 40.00 Floor Opaque 800 0.05 40.00 416.00 * * UAValues ARE additive. UAValue = 416.00 BTU/hr·°F Calculate Solar Heat Gain Rate for a building envelope, assuming steady state conditions. Given: A rectangular solid building 40 feet long, 20 feet wide, 20 feet high Window (glass) in Southfacing wall 120 square feet Uopaque = 0.05 BTU/hr·sf·°F Uglass = 0.25 BTU/hr·sf·°F UAinfiltration = 192 BTU/hr·°F tg = 0.85 transmittance of glass ag = 0.10 absorptance of glass aw = 0.50 absorptance of wall ac = 0.90 cavity absorptance To = 54°F outdoor temperature Ss = 142.17 BTU/hr·sf Insolation South Se = 95.00 BTU/hr·sf Insolation East Sw = 13.33 BTU/hr·sf Insolation West Sn = 13.17 BTU/hr·sf Insolation North Sz = 85.33 BTU/hr·sf Insolation Zenith
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South Glass South Opaque East Opaque West Opaque North Opaque Zenith Opaque
Solar Admittance * as = [a·(U/Co)]+(t·ac) 0.80 0.006 0.006 0.006 0.006 0.006
Area (square feet) 120 680 400 400 800 800
Insolation (BTU/hr·sf) 142.17 142.17 95.00 13.33 13.17 85.33
Heat Gain (BTU/hr) 13,648.32 580.05 228.00 31.99 63.22 409.58 14,961.16
* There is NO Solar Admittance due to Infiltration or from the floor Solar Heat Gain Rate = Hs = 14,961.16 BTU/hr Calculate interior floating temperature of a building envelope. Given: To = 54°F outdoor temperature Hs = 14,961.16 BTU/hr Solar Heat Gain Rate UA = 416.00 BTU/hr·°F UAValue Solve: Ti = To+[H/(U·A)] Ti = 54°F+[14,961.16 BTU/hr/(416.00 BTU/hr·°F)] = 89.96°F The interior temperature has the potential to be almost 90°F in a steady state condition. The reality is that thermal inertia (lag time) will cause the actual interior temperature to lag behind this steady state temperature. For example, if the steady state temperature for the hour proceeding this hour was 84°F, the average temperature this hour is probably somewhere between the two. X. Thermal Comfort and Mechanical Loads Calculate Building Envelope Design for Thermal Comfort (78°F) by sizing a window. Substitute the variable "g" for the area of glazing and solve as before. Given: A rectangular solid building 40 feet long, 20 feet wide, 20 feet high Window (glass) in Southfacing wall unknown size (area = "g") Uopaque = 0.05 BTU/hr·sf·°F Uglass = 0.25 BTU/hr·sf·°F UAinfiltration = 192 BTU/hr·°F tg = 0.85 transmittance of glass ag = 0.10 absorptance of glass aw = 0.50 absorptance of wall ac = 0.90 cavity absorptance To = 54°F outdoor temperature Ss = 142.17 BTU/hr·sf Insolation South Se = 95.00 BTU/hr·sf Insolation East Sw = 13.33 BTU/hr·sf Insolation West Sn = 13.17 BTU/hr·sf Insolation North Sz = 85.33 BTU/hr·sf Insolation Zenith Ti = 78°F
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Area (square feet) g 800g 400 400 800 800 800
UValue (BTU/hr·sf·°F) 0.25 0.05 0.05 0.05 0.05 0.05 0.05
UAValue (BTU/hr·°F) 192.00 0.25g 400.05g 20.00 20.00 40.00 40.00 40.00 392 + 0.20g *
* UAValues ARE additive. Solve for Heat Gain Rate: Solar Admittance * as = [a·(U/Co)]+(t·ac) 0.80 0.006 0.006 0.006 0.006 0.006 Area (square feet) g 800g 400 400 800 800 Insolation (BTU/hr·sf) 142.17 142.17 95.00 13.33 13.17 85.33 Heat Gain (BTU/hr) 114.16g 684.960.86g 228.00 31.99 63.22 409.58 1.354.53+113.30g
South Glass South Opaque East Opaque West Opaque North Opaque Zenith Opaque
* There is NO Solar Admittance due to Infiltration or from the floor Solve for Glass Area: Ti = To+[H/(U·A)] 78°F = 54°F +[((1.354.53+113.30g) BTU/hr)/((392 + 0.20g) BTU/hr·°F)] 24°F = ((1.354.53+113.30g) BTU/hr)/((392 + 0.20g) BTU/hr·°F) (1.354.53+113.30g) BTU/hr = 24°F·((392 + 0.20g) BTU/hr·°F) (1.354.53+113.30g) BTU/hr = 24°F·(392 BTU/hr·°F) + 24°F·((0.20g) BTU/hr·°F) (113.30g) BTU/hr 4.80g BTU/hr = 9,408.00 BTU/hr  1.354.53 BTU/hr 128.50g BTU/hr = 8,053.47 BTU/hr g = 62.67 square feet (square feet are known as the units with "g" defined as area) Mechanical Demand is the mechanical input to add or remove heat from a space (cavity) to provide thermal comfort. The Mechanical Load can be determined by calculation, but the sizing of equipment to provide the necessary heat energy addition or extraction is based on such a calculation plus: equipment efficiencies, delivery system efficiency, and humidity control. Calculate Mechanical Demand for Thermal Comfort (78°F) by applying heat extraction (ignoring efficiency and humidity control). Given: Ti = 89.96°F (Temperature of the interior = initial temperature) Tc = 78°F (Temperature for cooling = target temperature) UAValue = 416.00 BTU/hr·°F Solve for Mechanical Demand: M = U·A·(TcTi) M = 416.00 BTU/hr·°F (89.96°F  78°F) M = 4,965.36 BTU/hr (negative means cooling) To maintain an interior temperature of 78°F, 4,965.36 BTU of energy must be extracted every hour assuming steady state conditions. However, the interior temperature will change every hour, as will the Mechanical Demand.
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Mechanical Demand Costs are the real financial impacts of requiring Mechanical Demands to maintain thermal comfort. It is calculated based on Mechanical Demand and equipment efficiency. Watt (W) is an International System (SI) unit of power that equals 1 Joule per second (J/s). Joule (J) is an SI unit of energy that equals 9.48x104 BTU (1 Joule = 2.78x107 kWh). Therm is a unit of heat used for calculations of combustion (fuel) equivalent to 100,000 BTU. Ton is equivalent to 12,000 Btuh (BTU per hour) and is based on the cooling effects of one ton (2,000 pounds) of water ice. Cooling equipment is produced in sized with specifically defined tons of cooling. A typical house system will require 1.0 to 3.0 ton Equipment Capacity approximately 1 ton per 500 square feet of habitable area. Calculate Mechanical Demand Cost of one hour for above Mechanical Demand using electrical condenser/evaporator system (disregarding equipment efficiency and humidity control). Given: Time (t) = 1 hour M = 4,965.36 BTU/hr SDG&E 2004 Electric Energy Cost = $0.15/kWh (kWh = kilowatthour or kilowatt times hour) Convert BTU to kWh: 4,965.36 BTU/hr · 1 hour = 4,965.36 BTU 4,965.36 BTU · (1 J / 9.48x104 BTU) = 5,237,721.52 J 5,237,721.52 J · (2.78x107 kWh / 1 J) = 1.46 kWh (negative means cooling) For the hour defined, the energy removal requirement to provide thermal comfort (not including maintaining humidity levels) is 1.46 kWh. Solve for cost: 1.46 kWh · $0.15/kWh = $0.22 Assuming 100% equipment efficiency, the cost to remove the energy needed to achieve thermal comfort (not including maintaining humidity levels) is $0.22 per hour. Extrapolate assuming 6 hours a day of cooling for half a year: 365 days per year / 2 = 182.5 days 182.5 days · 6 hours = 1,095 hours for cooling 1095 hours · $0.22/hr = $240.90 per year for cooling This is of course just a rough estimate for showing order of magnitude. Proper calculations would be per hour per day incorporating humidity control and equipment and delivery systems efficiency to identify true costs. Seasonal Energy Efficiency Ratio (SEER) is the total cooling of a central air conditioner or total cooling/heating of a central heat pump in BTUs during its normal annual usage period for cooling divided by the total electric energy input watthours during the same period. This is a measure of unit efficiency. Federal Law identifies minimum SEER ratings of 13 the higher the SEER, the more efficient the equipment. The SEER calculation was developed by the U.S. Department of Energy (DOE) in an effort to simulate actual operation of systems in the field. The test is more complicated than Energy Efficiency Ratio (EER) and uses a number of operating conditions, including equipment cycling. Also included in calculation is the electricity used by the indoor blower motor, outdoor fan motor, and compressor when matched with a specific indoor coil. SEER is used for all ducted systems producing up to 65,000 Btu's of cooling. Annual Fuel Efficiency Ratio (AFUE) is the ratio of annual output energy to annual input energy which includes any nonheating season pilot input loss, and for gas or oil fired furnaces or boilers does not include electric energy. The ratio is based on 5,200 annual average heating hours and 4,600 average nonheating hours per year for pilot use. Federal Law identified the national minimum as 78%. Annual Electric Equipment Operations Costs is determined based on calculating the highest mechanical demand, sizing the equipment to the next highest available capacity, determining the average number of cooling/heating hours per year, and the cost rate for electricity acquisition.  Annual Cost = Capacity (Btuh)/SEER · Cooling Load Hours/1000 · Electricity Cost Rate Annual Fuelfired Equipment Operations Costs is determined based on calculating the highest mechanical demand, sizing the equipment to the next highest available capacity, determining the
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average number of heating hours per year, fuel heating value based on fuel used, and the cost rate for fuel acquisition.  Annual Cost = Capacity (Btuh)/AFUE · Heating Load Hours/Fuel Heating Value · Fuel Cost Rate Calculate Annual Equipment Operations Cost applying the minimum SEER rating of 13 to the example above with the Estimated Equivalent Rated Full Load Hours Of Operation For Properly Sized Equipment During Normal Cooling Season for San Diego of 8001,700 hours. Given: Mechanical Demand as calculated = 4,965.36 BTU/hr = 0.41 tons Building Floor Area = 40 feet by 20 feet, 20 feet high = 1,600 square feet (2 stories) Equipment Capacity required ~ 3.0 tons = 3.0 x 12,000 Btuh = 36,000 Btuh Expect higher peak demand based on building area = 36,000 Btuh * Hours of operation = 1,700 hours (design for maximum comfort) SDG&E 2004 Electric Energy Cost = $0.15/kWh (kWh = kilowatthour or kilowatt times hour) Solve: Annual Cost = Capacity (Btuh)/SEER · Cooling Load Hours/1000 · Electricity Cost Rate Annual Cost = 36,000 Btuh / 13.00 · 1,700 hrs /1000 · $0.15/kWh Annual Cost = 2,769.23 · 1.7 · $0.15 = $706.15 It will cost approximately $706.15 to cool this structure annually as originally designed. Adjust SEER to EnergyStar compliant 19 and solve: Annual Cost = Capacity (Btuh)/SEER · Cooling Load Hours/1000 · Electricity Cost Rate Annual Cost = 36,000 Btuh / 19.00 · 1,700 hrs /1000 · $0.15/kWh Annual Cost = 1894.74 · 1.7 · $0.15 = $483.16 It will cost approximately $483.16 to cool this structure annually as originally designed. * The date selected for original steadystate floating analysis is not the extreme Winter case to be designed for. Most residentiallysized cooling equipment does not have variable temperature, volume, or speed control; therefore the equipment operates at full capacity while in operation and equipment must be sized to handle the extreme situation to assure thermal comfort (unless lessthanoptimum comfort is acceptable by program). The Estimated Equivalent Rated Full Load Hours Of Operation For Properly Sized Equipment During Normal Cooling Season takes this into consideration in determining the number of hours used in calculations. XI. Electric Lighting Electric Lighting Demand is the artificial lighting needed to provide the desired or required illuminance on a surface or in a space. Electric light is used to both supplement daylight and to provide lighting in dark hours of the day (night, cloudy conditions, etc.). Lighting design should provide for both all a space's needed or required lighting and supplemental lighting for various daylight conditions and degrees. Fixture ("Luminaire") is a device that houses an artificial light source and usually has components used to direct (lens), spread (reflector), contain (housing), or otherwise "fix" the emanating light. Lamp is the light source within a fixture, commonly referred to as a "bulb". Lamps can be arraigned into two major categories: incandescent and fluorescent, each with subcategories. Radiant Flux is the amount of total radiation of all wavelengths emitted by a light source. Luminous Flux is the amount of visible radiation (i.e. "light") emitted by a light source. Power is energy use per time period, commonly measured as a Watt (Joule per second); it is NOT a measure of light output. We are accustomed to thinking of lamps (light bulbs) in terms of power in Watts but what this tells you is how quickly the lamp will consume electricity, not how effective it will be in lighting. Because incandescent lamps sold for "general service" all have fairly similar characteristics, power has become a guide to light output, but only a rough one. Efficiency is the ratio of energy output per energy input. An incandescent lamp (light bulb) is about 80% efficient. The Radiant Flux of a 60 Watt incandescent lamp is approximately 48 Watts. The Luminous Flux of a 60 Watt incandescent lamp is approximately 850 lumens, resulting in an efficacy of approximately 14 lumens/Watt. Luminous Efficiency is the ratio of the luminous Efficacy to the maximum possible value of 683 lumens/Watt, or approximately 2% for a 60 Watt incandescent lamp.
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Therefore, if 2% of the energy input is converted to visible light, and 80% of the energy input is converted to radiation (including light), 78% of the input energy is converted to wavelengths other than visible light mostly in the infrared (heat). Efficacy (e) is the ability to produce a desired amount of a desired effect. In lighting design, "efficacy" refers to the amount of visible illumination produced by a lamp (a light bulb or other light source), usually measured in lumens, as a ratio of the amount of energy consumed to produce the illumination, usually measured in Watts. This is not to be confused with efficiency which is always a dimensionless ratio of output divided by input, which for lighting relates to the Watts of visible energy as a ratio of the energy consumed in Watts (Watt/Watt). The maximum efficacy possible is 683 lumens/Watt with 100% of the energy input being converted to illuminance.  Efficacy of sunlight = e = 114 lumens/Watt = 36 footcandles per BTU/hr·sf  Efficacy of fluorescent = e = 65 lumens/Watt = 20 footcandles per BTU/hr·sf  Efficacy of incandescent = e = 14 lumens/Watt = 4 footcandles per BTU/hr·sf Lumen (lm) is the SI unit of luminous flux, a measure of the perceived power of light. Luminous flux differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light. If a light source emits one candela of luminous intensity into a solid angle of one steradian, the total luminous flux emitted into that solid angle is one lumen. Alternatively, an isotropic onecandela light source emits a total luminous flux of exactly 4 lumens. The lumen can be thought of casually as a measure of the total "amount" of visible light emitted. Lux (lx) is the SI unit of illuminance. It is used in photometry as a measure of the intensity of light, with wavelengths weighted according to the luminosity function, a standardized model of human brightness perception. Lux is a derived unit based on lumen, and lumen is a derived unit based on candela.  1 lx = 1 lm/m2  The difference between the lux and the lumen is that the lux takes into account the area over which the luminous flux is spread. 1000 lumens, concentrated into an area of one square meter, lights up that square meter with an illuminance of 1000 lux. The same 1000 lumens, spread out over ten square meters, produces a dimmer illuminance of only 100 lux. Footcandle (sometimes footcandle; abbreviated fc, lm/ft², or sometimes ftc) is a nonSI unit of illuminance or light intensity widely used in photography, film, television, and the lighting industry. The unit is defined as the amount of illumination the inside surface an imaginary 1foot radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere. Alternatively, it can be defined as the illuminance on a 1square foot surface of which there is a uniformly distributed flux of one lumen. This can be thought of as the amount of light that actually falls on a given surface. The footcandle is equal to one lumen per square foot. The SI derived unit of illuminance is the lux. One footcandle is equal to 10.76 lux, although in the lighting industry, typically this is approximated as 1 footcandle being equal to 10 lux. Footcandle is candles per foot. Incandescent Lamps are a source of artificial light that works by incandescence  is the release of thermal radiation from a body due to its temperature. An electrical current passes through a thin tungsten filament, heating it and causing its molecules to become excited, releasing thermally equilibrated photons. The enclosing glass bulb prevents the oxygen in air from reaching the hot filament, which otherwise would be destroyed rapidly by burning. Incandescent Lamps have a very low efficacy and efficiency and are therefore sometimes selected as a light source to be used as heat sources to remove some of the burden of heating a room from a thermostaticallycontrolled system, particularly at night and during cold periods of the year. One reason why incandescent lamps are unpopular in commercial spaces is that the heat output results in the need for more air conditioning in the summer. An incandescent 60 watt lamp has an average lumen output of 850 lumens, resulting in an efficacy of approximately 14 lumens/Watt. Fluorescent Lamps are a gasdischarge lamps that uses electricity to excite mercury vapor in argon or neon gas, resulting in a plasma that produces shortwave ultraviolet light. This light then causes a phosphor to fluoresce (molecular absorption of a photons triggers the emission of other photons with a longer wavelength), producing visible light. A 15 Watt compact fluorescent lamp has an average lumen output of 950 lumens, with a resulting efficacy of 65 lumens/Watt; approximately four times that of incandescent lamps.
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Photometry is the science of measurement of light, in terms of its perceived brightness to the human eye. The human eye is not equally sensitive to all wavelengths of light. Photometry attempts to account for this by weighting the measured power at each wavelength with a factor that represents how sensitive the eye is at that wavelength. Many different units of measure are used for photometric measurements. The adjective "bright" can refer to a lamp which delivers a high luminous flux (measured in lumens), or to a lamp which concentrates the luminous flux it has into a very narrow beam (candelas). Because of the ways in which light can propagate through threedimensional space, spread out, become concentrated, reflect off shiny or matte surfaces, and because light consists of many different wavelengths, the number of fundamentally different kinds of light measurement that can be made is large, and so are the numbers of quantities and units that represent them. Photometric Charts describe the lighting pattern of a particular light fixture and lamp combination.
A
B
C 
D


Chart `A': Curve C at 50 Watts describes a 6.1 footcandle illumination approximately evenly distributed 9 feet from the source for a width of approximately 20 feet centered on the fixture. Note that the curve is not exactly symmetrical about the central axis, suggesting the lamp placement in the fixture (relative to the lens and/or reflector) may not be perfectly centered. Chart `B': To provide the California Building Code required 1 footcandle pathway illumination for building egress using this fixture and a 10 Watt lamp combination, the fixtures should be placed no more than 8 feet on center (4 foot radius). Chart `C': To only illuminate a 2 foot radius surface area, this lamp type should be located 8 feet from the surface. Chart `D': Due to characteristics of this fixture, there are two screened spots at 1 foot and 2 feet from the source.
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Light Reflections are divided into two primary types, "specular" and "diffuse".  Specular Reflection is the perfect, mirrorlike reflection of light from a surface, in which light from a single incoming direction is reflected into a single outgoing direction. Typically, a specular reflector is used in a light fixture when the desired result is a spot of bright light.  Diffuse Reflection is the reflection of light from an uneven or granular surface such that an incident ray is seemingly reflected at a number of angles. Typically, a diffuse reflector or diffusing lens is used in a light fixture when the desired result is even illuminance. Estimating the Required Installation of Electric Lighting is achieved by first determining the required or desired lighting on the reference surface, then using techniques from the First Order Analysis calculate the effects of electric lighting.  First Order Analysis is required to provide these values for the specific cavity.  Radiation Received By The Reference Surface (R1) is determined by the required illuminance (I) measured in lumens per square meter, the surface area of the reference surface (A) measured in square meters, and the efficacy of the light source (e) measured in Watts.  R1 = I1·A1/e  Magnitude Of Radiant Source (Si2) of the collected second surface is determined by the required illuminance (I) measured in lux (converted from footcandles), the surface area of the reference surface (A), and the efficacy of the light source (e); measured in Watts. Derivation of Radiation Received By Each Surface for reference surface: R1 = (ra2·f·Si1 + f·Si2)/.  Si2 = (R1·  ra2·f·Si1)/f Calculate Required Electric Lighting for a reference surface using a diffusing fluorescent source and assuming no daylighting (night, window shades open  transmittance). Given: Required Illuminance = 30 footcandles A1 = 600 square feet e = 65 lumens/Watt Si1 = 0 ra2 = 0.60 f = 0.38 = 0.51 Solve for Radiation Received By The Reference Surface. R1 = I1·A1/e R1 = {[30 fc·(10 lux/1 fc)·(1 lumen/m2 / 1 lux)]·[600 sf·(m2/10.76 sf)]} / 65 lumens/Watt R1 = 257.36 Watts Solve for Magnitude of Radiant Source of the collected second surface. Si2 = (R1·  ra2·f·Si1)/f Si2 = [(257.36 Watts·0.51)  0.60·0.38·0)]/0.38 Si2 = 677.26 Watts  677.26 Watts of electric power needs to be provided in the form of fluorescent lighting to provide the required illuminance. Assuming standard T12 32 Watt fluorescent tube, 3 to a recessed fixture, 7 such fixtures would be required (677.26 Watts / 32 Watts per lamp / 3 lamps per fixture = 7 fixtures).  Total radiation absorbed by the cavity (Act = Ac1 + Ac2) can now be calculated to determine heat gain from artificial lighting via First Order Analysis, to be added to other internal heat gain sources for thermal comfort calculations.
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Arrange Required Electric Lighting Fixtures. Based on the photometrics of fixture selected, arrangement of fixtures may not just be as simple as spacing fixtures on center based on Watt calculations. Depending on the desired program and design goals, the following factors may influence the fixture layout:  If program includes an average desktop illumination to be supplemented with task lighting, having some areas slightly underilluminated is probably OK (e.g. professional office, factory).  If program area requires minimum illumination at all locations without light and or dark spots, and space is used for highly detailed work, fixture selection and layout will require minimal overlap of fixture beams and complete reference surface coverage (e.g. laboratory).  Program may desire points of interest or focus be established (for wayfinding, signage, dramatic effect, etc.), then average illumination may not be desirous and lighting design will become a highly skilled responsibility (e.g. residential, museum, library).
Example 1: Lighting calculation required 15 fixtures and photometrics suggest fixture spacing of 2 feet on center; however, shape of space does not lend itself to an oddnumber of fixtures. One choice would be to locate 14 fixtures symmetrical in the room, leaving areas outside the beam spread underilluminated (at the perimeter walls where lighting is less needed for accomplishing tasks and where reflectance off the walls actually provide greater concentration of light). Underillumination can be overcome with task lighting.
Example 2: If the program requires absolute minimum illumination levels, beams can be overlapped to provide full coverage. This does lead to "hotspots" at beam overlaps that could cause glare and eye fatigue. This solution also requires 27 fixtures where 15 are sufficient via calculation to provide the necessary illumination thus causing overconsumption of electricity.
Example 3: Changing to fixtures with different photometric characteristics may provide greater illumination uniformity at less operations costs. For example, replacing fluorescent trough fixtures for incandescent recessed lights could result in the significant energy savings while meeting the lighting program.
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E n v i r o n m e n t a l Semester Project
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Purpose Apply knowledge acquired in class towards "realworld" experiences; expand learning potential through active participation in design of building environmental systems; to demonstrate learned comprehension of presented course material for course evaluation. Process Design a simple oneroom building to test thermodynamically and for appropriate illumination characteristics; and to schematically incorporate appropriate active mechanical, lighting, electrical, plumbing, and fire protection systems. A) A cursory evaluation and concept design by each student will be required, detailed engineering analysis will not be. B) Each student is to create a unique building design and is to prepare their report independently. Working together to reinforce understanding of material is encouraged. The semester project report is to be bound and clearly presented in written and graphic form. Utilize written and graphic techniques as necessary to fully describe your project's physical and performance characteristics. Evaluation will be based on understanding of course material, accuracy, clarity, and quality of presentation. Calculations may be included in a project appendix if desired (please reference calculations in project report body). Do not limit yourselves to the required texts for this course utilize the recommended texts list and/or any other relevant material as you see necessary in completing your project (bibliography and end/footnotes are required for referenced materials and data). Part 1  building design, solar geometry, climate, thermal comfort, beginning thermodynamics 1) Design a rectangular oneroom and onestory building with a flat roof. The goal is not to design a perfectly performing passive building, but to learn the effects on occupancy of decisions made in design process. Document you design with plans, elevations, sections, and a 3D sketch. Consider the following influencing factors (provide all these "assumptions" as part of your project narrative): A) Building use: what is the program for the building? B) Building size: what is the appropriate size to meet the program? C) Building location: is it urban, suburban, rural? D) What is the climate of the building site and building orientation on that site? E) How is the building constructed; what is the building envelope? F) What are the exterior and interior surface areas of the building envelope? G) How many openings ("fenestration") and of what kind are appropriate? 2) Identify (or define) building envelope assemblies. A) Calculate assembly RValues and UValues (considering air film coefficients consider building material and climate data in your air film coefficient determination) for each unique wall, window, door, roof, and floor assembly. B) Determine surface reflectance, transmittance, absorptive properties (consider material properties and colors). 3) Analyze building site conditions. Consider only the Winter and Summer solstices. A) Identify Latitude, Longitude, Altitude. B) Identify hourly average climatic (outdoor environmental) conditions: drybulb temperature, wetbulb temperature, relative humidity, absolute humidity, prevailing winds, enthalpy (use psychrometric chart if necessary). C) Identify hourly insolation values (direct normal solar heat gain factor (flux)) for each building surface, including the roof. D) Determine the hourly Azimuthal (), Zenith (Z), and Altitude () angles using the solar protractor. 4) Determine thermal comfort targets for your building define occupancy times and drybulb temperatures (assume floating interior humidity is equivalent to exterior humidly levels).
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Part 2 daylighting, advanced thermodynamics, active systems, water, tertiary systems 1) Determine (research) the desired lighting levels for your building's occupancy. Correlate the occupancy to times of the day to determine the lighting needed for daytime and for nighttime. 2) Prepare a daylighting First Order Analysis for your project building. Consider only the Winter and Summer solstices at 5AM, 8AM, 12PM, 4PM, 8PM, and 11PM (or use six other more appropriate times when the building is set to be occupied for its intended use). Consider the sunlight incident upon and transmitted through the building's windows as the illuminant source and the floor as reference surface. Assume clearsky values. 3) Compare your desired lighting levels to those calculated for the reference surface. Determine if lighting levels are appropriate, are too great, or are not sufficient for the occupancy. A) If lighting levels are too great, discuss methods of reducing lighting levels. B) If lighting levels are not enough, discuss methods of increasing lighting levels. 4) Analyze building passive thermal performance. Consider only the Winter and Summer solstices at 5AM, 8AM, 12PM, 4PM, 8PM, and 11PM (or use six other more appropriate times when the building is set to be occupied for its intended use). Include heat gains (or losses) due to temperature differences, solar gain, infiltration/ventilation, and interior equipment and occupancy gains (ignore artificial lighting for now). Assume clearsky values. A) Calculate the steadystate floating interior drybulb air temperature. B) Calculate the steadystate floating interior and exterior envelope surface temperatures. C) Calculate the steady state floating Mean Radiant Temperature (MRT). 5) Prepare an electric lighting demand calculation for your project building for nighttime, and as supplement to daylighting calculation if daylighting is not sufficient associate to building occupancy (only provide the lighting needed when the building is occupied for the intended use) and the selected times of day for analysis. 6) Design a lighting plan for your building. Prepare drawings (plans, sections, elevations) showing and labeling the system components. A) Label the lighting equipment components. Use the textbook and outside sources for guidance in how and where to show equipment and equipment connections and mounting. B) These drawings will require additional information to be added to in the following sections; please be sure drawings clearly communicate your intent. 7) Convert electrical lighting demand to total energy absorbed by the building interior and add this to your building's internal heat gains via heat balance (heat gain calculations per Part 2, Section 4). 8) Calculate total mechanical load (heating or cooling) for the times analyzed. 9) After determining the steady state performance of your building, establish parameters for selecting appropriate mechanical systems to augmenting the floating condition when necessary. Prepare a narrative description of your process. A) Consider volume of structure. B) Consider envelope construction. C) Consider occupancy needs and restrictions. D) Consider available space for systems integration. E) Consider passive heating and cooling techniques and technologies. 10) Select a mechanical system for inclusion to your project. Prepare a narrative discussion identifying the system and it's components and of the implications of your decision; including possible design changes needed to implement your decision. 11) Calculate the approximate cost to operate the mechanical system for the two days analyzed. Extrapolate for annual values. 12) Prepare drawings (plans, sections, elevations) showing and labeling the system components. A) Label the mechanical equipment components. Use the textbook and outside sources for guidance in how and where to show equipment and equipment connections and mounting. B) These drawings will require additional information to be added to in the following sections; please be sure drawings clearly communicate your intent.
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13) Prepare a discussion of plumbing, electrical, and life safety systems traditionally installed in Western buildings and how they may impact your building design. Be sure to cite any data and research in your discussion. 14) Prepare a discussion of plumbing, electrical, and life safety systems alternatives to the traditional and/or industry and professional standards that may incorporate nonWestern or sustainable/green methodologies that you would explore as a practicing architect. This will require some research. Be sure to cite any data and research in your discussion. 15) Prepare a project summary (conclusions) describing the process completed, the changes to your design you may now want to embark on depending upon your project's thermal and visual performance, and other outcomes you may expect at times not specifically measured or calculated (extrapolate on your results). Also discuss the difference between these steadystate calculations and how realtime results may differ based on your building design and envelope assemblies. Reference course material such as the Laws Of Thermodynamics, solar geometry, thermal mass/lag/inertia, and principals of passive thermal and solar design, daylighting, and active building systems. 16) Extra Credit  Evaluate this course A) Identify strengths of the course: material, reading (reader and texts), homework, handouts, quizzes, project, etc. B) Identify limitations of the course: material, reading (reader and texts), homework, handouts, quizzes, project, etc. References These are the minimum references to be used in the implementation of this project. Other references and research material should be consulted. Textbook References B2 Climatic Conditions for the United States B3.1 Solar Intensity and Solar Heat Gain Factors 32° N Latitude Conventional Units B4.1 RValues of Air, B4.2 RValues of Typical Building Materials B4.3A Overall Coefficients of Heat Transmission of Windows and Skylights B5.1 Rates of Heat Gain from Occupants of Conditioned Spaces B5.6B Recommended Rate of Heat Gain from Selected Office Equipment B5.6C Rate of Heat Gain from Miscellaneous Appliances B6.2 Air Changes/Hour Infiltration B6.3 Outdoor Air Requirements for Ventilation Commercial B6.4 Outdoor Air Requirements for Ventilation Residential Other References AR 425 Summary Psychrometric Chart Solar Protractor ASTM E424  71 Solar Energy Transmittance and Reflectance of Materials IES Lighting Handbook Reference Volume Daylighting Architectural Graphic Standards, Charles George Ramsey and Harold Reeve Sleeper Building Construction Illustrated, Francis D. K. Ching and Cassandra Adams Microsoft Excel software
Hints Please do not wait until the end of the semester to begin. Begin slowly, methodically, and rigorously set aside several times each week to work on the specific tasks of this project. Information must be presented clearly, showing work and identifying assumptions. Difficult to read, unclear, and unprofessional work cannot be thoroughly graded.
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