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GUIDELINES FOR CARPORTS & AWNINGS

Methods of Compliance

OPTION 1: DEEMED TO SATISFY Figure 3.7.1.4(a) Building Code of Australia (Housing Provisions)

CARPORT MAY BE COMBUSTIBLE

Not less than 900mm Street OPTION 2: DEEMED TO SATISFY Figure 3.7.1.4(d) Building Code of Australia (Housing Provisions)

CARPORT MAY BE COMBUSTIBLE

Less than 900mm Not less than 900mm Street

OPTION 3: DEEMED TO SATISFY Figure 3.7.1.4(a) Building Code of Australia (Housing Provisions)

CARPORT MAY BE COMBUSTIBLE

Wall with an FRL 60/60/60

Less than 900mm Street OPTION 4: DEEMED TO SATISFY Figure 3.7.1.6(d) Building Code of Australia (Housing Provisions)

Minimum 500mm Less than 500mm & up to the allotment boundary provided: CARPORT MAY BE COMBUSTIBLE i. ii. 2 or more sides must be open Minimum of 1/3 of the perimeter open to

ROOF COVERING & ANY CEILING LINING MUST BE NON-COMBUSTIBLE

iii. No direct support Class 1 dwelling

iv. Non-combustible separation with Class 1 roof space. Street NB: A side is considered open if the roof covering adjacent to that side is not less than 500mm from another building or allotment boundary.

OPTION 5: DEEMED TO SATISFY Part 1.0.8 Building Code of Australia (Housing Provisions) - Alternative Solution

Less than minimum 500mm

CARPORT MUST BE NON-COMBUSTIBLE

Less than 500mm & up to the allotment boundary provided: i. a class 1 building is to be protected from the spread of fire through the use of noncombustible material. 2 sides not enclosed (roller doors, side panels & gates are considered enclosures). Boundary fences are not considered enclosures.

ii.

Street

iii. No direct support to the Class 1 dwelling.

RATIONALE FOR PERFORMANCE BASED ASSESSMENTS

The Performance-based BCA Building Code The Building Code of Australia (BCA) is structured to enable practitioners, designers, developers and planners the ability to pursue construction via the Deemed to Satisfy Provisions or alternative solutions in the design & construction phase for buildings. Primarily, the Deemed to Satisfy provisions should be adhered to, however where peculiarities exist through exceptional circumstances, or physical conditions, alternative solutions can be adopted to provide a similar outcome. The advantages of a performance-based BCA were seen as allowing cost savings in building construction by:

·

permitting the use of alternative materials, forms of construction or designs to the prescriptive requirements the innovative use of materials, forms of construction or designs permitting designs to be tailored to a particular building giving clear information on what the BCA is trying to achieve allowing the designer flexibility in the use of materials, forms of construction or design provided that the intent of the BCA is met (in other words, allow for flexibility provided the performance required by the BCA can be achieved); while still allowing acceptable existing building practices through the deemed-to-satisfy provisions.

· · · ·

Hierarchy of the Performance-Based BCA The performance-based BCA substantially includes the technical requirements from the previous BCA90, with a `peformance hierarchy' built around them. The hierarchy of the BCA is shown below.

Level 1 Level 2

Objectives Functional Statement Guidance Levels

Level 3 Level 4

Performance Requirements Building Solutions Deemed-to-Satisfy Provisions Alternative Solutions

Compliance Levels

Assessment Methods Documentary evidence described in Part 1.2 Verification Methods Expert Judgement Comparison to Deemed to Satisfay Provisions

The Building Code of Australia Hierachy

The following is an explanation of the terms used and how they operate in practice. At Level 1 are the objectives. These represent the reason the community wants a matter regulated. They are primarily expressed in general terms and usually refer to the need to safeguard people and protect adjoining buildings or other property. An example of an objective from the BCA is:

·

The objective is to safeguard the occupants from injury or loss of amenity caused by inadequate height of a room or space.

At Level 2 are the functional statements. These set out in general terms how a building could be expected to satisfy the objectives (or community expectations). An example of a function statement from the BCA is:

·

A building is to be constructed to provide height in a room or space suitable for the intended use.

At Level 3 are the performance requirements. These outline a suitable level of performance which must be met by building materials, components, design factors and construction methods in order for a building to meet the relevant functional statements and, in turn, the relevant objectives. The performance requirements are the core of the BCA and are the only parts of the Code with which compliance is mandatory. An example of a performance requirement in the BCA is:

·

A room or space must be of a height that does not unduly interfere with its intended function.

Level 4 contains building solutions that set out the means of achieving compliance with the performance requirements. The BCA provides for two methods that can be followed to develop a building solution:

·

At Level 4a are the deemed-to-satisfy provisions. These include examples of materials, components, design factors and construction methods that, if used, will result in compliance with the performance requirements of the BCA. An example of a deemed-to-satisfy provision in the BCA is: ceiling heights must not be less than 2.4m in a habitable room.

·

At Level 4b are the alternative solutions. The key to the performance-based BCA is that there is no obligation to adopt any particular material, component, design factor or construction method. An approval authority may still issue an approval if it differs in whole or in part from deemed-to-satisfy provisions described in the BCA if it can be demonstrated that the design complies with the relevant performance requirement. There are several means by which an approval authority can assess whether a building solution complies with the BCA. These are referred to as assessment methods and include the following: a. The use of Clause A2.2 of the BCA (Class 2 ­ 9) and Part 1.2 BCA (Housing Provisions) (Class 1 & 10). These Clauses allow the following evidence (in some cases subject to conditions) to be submitted in support of a proposal that a material, form of construction or design meets a performance requirement or a deemed-tosatisfy provision:

· · · ·

a report from a Registered Testing Authority a current Certificate of Accreditation or Certificate of Conformity a certificate from a professional engineer a current certificate issued by a product certification body that has been accredited by the Joint Accreditation System of Australia and New Zealand (JASANZ) a current Scientific Services Laboratory (SSL) Product Listing Data Sheet any other form of documentary evidence that adequately demonstrates suitability for use. Verification

· ·

b.

Another assessment method is referred to as a verification method. methods include:

· ·

calculations ­ using analytical methods or mathematical models; and/or tests ­ using a technical operation either on-site or in a laboratory to directly measure one or more performance criteria of a given solution.

In keeping with the flexibility provided in the performance-based BCA, designers are not restricted to using a listed verification method. Any other method may be used if the approval authority is satisfied that it establishes compliance with the BCA. However, in making a decision, an approval authority may have regard to the relevant deemed-to-satisfy provisions or verification methods provided for in the BCA. Where physical criteria are unable to be tested or modelled by calculation, the opinion of a technical expert may be accepted. This is referred to as the use of expert judgement. The final assessment method is referred to as comparison to deemed-to-satisfy. This method permits a comparison to be made between the deemed-to-satisfy solution and the proposed building solution. If it can be demonstrated to the approval authority that the building solution complies in an equivalent or superior way to a deemed-to-satisfy provision, then it will be deemed to meet the relevant performance requirement. Under this hierarchy an applicant can use any materials, components, design factors of construction methods that comply with the relevant performance requirement. For Australia, this is a significant move away from sole reliance on prescriptive requirements and is designed to encourage innovation and the use of new technology. However, the BCA still caters for those who prefer specific guidance, or wish to continue to use traditional building methods. The deemed-tosatisfy provisions of the BCA continue to provide detailed prescriptive methods for establishing compliance with the performance requirements. How the Performance-based System is Used The BCA successfully combines a dual approach. combined with a high degree of flexibility, so that:

·

It provides a strong degree of certainty,

if compliance is achieved with the deemed-to-satisfy provisions, a building proposal is deemed to have complied with the BCA, however if a building proponent wants to take an alternative approach, they have the opportunity to do so ­ on the understanding that their proposal must achieve the performance requirements of the BCA.

·

The first step in using the performance-based system is to choose the means by which the building proposal will achieve compliance with the BCA. This will be by either:

· · ·

a deemed-to-satisfy solution an alternative solution; or a mixture of deemed-to-satisfy and alternative solutions.

If an alternative solution is chosen, the building proponent must ensure that an assessment method is chosen which satisfactorily indicates that the alternative solution will meet the performance requirements in the BCA. The nature of the assessment method will vary depending on the complexity of the alternative solution. PERFORMANCE REQUIREMENT In providing proponents the ability to utilise an alternative solution for carports, reference is made to P2.3.1 ­ Performance Requirement of the Building Code of Australia (Housing Provisions). 'P2.3.1 Protection from the spread of fire: a. A Class 1 building must be protected from the spread of fire from: i. ii. another building other than an associated Class 10 building the allotment boundary, other than a boundary adjoining a road or public space. (See Figure below)'

TYPICAL AREAS OF POTENTIAL FIRE SPREAD

Street

Allotment Boundary Class 1 building Building other than an associated class 10 Class 10

Areas of potential fire spread

In essence, the performance requirement is primarily focused on protecting the class 1 dwelling from any spread of fire from other buildings on the site or from the property boundary. The effect of achieving 'openness' eliminates the ability of a structure (Class 10 Carport) with a combustible load to transfer over to the Class 1 structure. The following diagrams are examples of how to determine an open carport.

IDENTIFYING AN OPEN CARPORT

500 mm or more Allotment Boundary Roof covering & any ceiling lining must be non-combustible - see 3.7.1.6(d)(ii)

Class 1 building Carport

Timber post is acceptable on allotment boundary, however, wall cladding must be non-combustible.

Side of carport is considered open if no roof covering is over the hatched area, i.e - at least 500 mm from adjoining building or allotment - see 3.7.1.6 (d) (i)

Allotment Boundary 3m Open Class 1 Carport 6m = = Open = Carport Calculation Open side Perimeter 3+3 3+6+3+6 6 18

1 3 This carport satisfies the exemption criteria in 3.7.1.6.(d)

Side of carport less than 500 mm from the allotment boundary, therefore side is considered closed - see 3.7.1.6 (d)

CARPORTS - PERFORMANCE REQUIREMENT ALTERNATIVE SOLUTION - Comparison with Deemed to Satisfy. Where the Deemed to Satisfy provisions cannot be achieved due to design or physical constraints from existing structures or site conditions, an alternative solution (Option 5) can be utilised to satisfy the Performance Requirement of P2.3.1. A comparison to the Deemed to Satisfy provisions as an Alternative Solution results in a determination that the use of non-combustible materials provides an outcome no less satisfactory in pursuing the intent of P2.3.1. Where there is no possibility of achieving compliance with Part 3.7.1.6 (d) (i) and (ii) for carports, a comparison with the Deemed to Satisfy provisions as an alternative solution can satisfy the performance requirements by being no less affective than the Deemed to Satisfy provisions through the use of non combustible materials. The use of this form of construction will restrict the dissipation of fire from areas of potential fire spread to the Class 1 dwelling. Whilst not achieving strict compliance with the Deemed to Satisfy provisions of the Building Code of Australia (Housing Provisions) satisfaction of Part 2.3.1 can be achieved.

Updated: 23 June 2009

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