Proposal for Change to NCC – DTS Solution for Timber Construction up to 25m in Height (Class 2, 3 & 5 Buildings)
Forest and Wood Products Australia Limited (FWPA) has prepared and submitted a proposal-for-change (PFC) to the Australian Building Codes Board (ABCB) to create a voluntary deemed-to-satisfy (DTS) solution for the Building Code of Australia Volume 1 (BCA 1) for the use of timber building systems in Class 2 (apartments), Class 3 (hotels) and Class 5 (office) buildings up to 25 metres in effective height (approximately 8 storeys).
Currently, timber building systems are restricted to 3 storeys under the NCC DTS provisions with taller buildings requiring an ‘alternative solution’ to design.
The proposed solution will cover both ‘timber framing’ and ‘massive timber systems’ and will consist of the use of appropriate layers of fire resistant plasterboard and sprinklers.
The PFC was submitted on the 2nd February 2015.
Under the Building Code of Australia Volume 1 (BCA) timber framing in Class 2 (apartment) & 3 (hotel) buildings is restricted under the deemed-to-satisfy (DTS) provisions to a maximum of three (3) storeys or 4 storeys over a concrete/masonry carpark. Buildings higher than this can be constructed (e.g., Melbourne’s 10-storey Forte building) but are required to be assessed under an ‘alternative solution’ approach which can be costly and time consuming.
In comparison, in other similar socio-economic countries, accepted timber building heights exceed 3 storeys. If approved, the code change will bring it in line with international codes and standards that have permitted similar opportunities for developers for more than ten years.
If this DTS solution can be secured within the BCA, it will provide many benefits for the broader community and for the building sector, including the following.
- A significant improvement in life safety and property protection and reduced risk to firefighters through earlier suppression and improved containment of potential flashover fires through the use of sprinklers and fire resistant plasterboard.
- Increased construction material choice and opportunity for more innovative and diverse designs and therefore a broader and more competitive environment for consumers and developers.
- Reduced ‘alternative solution’ compliance costs for business and administrative costs for government.
- Improved affordability as local and overseas experience has demonstrated savings due to the following:
- reduced construction times (structure & follow on trades: plumbing, electrical)
- reduced crane costs
- reduced requirement for foundations
- reduced truck transport movements
- reduced neighbour disruption
- reduced OH&S incidents and costs
- Improved environmental outcomes
- recognised through Life Cycle Assessment (LCA) studies, wood products have less embodied energy, are responsible for lower air and water pollution, and have a lower carbon footprint than other commonly used building materials.
- reduction in carbon dioxide emissions through the carbon stored in wood products and avoided emissions from alternative building materials.
Key dates in the process are as follows:
Submission of PFC to ABCB – 2nd February 2015
Initial assessment of PFC by ABCB’s technical committee – March 2015
Release of Public Comment Draft of BCA – mid 2015
If supported, changes made effective in BCA – 1st May 2016
In summary, this proposal for change will give building developers/professionals the option of using a deemed-to-satisfy solution, which will provide the following additional benefits:
- Provide a safer fire solution through the use of sprinklers and fire resistant plasterboard.
- Create greater choice for building developers without the cost and time delays due to the use of ‘alternative solutions.’
- Deliver more sustainable buildings and affordable construction solutions.
- Align the Building Code of Australia with international best-practices.