The Australian residential building industry is on a positive growth path thanks to improvements in home affordability driven by new technology that helps raise production efficiency. New materials and building methods are gaining popularity; however, misconceptions exist about alternate forms of house construction techniques.
A new white paper by MiTek Australia examines the three mainstream types of residential building methods popular in Australia: timber prefabrication, ‘stick’ roof construction, and steel framing, and how they fare in light of changed market conditions and new building standards.
Architects face the challenge of designing a home that will not only withstand the test of time, but also meet budget, environmental and energy usage considerations. Before selecting a construction method and material, architects must first understand the role each plays in improving thermal performance, as well as its durability, cost effectiveness and environmental impact.
Prefabricated timber framing contributes to sustainable development by using a cleaner and more resource saving production process while displacing the more fossil-fuel intensive construction materials such as concrete and steel.
While ‘stick-and-brick’ construction does use timber in the roof and therefore shares similar environmental advantages as prefabricated timber frames, the volume of bricks often used for external and internal walls, potential for material wastage and the considerably longer time taken to construct on-site, all impact heavily on its green efficiency.
Being 100 percent recyclable and lightweight to transport, steel is often promoted as an environmentally preferable material, classified as such in several green building programs. However the production and use of steel framing results in a number of adverse environmental outcomes that greatly exceed the impacts of available renewable alternatives such as timber.
In terms of thermal performance, advocates of timber frame construction have long argued that timber frame houses are more thermally efficient and therefore more cost effective to heat. Steel on the other hand, is a heat conductor with extensive studies in North America indicating the thermal bridging that occurs with insufficient sheathing can reduce the effective ‘R’ rating of walls by as much as 50 percent compared to the same timber framed wall assembly.
In the on-site Vs. off-site argument, the latter is on a winning wicket given that prefabricated techniques and sustainable materials save on time and labour while allowing specialist fabricators to build to exact specifications. Though more expensive than stick framing, the cost of timber prefabrication is offset by its quick installation time.
Following a complete assessment of all three building methods, the white paper finds timber prefabrication as the ideal engineered solution that can help significantly reduce project costs and build time, increasing the affordability factor.
To download the white paper, click here.