Prefabricated engineered timber is greener than concrete and steel
The built environment is responsible for a third of global greenhouse-gas emissions by some estimates. The largest part of a building’s carbon footprint results from its lifetime energy use, and the next biggest part derives from its construction. The manufacture of concrete and steel accounts for an estimated 10 percent of greenhouse-gas emissions. Trees, however, are “carbon sinks”—they sequester or hold carbon, even after the timber is milled and processed. According to a study in the Journal of Sustainable Forestry, substituting wood for other materials used in the built environment could prevent up to 31 percent of global carbon emissions. Engineered timber buildings can be dismantled and the timber recycled with relative ease.
Lower Embodied Energy
Engineered timber has great sustainability credentials, and not just because wood is a renewable resource. Trees sequester carbon while they are growing, but wood continues to store carbon for its lifetime, which makes engineered timber extremely low in embodied energy – the energy consumed by all of the processes associated with the production of a building.
Less Greenhouse Gases
Australian research into the global warming potential (GWP) of a hypothetical office building constructed in conventional concrete and in engineered timber showed the timber building would create less than a quarter of the C02 of the concrete building.
An example of the potential of the tall timber method to radically reduce C02 emissions can be seen in International House in Sydney by Lend Lease and Tzannes Architects. The building structure is 100% timber above the ground level, including the lift cores, stairs, risers, floor slabs, roof and walls. The structural members of the building have been bolted and screwed together, meaning at the end of project life the structure can be dismantled and the timber elements reused.
International House represents the closest net zero emission construction that has been achieved to date for any commercial building across the Tasman.
Tallwood’s building components are manufactured to size so the significant wastage typical in traditional construction methods is all but eliminated. To ensure this, we ask designers who collaborate with us to design to a 600mm spatial grid, the underlying framework of most building materials to minimise ‘offcuts’.
Less Truck Movements
When you build in a conventional way your materials are brought to site, truckload by truckload, from a number of suppliers and over a lengthy period of time. Building with Tallwood reduces the number of materials – and therefore suppliers – you need, and consolidates many processes into a few. Combined with faster build times this all adds up to a radically reduced number of truck movements needed to complete a project. Less truck movements has obvious cost and environmental benefits, and also cuts down on the disruption to the neighbourhood you are working in.