Using wood delivers major environmental benefits. There is no other commonly used building material that requires so little energy to produce as wood. Trees capture CO2 from the air and combine it with water from the soil to produce wood that locks in the carbon until it decays or is burned. Not only is the production and processing of wood highly energy-efficient, giving wood products an ultra-low carbon footprint, but wood can often be used to substitute for high energy demand products like steel, aluminium, concrete and plastic. Every cubic metre of wood used as a substitute for other materials reduces CO2 emissions by an average of 1,100 kg. Adding the CO2 stored in wood each cubic metre saves 2,000 kg CO2.
So wood offers these carbon footprint environmental benefits but when combined with preservative treatment the carbon is locked up in the wood for much longer because the wood is protected against decay, and when appropriate, fire. Life cycle assessment (LCA) of treated wood components in buildings demonstrates how these advantages can be quantified and utilised in real projects.
LCA looks at a wide range of environmental impacts including, for example, climate change, water use, human toxicity and waste disposal. When these impacts are assessed for wood components protected against decay by preservatives, they achieve the A+ rating (lowest environmental impact)2. Specifiers and designers help to protect the environment long-term by using such materials in their projects.
References
1. Tackle Climate Change: Use Wood CEI-BOIS
2. WOOD, BUILDING THE BIOECONOMY
3. The Green Guide to Specification. BRE Centre for Sustainable Products 2015
4. NTR A – better or less good than other materials
5. LCA – NTR Treated Wood Decking and other Decking Materials