Reducing CO2 emissions

Growing trees absorb CO2

Wood is an extraordinary natural resource. It provides a high-performance building material without depleting the earth’s resources. It grows in forests and plantations which clean the air, creating the conditions that make the planet habitable, while providing a natural habitat for leisure and wildlife. On average, trees absorb one tonne of CO2 and release almost three-quarters of a tonne of oxygen for every cubic metre’s growth. The CO2 is stored in the wood as carbon. Young, active trees replace the mature trees, absorbing yet more CO2.

Wood products store CO2

Throughout their life, wood products continue to store the carbon sequestered by the harvested trees. Further CO2 gains can be achieved by extending the life of the wood product, by recycling into panel products, and by recovering the energy in the wood at the end of its life by using it as a biomass fuel. Managing a forest sustainably means ensuring new trees replace the harvested trees. So the forest maintains its carbon store. And the amount of carbon stored in the product made from the harvested wood is a net gain. This means the wood can be described as 'carbon negative' – it stores more carbon than the equivalent CO2 it emits from the harvesting, processing, transport and fabrication. This helps reduce the growth of CO2 in the atmosphere, slowing down climate change.

Substituting wood for other materials reduces CO2 emissions from construction.

Using wood in construction is a good thing in itself. Its effects are even more positive when the CO2 savings made by not using other construction materials are taken into account.

Substituting a cubic metre of wood for other construction materials (concrete, blocks or bricks) results in an average saving of 0,7 to 1,1 tonne of CO2.

Edinburgh Centre for Carbon Management

Wood has lower CO2 emissions than any other building material. The wood industry is also one of the biggest users of biomass energy, often contributing excess energy to national grid networks. Even the recycling of materials such as steel and aluminium, whilst a necessary part of modern materials production, still requires large energy inputs compared with wood.

CO2 emissions will vary by country, depending on the predominant energy source. China’s energy production is heavily dependent on coal, which produces high levels of CO2 emissions.

Wood buildings have lower CO2 emissions throughout their life

Saving CO2 emissions from the construction phase is just one part of the story. At the moment around two-thirds of a building’s CO2 emissions come from the in-use phase. Because of wood’s naturally low thermal conductivity and the capacity for low cost, effective insulation, wood construction provides a competitive way to achieve higher energy-efficiency. As the walls do not have to be so thick to achieve good insulation, houses built using wood have more livable space.

Cradle to gate carbon footprints for materials used in construction, Edinburgh Centre for Carbon Management
Using wood products slows the rate of global warming
Wood frame apartment building, Europe
Zero carbon demonstration house, Europe