1kg of (oven-dried) wood contains approximately 0.5kg of carbon, which represents approximately 1.8kg of absorbed carbon dioxide for each kg of construction timber used. If wood is used in timber products there is a further increase in net uptake as its sequestered carbon continues to be stored for as long as the products remain in use. Additional uptake occurs if the area of forest increases, but if the area decreases there is likely to be a net outflow of CO 2. If the area of forest remains constant, there is a net uptake of CO 2.

The carbon is then partly released back into the atmosphere when trees die and decay, with a proportion being retained in the soil and forest biological systems. This is stored as carbon in wood, bark and leaf material. Carbon dioxide in this context includes all the greenhouse gases rolled up into a single quantity referred to as carbon dioxide equivalent (CO 2e).ĭuring the production of timber, trees absorb, or sequester CO 2 from the atmosphere during photosynthesis as they grow. The embodied carbon of a material is the net carbon dioxide (CO 2) emissions produced during the processes involved in its production and disposal. They were the early drivers for the responsible sourcing standards. Certification schemes, such as the ‘Forest Stewardship Council’ (FSC) and the ‘Programme for the Endorsement of Forest Certification’ (PEFC) have been in existence since the 1990s.

Timber certification schemes, requiring responsible forest management, play an essential part in this approach. Therefore, increasing use of responsibly sourced timber in construction can help to maintain and increase the forest resource. One of the main drivers for afforestation is increased demand for timber products. What is it like to be a structural engineer? Continuing Professional Development (CPD)

Timber and stone construction