Using more wood in construction and renovation to turn our built environment from a climate problem into a climate solution is predicated on there being enough wood and wood fibre to do this.

First and foremost, this supply of wood has to be sustainable. For our timber supplies to be deemed sustainable the wood must be sourced from a managed forest where natural regeneration of the forest is viable or where new trees are planted as others are felled. Such replanting needs to see between 5,000‒10,000 saplings planted per hectare, replacing around 500 felled trees per hectare. The forest ecosystem is required to be regularly monitored to ensure it remains in good health and able to provide for both people (employment, recreation) and nature (biodiversity) now and into the future. A certification scheme accompanies this process of which more than 50 exist worldwide. Of these, the Forest Stewardship Council (FSC) and the Programme for the Endorsement of Forest Certification (PEFC) are the two best known. While both schemes are committed to the same cause – sustainable forestry – the primary difference between the certifications is their origins. Initially the FSC scheme was developed for tropical environments and not suited for forests in Europe and North America. This led to the introduction of PEFC in the late 1990s to facilitate sustainable forest management (SFM) certification in Europe. PEFC now accounts for over 264 million hectares of certified forests, 10 per cent of the world's forest area, and its certification system is recognized in over 30 countries. Meanwhile FSC has certified forests in over 80 countries with 7 per cent of the world's forest area (180 million hectares) carrying the FSC certification. Fifty per cent of people in the UK recognize the FSC logo in relation to buying wood products.