Despite this, it is standard practice in the UK for such products to be treated with preservative. BS EN 942 specifies the requirements for pressure treatment of softwood joinery. Internal joinery does not generally require preservative treatment. Larch and Douglas fir are often chosen for specialist structures and for their inherent durability when selected for cladding. Spruce, or whitewood, is used in many structural applications.
Moisture content is crucial to durability.
Wood is dried to a specific moisture content. Check with your supplier that the wood you are buying meets these standards. For exterior applications, you should ensure that all surfaces and ends are sealed to prevent moisture ingress. One of the main issues driving environmental regulation and concerns in government, industry and the public, is related to carbon emissions. Emissions, such as carbon dioxide and methane, are the major contributors to global warming.