Timber production makes a positive contribution to reducing carbon emissions by being part of the short term carbon cycle that involves trees absorbing carbon dioxide from the air, releasing oxygen and storing the carbon in the wood.

Using trees for timber and other wood products in this way creates space in the plantations for replacement trees to sequester more carbon from the atmosphere, thereby providing a net increase in stored carbon (this is called carbon sequestration).

What little energy is needed to process and dry wood to make timber is commonly produced from sawmill residues such as bark and sawdust generated by converting a tree into sawn timber. Excess sawmill residue is either used in the manufacturer of long-life panel products such as particleboard or medium density fibreboard (MDF).

The carbon in the timber, which has been absorbed from the atmosphere,  is stored for long periods of time in an array of timber products such as timber framing.

When a home is demolished or renovated, waste timber that cannot be reused can be recycled into a range of products including particleboard. Timber not suitable for reuse or recycling can be utilised to generate renewable energy, releasing the carbon back into the atmosphere to be reabsorbed by the growing trees. Alternatively, Australian research is showing that end-of-life timber can store the carbon for very long periods of time in well-managed landfills.

The carbon cycle of timber and wood-based products (Source: CEI-Bios, European Panel Federation)

Only small amounts of energy are needed to process raw wood into framing timber compared to other major building products such concrete, brick and steel. Hence there are only small quantities of greenhouse gases emitting during manufacture.

Research by the Cooperative Research Centre for Greenhouse Accounting recently compared the difference in greenhouse gas emissions generated by timber products compared to common high greenhouse emitting alternatives. More than 25 tonnes of greenhouse gases would be saved if the timber products were used.

• For more information see Forests, Wood and Australia’s Carbon Balance.

Greenhouse gas emissions from the manufacture of different building building componenets in a family home (Source: CRC for Greenhouse Accounting)