Forrests cover 30% of the world's landmass. Second to the oceans they are the largest carbon sink on earth and a vital part of the planet's natural carbon balance. Globally, deforestation continues at an alarming rate, but it's largely confined to tropical hardwood forests. In Europe, our forests have grown by an area about the size of Greece in the 15 years between 1990 and 2005, and that growth continues at the rate of 661,000 hectares a year, roughly three football pitches every hour of the day and night. Europe's forests alone provide a carbon store of between 150 and 200 billion tonnes of carbon dioxide, sinking an additional half billion tonnes every year, and they produce over 90% of all the wood we use in Europe. What's the best way of using Europe's growing forests to help tackle climate change? Use more wood. Trees grow by photosynthesis as they grow they absorb carbon dioxide and produce oxygen. When they are harvested most of the carbon dioxide stored in the tree remains stored in the wood product. Because Europe's forests continue to expand the carbon stored in the wood product is a clear additional gain. This is the carbon sink effect that means wood is better than carbon neutral, so that the more wood you use in a building the lower its carbon footprint. In Europe the carbon store of wood products keeps over 220 million tonnes of carbon dioxide out of the atmosphere, an amount which is increasing by around 20 million tonnes a year as the volume of wood products increases. Using more wood also helps increase the carbon sink effect of the forest. Because mature trees which absorb less carbon dioxide are replaced with vigorous new trees as required by law throughout Europe and a prosperous market encourages investment in future growth. But using wood products has even greater benefits for reducing greenhouse gas emissions in construction. Because wood products are better than carbon neutral the more wood we use from sustainably managed forests the more carbon dioxide is removed from the atmosphere. Add to this the savings made by using wood instead of energy intensive materials like concrete bricks, steel and aluminium and wood products can have a really significant effect on greenhouse gas emissions. Every cubic metre of wood used instead of other construction materials saves around one ton of carbon dioxide. The carbon benefit of wood products can be enhanced by extending the life of the product through good design and regular maintenance, reusing products like pallets, flooring, panelling and beams, recycling and by using waste and end of life wood as a carbon neutral biomass fuel. Wood is the natural solution to low carbon construction. A carbon indicator has been developed by the Edinburgh Centre for carbon management to identify the carbon savings to be made by using different materials. A three bedroom detached brick and concrete block house has a carbon footprint of 20 tonnes of CO2. Just replacing the concrete blocks with timber frame saves three tonnes. Even bigger savings can be made by greater use of wood internally and externally including floors, windows and timber cladding up to 86%. This school uses solid timber as its primary structure. The carbon indicator showed a negative materials footprint of minus 40.9 tonnes of carbon dioxide because of the solid wood. Research in Sweden compared the carbon dioxide balances for two four-story buildings, one with a timber frame and the other with a concrete frame over a hundred-year period. The concrete frame building showed emissions of around 96 tonnes of carbon dioxide while the timber frame building showed a net uptake of 150 tonnes of carbon dioxide. And because of woods naturally low thermal conductivity, timber frame buildings don't need as much extra insulation to be highly firmly efficient. So using more wood is one of the simplest ways to build a low carbon economy and help tackle climate change. It produces beautiful, healthy, durable products, encourages sustainable forestry and delivers significant reductions in carbon dioxide emissions. Tackle climate change, use wood.