The message is clear: Build with carbon

15 October 2014


Dave Hopkins, executive director of Wood for Good, says the UK’s housing needs could be met at the same time as capturing more carbon.


The UK government has started to make investments from the £1bn pot it has set aside to fund Carbon Capture and Storage (CCS) projects - largely unproven and expensive technology which seeks to lock away CO2 emissions.

While I would never argue against the development of new green technology, I would like to see at least a portion of that budget go towards investing in a CCS solution that we already have in abundance - trees.

Stay with me on this.

Sustainable forestry practices harvest trees at the peak of their growth and carbon sequestration ability, replanting them with more trees in a continuous, renewable cycle. That carbon is stored indefinitely in the wood products produced from the harvested timber.

This natural, proven carbon storage ability strengthens the argument for an increased use of timber in construction. By using wood products in long-life applications, such as our built environment, more trees will be planted, grown and harvested before the timber product reaches its end of life. This provides for an emissions reduction and storage mechanism - with more carbon emissions being added to the store in each harvesting and each new building.

In fact, building with timber is the safest and cheapest form of carbon capture and storage available. We estimate it costs roughly £25-30 per tonne of CO2 captured and stored using mixed woodland forestry. In addition, by storing emissions in buildings we can turn a polluting liability into an asset and an appreciating one at that, as you could see your emissions accounted for in property, on balance sheet. Surely that has to be better than pumping them into the North Sea.

When you apply this to the UK's housing stock, the argument gets stronger. The UK is in dire need of new housing. We could meet this need while also capturing more CO2.

The Labour party has pledged to build 200,000 new homes every year if it gets into power in 2015 (a big IF). If that number of new homes were built with timber frames, we estimate that an additional 4 million tonnes of CO2 could be captured every year.

This maths is based on research conducted using Wood for Good's Lifecycle Database, which shows that an average three-bed, timber-framed house sequesters and stores roughly 19 tonnes of CO2 in its timber products.

Now, of course, not all housing needs will be met by building three-bed semi-detached housing as modelled in our study, but it gives you an idea of what can be achieved.

This is the rationale behind our new campaign to get the UK to build with carbon. Working with data visualisation specialists Carbon Visuals we've produced a series of animations which show the carbon in one tree, one hectare of trees, a house and a typical housing estate. Each image visualises what one tonne of CO2 would look like at normal atmospheric pressure - a sphere 33ft across. Hitting Labour's annual target would equate to a pile of carbon dioxide spheres far taller than the buildings of Canary Wharf.

We've also modelled some known timber structures. Bridport House in Hackney, for example - one of the UK's first multi-storey buildings to be constructed using only timber - stores a significant 1.1 million kg of CO2.

We've designed the animations to be understood by almost any audience and we'll be showing them to construction industry audiences, policy makers and the general public. I'd welcome you to visit our website, www.woodforgood.com, and see for yourself.

Now, just suppose that the UK's £1bn CCS budget was spent entirely on commercial forestry. It would allow for the planting of approximately 1.1 billion trees, covering 500,000ha and capturing 36.7 million tonnes of CO2 per year.

Not a bad investment in my book.

This image shows the carbon dioxide in one house