If we go back into time, timber was probably the only option for medium and large scale construction, until the advent of steel; concrete has been around for a very long time, but ultimately timber was the best option for most purposes.
Large scale timber construction has never totally gone away, but steel and concrete have monopolised the market, to the point that most people do not even consider a timber option.
Fire is often cited as a major problem for timber, but in fact it has well known char and failure rates. In other words when it comes to fire in buildings, many firefighting professionals would prefer to tackle a timber building, because they can forecast its progress. Steel buckles very quickly in fire situations and does so unpredictably.
A more recent addition to the options for timber is Cross Laminated Timber, CLT.
Essentially these are massive sheets of plywood, cut exactly to shape and size in a factory, and deliverd to the building site as panels that are easy to assemble.
Window and door openings, plumbing and electrical systems can all be fitted on or into these panels, giving a large ‘Meccano’ style package that literally slots together.
The benefits of CLT are significant. In terms of overall cost they can be extremely effective, because the speed of site assembly is so rapid, but here’s some other key features:
Noise There’s so much less noise during construction. No grinding, cutting, welding. This improves the whole process for neighbours.
‘Wellness’ Because it is virtually 100% pine or spruce, CLT exudes natural resin aroma; it’s got a softness that absorbs sound and generally improves the whole ambience of the building
Heat Insulation Timber has excellent thermal properties and CLT panels can easily create extremely low heat loss factors.
Less Foundation Because CLT structures are far lighter, you need far less material to create the foundations. It’s also easier to span obstacles (tunnels, drains, etc).
Environmental Benefits The biggest benefit of all is that fully sustainable ‘farmed’ spruce & pine are already growing in Europe, Canada and elsewhere at such a rate that there’s more than enough timber to build all the housing we need, with no side-effects or risk to virgin forests.
Even more excitingly, trees absorb CO2 as they grow; in fact, younger trees absorb more than mature ones, so continuous growing and harvesting actually improves CO2 absorption. Timber has the potential to be a massive part of the answer to CO2 reduction.
In contrast, cement production is responsible for 8% of global CO2 emissions.
What we have to do is to return to our previous belief and faith in timber as a reliable construction material. We’ve built up a ‘memory footprint’ that sees concrete and steel as the solutions, when in fact timber has always been the answer!
For more information feel free to contact me or listen to this episode of Tom Heap’s 39 Ways to Save the Planet on Radio 4.
Photo Credits: Piveteaubois & Eurban