Thermally Modified Timber: The first piece of domestic furniture


The Grown in Britain campaign is a year old, and that year has flown past. In that time we've seen some huge steps forward in building a healthy British timber industry, and we are really honoured to have played our part. Of course, we're still ticking along doing our thing with coppiced timber and other exquisite British hardwoods, but we're really excited about being invited to experiment with a 'world-first'. 

Our chum James of Tyler Hardwoods has been thermally modifying British timber; which sounds very scientific, but the principle is very simple. You take a hardwood, and bake it at around 180 degrees. This makes the wood resistant to rot and more stable. His big idea (and it's one we really like) is to replace the use of sapele and other imported tropical timbers (sapele or iroko are used because they are very durable and rot-resistant) in external joinery. 

We think it'd be fantastic to see low-value English beech or sycamore thermally modified and given a new use, so when James phoned to ask us if we would be interested in making an experimental piece in some we jumped at the chance. The very next day a pallet of 'TMT' ripple sycamore arrived. James is a very efficient chap. So we set about making a piece that was super-simple and, as always, let the timber do the talking. The wood smells of toasty coffee, so we were inspired to make a coffee table.   

The results: Well, as you can see it's a very beautiful timber, almost walnut in colour, and the ripples look just as good as they do in white sycamore. And as I've said, it also smells fantastic - smoky and toasty. It is slightly harder to work as it's more brittle as a result of the baking process, which also slightly compromises the wood's strength. 

These properties aside, a major question mark for me is the embedded carbon. This is unknown at this stage, but I'd imagine higher than kiln-dried timber.

While it might be very justifiable to use TMT in outdoor furniture or external joinery because of its resistance to rot, it seems a little indulgent to use it in internal furniture just because it has a lovely colour and smell. However, we might find that the carbon embedded in the baking process is relatively low, so I'm reserving judgement on this until I hear back form James with some data.

We're really excited about the future of TMT and hope to see this material appearing on shop shelves; finding a use for low-value beech and sycamore, and replacing questionable tropical hardwoods. It's been really fantastic to have made the world's first thermally modified ripple sycamore table - it isn't often that you get to do something that's really new with wood. It's a very old material, and most things have been done long ago.

Brogan Cox