Today’s timber windows are vastly improved on their predecessors, but a recent survey and round table found that specifiers’ misconceptions are still making them wary, says Tracy Pomfret of George Barnsdale
Rishi Sunak’s U-turn on attending COP 27 came to late to avoid sending a message to other nations that the UK’s short term financial pressures are more serious than the long term survival of the planet. There are echoes of this within the construction industry; a wide acknowledgement that we need to be building more sustainably, but when it comes to the bottom line, many of us are still not prepared to put our money where our collective mouths are.
Timber windows are ‘carbon negative’ – there is no argument that timber windows and doors are the most sustainable option for the planet, and a recent survey we undertook shows architects agree, with 98% of respondents saying they preferred to choose sustainable materials. However, only 5% said they were specifying timber for windows on a weekly basis. Furthermore, one fifth of them said they were actually specifying less timber than they were five years ago.
Aluminium is the material of choice – 84% said they specified it most regularly even though it is not the most environmentally friendly option. Despite it being almost fully recyclable, the growth in demand for aluminium means that, in reality, only a third can be supplied by recycling with the majority still coming from source (Bauxite mining).
Unlike timber (via FSC certification), there is currently no legal requirement in the UK for aluminium, used in construction, to have a chain of custody in place to demonstrate responsible sourcing. This is addressed to an extent by some of the building assessment schemes like BREEAM but dubious practices still go on in the mining industry, and there are no guarantees they aren’t part of the UK supply chain.
Researchgate.net has calculated that an aluminium window creates four times the amount that a timber one does.
Analysing the survey results, it was important to understand why there is such a gap between good intentions and delivering an environmentally friendly build/renovation. To this end, a round table event was hosted in Manchester with architects and practice owners working across commercial and residential projects.
Round table results
One of the overriding sentiments is that clients want to be sustainable, but it has to be at an acceptable price point. Architects were unanimous in their wish to be sustainable, and were regularly suggesting timber options to clients. However, they were often met with objections; timber is perceived as being expensive and is one of the easiest things to save money on, with clients opting for “posh PVC” instead.
Further evaluation of the discussions that took place demonstrated that price wasn’t the only concern people had. As an industry, timber window companies are still battling with the same misconceptions surrounding aesthetics. The project ‘had to suit timber windows,’ and timber wasn’t readily associated with contemporary projects.
Some of the architects blamed fads and fashion, with TV shows promoting large bi-fold doors, for example. Again these are perceived to be unsuitable for timber, so architects “end up sleepwalking into aluminium.”
Busting the durability myth
Another misconception is timber’s durability. Many are still under the impression that not only does timber not last, it is both difficult to maintain, and can move and twist over time.
Most of the architects currently only consider timber on projects where they need to match to existing or where there is a planning requirement, for example a historic project.
Few of the participants seemed to be aware of the advances made in timber fenestration in the past 20 years – the fact that, made to Wood Window Alliance standards, they can last up to 80 years, compared to 35 years for PVCu.
Companies working to the tested standard use sustainable, defect-free engineered timber which prevents twisting and warping and is strong, stable and an excellent substrate for the advanced coatings. They also incorporate optimal designs and processes with water shedding angles on cills and beads, end grain sealing and the use of microporous paint that lasts up to 10 years without needing to be recoated.
The legacy of poorly made wooden windows of the past still hangs heavy in the minds of most clients, and it would appear that architects don’t feel confident enough to argue this with them.
It is clear that the high performance timber windows industry has not done a good enough job of educating architects about the benefits of modern timber windows, the fact that they can last twice as long as PVCu, the technology and tested performance they deliver, the long guarantees and low maintenance required. Nor have they provided architects with the inspiration to see timber windows in a contemporary light, something the Scandinavians, for example, have no issue with. It is time we stood up for the environment, by changing our approach to timber windows, and recognising their benefits in practice.
Tracy Pomfret is head of marketing at George Barnsdale