WOOD YOU USE TIMBER?
All windows, whatever the material, need regular maintenance
Social landlords need to invest for long-term financial value as well as to recognise their wider responsibility towards the planet. Here Tony Pell, Chair of the Wood Window Alliance, explains why. wood industry has T hechanged significantly over recent years. There was a time, not that long ago, when the industry supplied not windows, but primed frames to be glazed and painted on site. The focus was on cheap timber, which needed regular sanding and recoating to avoid premature rot. How times have changed. Over the last 10 years or so, there has been a revolution in the
way we make high-performance wood windows in the UK, from the use of engineered slow-growth substrates, to full factory finishing with advanced coating systems and double- or triple-glazing. Today’s factoryfinished wood windows deliver unbeatable energy performance, exceptional durability and minimal maintenance – all with a much lower impact on the environment than PVC-u.
Does the world need more plastic? Well, perhaps if it’s cheaper Of course, whether planning new or refurbishment projects, social landlords are looking hard at all costs, including the cost of maintenance regimes. So, seeing PVC-u windows are cheaper to install than wood, and making an assumption about maintenance costs, they could be forgiven for believing PVC-u offers better long-term value.
Long-term value A study1 by Heriot-Watt University shows that wood actually provides better value than PVC-u in the long-term, thanks to the wood frame’s longer life and extended maintenance cycle.
The typical recoating cycle on a pale opaque finish is eight to 10 years – with minimal preparation and just one or two topcoats to restore the window to pristine condition
The study shows that factoryfinished wood window frames made to WWA standards have roughly twice the planned service life of equivalent PVC-u frames – 56 to 65 years for wood against 25 to 35 years for PVC-u.
Low maintenance All windows, whatever the material, need regular maintenance. The difference between wood and PVC-u is that the wood coating needs to be refreshed periodically, whereas PVC-u windows will tend to age and discolour until they are replaced. Anyone used to the sort of repainting regimes associated with traditional wood windows will be in for a surprise. The typical recoating cycle on a pale opaque finish is eight to 10 years – with minimal preparation and just one or two topcoats to restore the window to pristine condition.
Better LCA The study shows the wood frame to have significantly lower lifecycle impacts than an equivalent PVC-u frame, particularly when it comes to Global Warming Potential, when the wood frame saves 160kgs CO2e when used instead of the PVC-u frame. In an average property, you can save at least five tonnes of CO2e just by choosing wood windows and doors instead of PVC-u.
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