Taking the heat off net-zero housing plans

We are on the cusp of a housing refurbishment revolution in the UK as the government looks to overhaul the country’s energy-inefficient housing stock with a host of net-zero plans. Much focus and most headlines are given over to the push to replace gas boilers with heat pumps. It’s a logical move, especially with sky-rocketing energy prices. Our own industry is also being targeted, with questionable amendments to building regulations that will even limit large windows to try and keep homes cool. An argument is also current raging about amendments to the ventilation requirements in windows. This is an area that has not gone unnoticed by Britain’s favourite grand design guru Kevin McCloud. 

His latest outburst is perfectly logical and supports the argument many in the fenestration industry have been relaying to government. He claims the UK should be focusing on insulation, ventilation and shutters instead of heating. Speaking ahead of the Grand Designs Live event in London, he said: “The classic pratfall is that you look at the market, you say how can we make it greener, what technology can we bolt on to it to make it green? Oh, let’s go for heat pumps. When, actually, if you said insulate, make it airtight and put in a mechanical ventilation with heat recovery system, many homes would require very, very little extra by way of energy input.”

Insulation and ventilation are far more constructive areas to focus on. Concentrating on new ways to create heat is counterproductive. The topic of ventilation has caused much debate within our industry and there is a middle-ground solution to ensure homes are ventilated while remaining insulated. When I hear that new regulations will limit the sizes of windows in an order to prevent homes from overheating, I can only think back to Victorian times when windows were bricked up to avoid paying a window tax. Modern, energy-rated windows provide able insulation, while also allowing inhabitants to benefit from natural light. Innovative new vacuum glazing can even achieve U-values as low as 0.7W/m2.k. McCloud also made an interesting addition to the debate when he said that instead of limiting window sizes, we should be looking at exterior shutters to help reduce heat loss: “As we get warmer in the summers we will end up with more shutters like they do in Italy on the outside of buildings. If you look at Regency buildings in Britain, which were fitted with balconies, and Victorian buildings, and Georgian houses, they had exterior blinds. We’ve lost a lot of technologies which, historically, were already there.” It all adds to the argument that improving insulation is the most logical solution; we should not be focusing on new ways to create more heat. The area of shutters is also interesting and offers an opportunity for further added-value items to the sale of windows. I may not support their actions, however I think “Insulate Britain” definitely had the branding right… 

John Cowie – Editor Windows Active