Why is the government not pursuing proper real-world carbon reductions in new homes, asks our editor-at-large
The biggest threat to proper sustainable construction in the UK is not the laziness or greed of big developers. It’s not a lack of public interest or concern either.
I think it’s our Building Regulations.
The Climate Change Committee (CCC) has, not surprisingly, published its own targets for housing and construction. They’re ambitious and laudable. The government, meanwhile, is producing its own Future Homes Standard (FHS), which it is trumpeting as the delivery mechanism to reduce energy use in all new-build homes by 75-80 per cent by 2025 and which, importantly, will make all such homes ‘low-intervention’, meaning they are easily retrofittable to zero carbon.
Sounds good, doesn’t it? Not really. If the Conservatives hadn’t scrapped the Code for Sustainable Homes in 2015, all new building right now would have beaten the FHS hands down by about 20 per cent, according to my calculations.
If we’d been building to Code Level 6, which, 15 years ago, was Gordon Brown’s intention for 2016, we’d be improving on the FHS by maybe up to 45 per cent. Passivhaus standards go somewhat further in embarrassing the FHS. In choosing any of these routes it’s possible we’d already have been cutting 80 per cent of our domestic energy needs in new housing by, perhaps, 2020.
But we didn’t keep the Code for Sustainable Homes. As a result, not only did we lose a reasonably sophisticated building tool – some say it was too complicated and burdensome and they’re right in parts – we also lost quite a bit of building science along the way. This government places a great deal of emphasis on insulation and expensive heat pumps for the decarbonisation of our homes and almost nothing on another important factor in saving energy: the airtightness of our buildings.
This reflects both a lack of confidence from within Whitehall in the quality and accuracy of UK construction, and perhaps also a suspicion of mechanical ventilation and heat recovery (MVHR) systems, which transfer around 90 per cent of heat from a building’s stale expelled waste air into the fresh filtered air that is sucked inside. MVHR systems can be relatively cheap, they’re highly conducive to good human health and they’re usually used in Passivhaus houses. It is a mark of the construction process that these homes don’t usually need any heating at all, just the MVHR system, which uses a meagre amount of electricity.
Looking at this another way, the current government strategy laughably swaps one form
