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James Parker calls for a dramatic response from construction to climate change

A survey of housebuilders a few weeks back produced what might be a surprising finding around the methods they are choosing for Part L compliance, namely that air source heat pumps are a very big favourite for helping builds cut the 31% from new builds’ emissions.

There have been a wide range of views (as on every subject these days), from 31% not being a major issue (e.g. because the London Plan already demands a whopping 35% reduction beyond Part L), to it creating a host of problems, including on the heat pump front.

Issues such as recruiting the necessary number of installers to satisfy demand before the Future Homes Standard in 2025, and enough savvy professionals to maintain this new style of heating at scale across the UK remain a headache.

The construction response to climate change needs to be on the same footing as a pandemic, whatever the upfront cost

James Parker James Parker Editor of Architects DataFile

Underlying costs

The Private Housing Construction Cost Index produced by the Royal Institute of Chartered Surveyors’ Building Cost Information Service (BCIS) is based on housebuilders’ costs for a standard house.

Although it reflects “only the movement in the underlying direct costs,” says BCIS, the recently published index was revealing, and gave the lie to the idea that heat pumps’ time would be the Future Homes Standard and not now, with fabric improvements able to carry the can for Part L.

However, 45% of respondents to the BCIS survey said air source heat pumps were their chosen solution to meet requirements of Part L, whereas 30% selected gas boilers and PV.

The remaining respondents said their preference would be a combination of heat pumps and gas for their developments.

BCIS said only a “limited number of respondents” said their preference in meeting Part L emissions was for a combination of gas boilers and PV, extra wall and floor insulation, and mechanical ventilation with heat recovery (MVHR).

Part L cost uplift

The estimated cost uplift for meeting Part L Building Regulations, as reported by housebuilders in the fourth quarter of 2022, stands at 3.6%.

The likely overall cost increases per home built were flagged by a leading commenter in the housebuilding industry, Chris Carr, at our recent round table, Building Insights LIVE: ‘Solutions for Compliance – Part L and beyond.’

Chris is the vice president of the Federation of Housebuilders, as well as running his own housebuilding company in Grimsby, so he knows what he is talking about.

Worryingly, he believes that the cost uplift per home is a lot higher than 3.6% for him, although he operates in probably a more high-end set of parameters than most builders.

Pushing back the deadline?

The heat pump industry is frantically training installers and maintenance professionals to ensure that it can satisfy demand (currently we are building around 180,000 homes per year but this needs to increase).

However, Chris Carr for one is not convinced that all of the multifarious solutions to the Future Homes Standard will be in place for housebuilders by 2025, which comes down in many cases to a high-wire act between the regs on performance, those on overheating, and the necessary focus on ventilation.

He is advocating for a pushing back of the deadline, even though this will be dismal news for climate change warriors – and I doubt he is the only one.

Air to air heat pumps

As we approach Clean Air Day on 15 June, it’s also worth reiterating that specified correctly, air to air heat pumps can not only deliver heating and cooling to homes, they can also function extremely well as air purifiers.

As Part L brings even tighter buildings, with fewer air changes if unmitigated, such systems, by constantly circulating air, can offer a reliable long-term solution for the indoor air quality vital to a healthy life.

It would be interesting to know how the take-up of those particular systems is being incentivised in the UK, if at all.

A catastrophic failure

As the BCIS survey bears out, housebuilders will be installing heat pumps, but they must go into fabric-enhanced buildings.

If we don’t this could be one of the most catastrophic failures, nationally, that we have ever seen in the industry.

It’s time for Government to genuinely take the lead and fork out for the improvements, in the same way they did on furlough, otherwise housebuilders will do what their particular consultants tell them to do in order to pass regs, and this may not be a holistic solution.

Basically, the Government needs to put the construction response to climate change on the same footing as a pandemic, whatever the upfront cost.

James Parker is editor of Architects DataFile and Housebuilder & Developer