Although the consultation on the 2025 Future Homes Standard is still open, an update from the Government today has shed light on what the industry can expect from the major revision to Building Regulations.
In short, absolutely nothing.
After all the fuss and (mild) panic about what new minimum U-Values could be in 2025, it looks like there won’t be much change after all.
2025 – no change
After months of discussion within the industry, which began in the belief that the new minimum U-Value for windows would drop to just 0.8W/m²K, it appears there is going to be no change at all.
Discussion did begin to shift to 1.0W/m²K or 1.2W/m²K. But before that point, the belief that 0.8W/m²K would be the new standard began a whole new discussion around triple glazing being the only way to comply. Indeed, systems companies such as Eurocell, Deceuninck and Liniar have all spent lots of time and money developing new systems, centred around triple glazing, design to get to 0.8W/m²K.
Despite the haste to bring new systems to market, it now appears that there was no such pressing need in the end. These are the two key paragraphs for the fenestration sector which appear to have killed the idea of lower U-Values:
The performance requirements in this consultation closely resemble the fabric standards in the 2021 Part L uplift to the Building Regulations. We investigated including better walls, floors, roofs, triple glazing and improved thermal bridging. However, the only cost effective and practical improvement we found could be made to the standard was an improvement in airtightness. This improvement in airtightness is matched with the change to a decentralised mechanical extract ventilation system, in line with Approved Document F, Volume 1: Dwellings.
The decision to keep fabric standards largely the same is driven by several factors. Firstly, the level set in 2021 will ensure that (with adequate ventilation) new homes do not generally experience damp and mould or excessive temperatures; an increase in fabric beyond this level does not give significant additional benefit. Secondly, it allows efficient low carbon heating, including modern heat pumps, to function well. The move to low carbon heating is central to the government’s commitments to decarbonise housing, and so fabric must be set at a level that allows these systems to work efficiently. Again, increasing fabric beyond the proposed level does not deliver significant gains to the efficiency of heating systems. Thirdly, because the electricity grid is decarbonising rapidly, and the efficiency of heat pumps significantly reduces energy demand, further reducing total energy use is relatively less important than switching to electric sources of heat in efforts to decarbonise. Grid decarbonisation also means that fabric improvements are increasingly not a cost-effective intervention to reduce carbon. This means that as we increase fabric beyond the proposed level, the monetary value of carbon saved by increasing fabric efficiency is less than the cost of installing that additional fabric. As such, there are other interventions that decrease carbon and consumer bills in a more cost-effective way, such as (above) switching heat source and including solar PV panels.
You can read the entire update here: https://www.gov.uk/government/consultations/the-future-homes-and-buildings-standards-2023-consultation/the-future-homes-and-buildings-standards-2023-consultation#performance-requirements-for-new-buildings
So from 0.8, 1.0 and 1.2W/m²K the Government now appears to be saying that there will be no major changes at all. This follows on from a statement PM Rishi Sunak made where he intimated that there would be no more changes to homes that would cause further costs for homeowners.
What it means
The reality for the fenestration sector is that there will now be no new reality after all. Not so long ago we were anticipating the industry having to embrace triple glazing in a much bigger way to be able to comply with the new regulations. Fabricators had meetings about it, there is even another Triple Glazing Question planned – although if it still does go ahead there will be far less urgency and impact as there perhaps would have been had the Government chosen to reduce minimum U-Values.
It also means that the new PVCu and aluminium systems that were developed to meet 0.8W/m²K are not going to be as pivotal. Although I will argue that our industry does need to continue to develop and new more energy-efficient systems to give homeowners a choice and demonstrate that our sector in itself can be greener and proactive when it comes to helping to reduce energy bills and our carbon footprint.
For those arguing against triple glazing, this is a win. There was a significant proportion of installers and fabricators voicing their displeasure at the thought of moving heavily towards triple glazing, with concerns over cost, weight, health and safety and hardware. For those who stood to benefit from triple glazing, namely spacer bar manufacturers and glass makers, this will be a loss. Had lower minimum U-Values forced the sector to go heavy on triple glazing it would have meant a significant increase in sales of glass and spacer bars.
Looking at this from a personal perspective, I do see this as an opportunity lost. If you read the reasoning behind the Government’s explanation why they chose not to change the requirements around the fabric of the building, they are pretty weak. We know how much of an impact highly energy-efficient windows and doors make to the overall performance of a home. Having windows move down to 0.8W/m²K or even 1.0W/m²K would have made a difference. My only reservation was the sector moving towards triple glazing as the method of compliance when I believe we should have been looking at and expanding other technologies such as VIG which would have consumed fewer materials and achieved excellent energy efficiency.
As is it, all the hype and discussion will remain just that. This is a big dose of cold water for the entire U-Value debate and the industry can probably stand down and switch it’s focus on to other issues.
The Government consultation on FHS continues and runs until 6th March 2024 – new updates/information will be published on DGB.
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