Consultation on the Future Homes Standard closed at the end of March so what do fabricators and installers need to know? Greg Tabberer, product and technical manager at Deceuninck explains.

Consultation closed on the Future Homes and Building Standard on the 27 March. After the level of expectation that had been placed on it in the run up to publication, the end of the consultation period received very little public note.

It is, however, significant. “This is less because of recommendations for expected U-values for new build windows of 1.2 W/m²K – a far more comfortable target than the 0.8 W/m²K that had been expected,” explains Greg Tabberer, product and technical manager for Deceuninck.

“More because of fundamental changes to the model for measuring building performance and the move to the new Home Energy Model and away from the pre-existing SAP rating, which has some very substantial implications for window and door companies.”

What is the Future Homes Standard?

The Future Homes Standard, renamed the Future Homes and Buildings Standard in December 2021, will complement the Building Regulations to ensure new homes built from 2025 produce 75-80% less carbon emissions than homes delivered under the old regulations.

What is the Home Energy Model?

The Home Energy Model has been created from a three-year research project between the Department for Energy Security & Net Zero (DESNZ), and the Building Research Establishment (BRE).

It will be used to set standards for new homes to ensure that they will be ‘zero carbon ready’, future-proofed with low carbon heating and world-leading levels of energy efficiency.

If the recommendations made in the consultation are followed, it will become the new methodology used to demonstrate that new homes meet targets under the Future Homes Standard.

The government has also signalled its intention to use the Home Energy Model to determine assessments for EPCs.

“It means that from next year [2025] the Home Energy Model is likely to replace the Standard Assessment Procedure (SAP) for energy ratings of homes, something which is used to evidence compliance with building regs but also used to generate Energy Performance Certificates,” explains Greg.

“More generally, we’re also seeing a shift in government calculations away from a fabric first approach to bring increased focus to how homes are heated, and the energy used to do it, including a far more detailed assessment of green technologies including heat pumps.

“That goes some way to explaining what the downgrading of the requirement for windows from the 0.8 W/m²K that much of the industry had expected, to the 1.2 W/m²K, which we saw published in the consultation.”

Greg, however, warns that if you thought that you could breathe a sigh of relief at the recommendation in the consultation that the standard for new windows should be set at 1.2 W/m²K, you should probably think again.

“The caveat is that we still don’t know that the government will move forward with the Home Energy Model, but the reality is that it is likely,” continues Greg.

“It’s based on the belief that you get out, what you put in, and for windows and doors it is unlikely that standard sizes will cut it.”

“The proposal instead is to use ‘either the actual size and configuration of the window or door, or measured using the appropriate hot box method set out in the BS EN ISO 12567 series’.

“This effectively means modelling each specific window configuration – and that creates a challenge because most of windows supplied in a real-world context are smaller than the ‘standard’ window configuration (1,230mm x 1,480mm open/fixed).

“The smaller the glazed area, the harder it is to achieve a u-value of 1.2 W/m²K. This is especially problematic where steel reinforcements are required.”

This is also likely to place a new requirement on fabricators and software companies to be able to evidence modelling and compliance to exact window dimensions.

“These are achievable things,” continues Greg, “but the industry is going to have to move relatively quickly to be ready for 2025 and beyond.”

When will the new guidance be released?

The Government’s plan is to release the updated regulations and relevant guidance this year, with standards set to take effect starting in 2025.

“While right now the focus is new build, it’s worth remembering that the definition of new build in building regulations includes home extensions, so even if you’re in the home improvement space, it is likely to impact your business,” says Greg.

“Longer term, and given the importance of retrofitting homes in tackling climate change and reducing emissions, it is likely that the Home Energy Model will be extended into replacements.