On March 24th, the UK Government published its response to the Future Homes and Buildings Standards consultation. For housebuilders, the message is clear. You've got 12 months to get your projects through Building Control, or you're building to a completely different, more costly standard.
The new regulations come into force on 24th March 2027. Any Building Control application submitted after that date will need to comply with standards that effectively rule out fossil fuel heating, require solar panels on most new homes, and demand significantly better fabric performance than we’re seeing today.
It’s a major shift. And while the government has provided transitional arrangements i.e. applications submitted before the deadline can proceed under current 2021 standards for another year, the window for taking advantage of them is closing fast.
What’s Changing
The changes focus on building more energy efficient and sustainable homes, achieving 75% lower emissions than those built in 2013, making low-carbon heating, on-site renewable generation, and improved insulation the new baseline.
Heat Pumps
The Future Homes Standard sets the notional building specification around an air source heat pump, making gas boilers commercially unviable for new builds. That alone changes everything about how heating systems are designed, sized, and installed.
Solar Panels
The government has introduced a new legal requirement for renewable electricity generation, mandating solar PV equivalent to 40% of each dwelling’s ground floor area. There’s some design flexibility built in (dormer windows and roof valleys won’t kill your compliance), but it needs to be planned from the start, not retrofitted into designs later.
Building Fabrication
Fabric standards are tightening too. Whilst wall U-values remain the same as Part L 2021, glazing specification details are changing. Currently, the notional uses a g-value of 0.63 and frame factor of 30%. If a site has a low g-value, the SAP results are penalised due to the reduced levels of solar gains.
Under FHS, both the g-value and frame factor are being uncoupled from the notional, which means SAP reports won’t fail on account of having low g-values. Hitting the required air permeability score will be more challenging as the target is reducing to 4.0 (It was previously 5.0).
These changes to Part L are a fundamental redesign of how new homes are specified. Heat pumps change your electrical infrastructure, your hot water strategy, your plant room requirements. Solar affects your roof design and grid connections.
These aren’t last-minute adjustments or things that can be considered retrospectively, they need to be baked into the design from day one, and will inevitably incur additional costs to the housebuilder.
Increased Costs For Housebuilders
The government estimates a cost increase of £4,350 per dwelling. That’s driven by heat pump installations, solar panel requirements, better insulation, and the additional design work needed to prove compliance.
And that’s before you factor in the operational challenges. Heat pump installers are already stretched. Grid connection queues are growing. Supply chains for enhanced insulation and high-performance glazing will face increased demand. The longer housebuilders wait, the harder and more expensive it gets.
The Clock is Ticking
Any Building Control application submitted before 24th March 2027 can proceed under the current 2021 Part L standards, as long as construction starts within 12 months of that date.
For large sites with multiple plots, this applies building-by-building. Developers can phase applications strategically, getting as many units as possible locked into 2021 standards before the deadline hits. This transition will also capture any unstarted buildings from the older 2013 version of Part L those plots will need to be uplifted to the new standard too.
Tom Chapman, Business Development Manager for Lucion Survey Ltd, commented:
“We’re already seeing developers accelerate their pre-commencement work. The transitional arrangements are generous if you act now. But once March 2027 passes, housebuilders are designing to a completely different standard with longer lead times, higher costs, and more complex supply chain management. Moving planned developments along faster could save housebuilders thousands in project costs.”
For developments that don’t fall into the transition period who will be designing to the Future Homes Standard from the outset, these projects require a level of preparation many housebuilders aren’t ready for.
The Home Energy Model (HEM), which replaces the Standard Assessment Procedure (SAP), won’t even be available as an approved methodology until at least June 2026, and the government expects a 24-month “dual running” period with SAP 10.3 before HEM becomes mandatory. These methodologies are the foundation to evidencing compliance with the Future Homes Standard. That’s a lot of uncertainty to navigate while trying to maintain delivery schedules.
Accelerating Current Developments
The challenge with accelerating projects to meet the deadline is that you can’t cut corners on technical due diligence. Poor survey data or delayed assessments create a cascade of problems that can push you past critical dates.
A topographical survey that misses key site constraints means design revisions. A utility survey that fails to identify services means on-site delays when you hit construction. Ecological surveys that aren’t coordinated with your drainage strategy mean weeks of back-and-forth between consultants.
Chapman, who is a housebuilder sector specialist, goes on to say:
“The projects that stall are almost always the ones where technical work happens in silos. Your ecologist finds protected species, which affects your site layout, which impacts your drainage design, which changes your levels.
Suddenly, you’re three months behind and your Building Control submission date has slipped past the transitional deadline.”
This is where Lucion Survey’s integrated approach makes a difference. As part of the Lucion Group, we coordinate the full range of technical assessments housebuilders need. From topographical surveys, PAS128 utility detection, supported by our in-house CAD technicians, to ecological assessments, ground investigations, flood risk, arboricultural surveys, Biodiversity Net Gain, our team remove the gaps between multiple suppliers.
When your survey data, ecological constraints, and drainage strategy are being managed holistically, issues get flagged and resolved faster. That’s the difference between meeting your Building Control deadline and watching it slip away.
The Bottom Line
Regardless of which route housebuilders take, to accelerate current projects or lean into the new requirements, technical accuracy and environmental considerations are essential to securing planning.
Lucion Survey Ltd is a CHAS Elite accredited specialist land and building surveying company. With in-house CAD technicians and national presence, our team deliver topographic, cut and fill, and utility and drainage surveys for housing developments.
Speak to Tom and our team at Lucion and mitigate delays and extra cost: [email protected]
