Future Homes Standard mandates solar on every new home from 2027

The Future Homes Standard, published as the Part L 2026 update to England’s Building Regulations on 13 March 2026, takes effect on 24 March 2027. From that date, every new home in England needs solar PV equivalent to 40% of the dwelling’s ground-floor area and a heating system that meets a tight carbon cap. In practice that means solar and battery storage paired with a heat pump on almost every new build coming out of the ground.

It is the biggest change to new build standards in over a decade. Gas boilers, the default in English new build housing for a generation, will not get a typical home under the new carbon ceiling.

What Part L 2026 actually says

The Future Homes Standard sits inside Approved Document L Volume 1 (dwellings) and replaces the 2021 uplift. The headline metrics are a minimum 75% cut in regulated carbon emissions versus the 2013 standard, and a fixed solar requirement: PV capacity equivalent to 40% of the dwelling’s ground-floor area, applied to each new home individually. Where shading, orientation, or roof geometry makes the full 40% impractical, the rules allow a documented “reasonable amount” instead, but the carbon cap still has to be met by some other route.

Compliance is demonstrated through the new Home Energy Model (HEM), which replaces SAP for new build assessments. During the transition both HEM and SAP 10.3 are accepted, with HEM becoming the sole calculation method later in the cycle. The structure is a carbon-emission target rather than prescriptive technology, but as the Savills explainer of Part L 2026 notes, the cap is tight enough that heat pumps become the default low-carbon heating choice in nearly every dwelling.

How it compares to today’s building regs

The current rules (the 2021 uplift to Part L) cut carbon by around 31% versus 2013 and stop short of mandating solar or heat pumps. Part L 2026 closes both gaps.

Battery storage is not directly mandated, but the maths drives developers towards it. A typical new home will produce more daytime solar than it can use, and adding storage smooths the export-import mismatch while improving the carbon score on the compliance calculation.

The transition window

Part L 2026 comes into force on 24 March 2027, but the regulation includes a 12-month transitional provision. As the Construction Management report on the Future Homes Standard launch details, plots that secured initial notice or full plans approval under the 2021 regulations before that date can complete to the old standard, provided work starts within 12 months. The transition closes on 24 March 2028.

In practical terms, that means three overlapping streams of new build through 2027 and most of 2028:

• Pre-permission sites still being designed: must be built to Part L 2026.
• Sites with planning lodged before March 2027: can use the old regs if construction starts by March 2028.
• Sites already on-site: complete under the regulations that applied when permission was granted.

For anyone buying off-plan, the developer should be able to tell you which set of regulations the plot was approved under. If the answer is the old regs and completion is late 2027 or beyond, it’s worth asking what voluntary PV or heat pump spec is included.

What this means for existing homes

The Future Homes Standard does not require any retrofit on existing housing. Older homes stay under the regulations they were built under, and there is no obligation to add solar or replace a gas boiler. What changes is the market context.

By the early 2030s the bulk of new build stock will arrive with PV, a heat pump, and often a battery as standard. That shifts the bar on what a well-specified older home needs to look like at sale: a recent EPC C or better, a heat pump or a clear retrofit pathway, and increasingly, an existing PV array. Homeowners thinking about how many solar panels their home needs or weighing up heat pump versus gas boiler economics are already moving in the direction the regulations will set as standard for new build.

Cost helps. The 0% VAT rate on energy-saving materials (solar, batteries, heat pumps, insulation) runs to 31 March 2027 under current HM Treasury policy. See gov.uk’s guidance on VAT for energy-saving materials for the current scope, and our overview of the main UK home energy grants for 2026 for what stacks alongside it.

One important geographic caveat

Building Regulations are devolved. The Future Homes Standard only applies in England. Scotland already operates a separate New Build Heat Standard (in force since April 2024) that bans direct-emission heating in new homes, so the destination is similar even if the route differs. Wales is consulting on its own equivalent and is expected to land on comparable carbon targets in 2027 or 2028. Northern Ireland sets its own building regulations and has not yet announced a matching rule. If you are buying or developing outside England, check the regulation that applies in that nation rather than the headline 24 March 2027 date.

The takeaway for homeowners

If you are buying a new build that completes after spring 2028, expect a heat pump, an integrated solar array, and likely a battery as standard kit, without paying for them as upgrades. If you own an existing home, nothing in Part L 2026 obliges you to do anything. But the resale and running-cost gap between a 2028 new build and an unimproved older home is now codified in regulation, which is a useful signal for anyone weighing up when to fit PV, swap to a heat pump, or both.

Last updated: 12 May 2026