Upcoming Changes in UK Environmental Regulation (2025–2026): What Developers Need to Know

If you work in construction or development, the next 18 months will likely feel quite busy. Policies are nudging projects toward delivering lower operational energy, better fabric, and fuller carbon accounting across the life of a building.

There is also a tightening of expectations on what you evidence at planning and handover.

The direction of travel is clear – net zero, better building performance, and a more consistent approach to waste and materials. England’s new workplace recycling rules even reach construction and site offices, which is a small but somewhat telling sign of how far compliance now extends into day-to-day operations.

The short version of what is changing.

Government plans to publish the Future Homes Standard in autumn 2025, lay the regulations in December 2025, and then bring them into effect from December 2026 with transitional arrangements in place. In practice, this will sit on top of the 2021 uplift to Parts L and F and the introduction of Part O on overheating, so design teams should expect tighter baselines and firmer evidence, not starting from a totally clean slate.

BREEAM is evolving too. From April 2025, Home Quality Mark transitioned into BREEAM UK New Construction: Residential (V6.1), while Version 7 of BREEAM New Construction is rolling out with a heavier emphasis on whole-life carbon and resilience. This matters for planning commitments, funder requirements, and disclosure.

The Future Homes Standard, what it means in practice.

The Future Homes Standard will set the tone for the next wave of residential compliance, tightening up on primary energy and carbon metrics and reshaping how SAP assessments are performed. The Government consultation outputs point to new performance targets, updated modelling, and transitional arrangements so that schemes already in the system are not left stranded having fallen between the gaps.

If you are bringing a scheme forward now, it’s safe to assume you will need early energy strategy, fabric-first choices, and defensible SAP evidence to avoid potential redesigns when the regulations kick in.

enevo can support energy statements, SAP and SBEM modelling, psi-value calculation, and liaison with planning officers where an agreed compliance route needs setting out.

Parts L and O, fabric, thermal bridges, and overheating

Approved Document L still remains the anchor for energy compliance. The 2021 edition, with 2023 amendments, lifted the bar on fabric performance, airtightness testing, and documentary evidence. Authorities now need photographic records and clear audit trails for junction details to demonstrate that design intent made it to site. Pair this with Part O, (which has applied since June 2022), introducing overheating standards for new residential buildings and allowing either a simplified route or dynamic thermal modelling.

For dense urban sites, especially in London, dynamic modelling can often be the safer path to take. enevo’s team can produce SAP and SBEM reports, psi-value libraries, and CIBSE TM59-aligned overheating studies to get you to a compliant design without costly late changes.

Whole-life carbon and embodied impacts are taking the spotlight.

We expect more and more planning files to include a Whole Life-Cycle Carbon Assessment, not just an operational energy statement. In London it is already required for referable schemes under London Plan Policy SI 2, supported by detailed GLA guidance and templates.

Other authorities are clearly watching and borrowing the approach with an emerging pattern becoming quantify A1–A5 and B–C impacts, show design decisions to reduce them, and keep the numbers ‘live’ through to post-construction. Again, enevo can prepare WLCA models, LCA reports, and the accompanying planning text so your submission reads clearly and aligns with the local template.

Testing and in-use performance, sound, air, and ventilation

Pre-completion sound insulation testing under Part E, airtightness testing, and ventilation commissioning under Part F continue as before, but the evidencing requirement around them is narrowing. Authorities and clients are increasingly asking for calibrated test certificates and digital handover packs. If your scheme is targeting BREEAM credits for acoustics or indoor air quality, setting up early coordination between design and site teams is well worth the time. Get in touch if in doubt, we offer sound testing to Part E, ventilation testing to Part F, and air-tightness testing with clear reporting that drops cleanly into O&M files.

BREEAM, HQM and performance accreditation

Since April 2025, residential projects have moved from HQM to BREEAM UK New Construction: Residential V6.1, which adjusted daylight criteria, strengthened embodied carbon measurement, and refreshed certificate formats. More broadly, BREEAM Version 7 raises the profile of whole-life carbon and alignment with EU taxonomy, which you will see reflected in pre-assessments and employer’s requirements. If you need to lock down a planning obligation or a funder’s ESG covenant, appoint a BREEAM AP early and map the credit route to your design programme. (Again, we can provide BREEAM AP and assessor services across New Construction, Refurbishment and Fit-Out, and In-Use).

Fire and smoke control join the environmental story too.

Although primarily a Building Safety domain, design choices for smoke control, compartmentation, and shaft layouts also affect energy use, apertures, and overheating risk.

Since 2021, many planning authorities required fire statements alongside energy and daylight material, (especially in London). CFD modelling is widely used to test smoke control strategies before you commit to plant sizes that could compromise façade performance. For complex projects, seek expert engagement and support to help integrate CFD studies with energy and overheating models so you avoid conflicts later.

What next?

With all these regulatory strands in mind, the question is how best to prepare. A few practical steps can help:

• Carry out an early compliance review – map Future Homes Standard requirements against current designs, (even if the regulations are not yet live).
• Nail down your energy and overheating strategy – choose your SAP/SBEM route, model thermal bridges, and decide whether simplified or dynamic overheating assessments are required.
• Plan for whole-life carbon – scope whether your project will need a WLCA and agree methodology before design sign off/freeze.
• Set your BREEAM pathway – look to appoint a BREEAM AP early, agree credit priorities and integrate them into the programme.
• Get testing agreed – get build sound, air-tightness, and ventilation testing into procurement and site logistics processes, and prepare to deliver digital certificates.
• Keep records from day one – things like photographs of junctions, commissioning plans, calibrated test reports. Evidence matters – treat them as ‘compliance currency’.
• Budget realistically – budgets are always tight, but proper LCA modelling, additional testing, and AP time all carry costs, but are ultimately far cheaper than redesigns or delayed approvals.

If you would like a quick sense-check on a planned or live scheme, get in touch with enevo Building Compliance team. Send us your drawings and planning status and we can help scope the SAP or SBEM work, outline a WLCA plan, map a BREEAM route, and advise on testing to help you move through coming months with fewer surprises.