Meeting Part L and the Future Homes Standard

For architects and specifiers, meeting Part L means coordinating the building fabric, heating, ventilation and energy strategy from the earliest design stages.

Heat pumps have an important role in that strategy. However, selecting an efficient unit is one part of delivering a home that meets the applicable performance requirements and works well for its occupants.

With the Future Homes Standard now finalised, project teams also need to understand the implementation dates and how they affect specifications being developed today.

Updated October 2026. This article focuses on dwellings in England. Wales, Scotland and Northern Ireland have separate regulatory requirements.

How do Part L and the Future Homes Standard relate?

Part L is the part of the Building Regulations concerned with energy performance. Approved Document L provides statutory guidance on ways to meet the relevant requirements.

The Future Homes Standard is being implemented through changes to those regulations and associated guidance. It is part of the wider Future Homes and Buildings Standards, which also cover non-domestic buildings.

For new homes in England, the direction is towards energy-efficient buildings with low carbon heating. The Government describes these homes as “zero carbon ready”, meaning they should not need further heating retrofit to become zero carbon in use as the electricity grid fully decarbonises.

This concerns operational performance. It should not be presented as a guarantee of zero whole-life carbon, which also involves construction materials and other impacts.

Which requirements apply to your project?

The 2026 edition of Approved Document L was published on 24 March 2026. The main regulatory changes take effect from 24 March 2027, with different timing for higher-risk building work and transitional provisions.

Under the Government’s transitional arrangements, qualifying non-higher-risk projects can remain subject to the previous requirements where a building notice, initial notice or full plans application is submitted before 24 March 2027 and work commences on the relevant building before 24 March 2028.

A site-wide programme should not be assumed to protect every building under earlier standards. The definitions of commencement and the conditions attached to the transition matter.

Confirm the applicable requirements with the building control body and energy assessor before fixing the specification.

Assess the whole dwelling

New dwelling compliance considers the performance of the proposed home against a theoretical “notional dwelling” with standardised fabric and services.

The assessment includes targets for emissions, primary energy and fabric energy efficiency. Minimum standards for individual elements and services also need attention.

This means a heat pump’s efficiency cannot be assessed in isolation from insulation, glazing, airtightness, ventilation and hot water provision.

The energy assessor should work to the regulatory edition applicable to the project. Where earlier requirements apply, the corresponding Approved Document L guidance should inform the assessment.

Bring the assessor into the design process early enough to test the proposed combination of fabric and services. Discovering a shortfall after equipment has been ordered leaves fewer options for resolving it.

Understand the role of heat pumps

The Future Homes Standard is expected to deliver new homes with, on average, at least 75% lower carbon emissions than homes built to the 2013 standards.

Low carbon heating, including heat pumps, is central to this approach. Suitable heat network connections can also form part of a project’s strategy. questions-statements.parliament.uk

The Government retains a performance-based approach, so the appropriate solution should be assessed against the actual dwelling and applicable requirements. A product should not be described as automatically delivering Part L compliance.

For a heat pump specification, provide the assessor with the selected model’s relevant performance information, proposed heating flow temperature, hot water arrangement and controls.

Keep compliance modelling and heating design coordinated. The dwelling’s energy assessment does not replace a room-by-room heat-loss calculation or detailed equipment selection.

Design the heating system for efficient operation

Heat pumps can operate more efficiently at lower heating flow temperatures, provided the emitters can deliver the required heat.

This makes early coordination of radiators, underfloor heating and room layouts valuable. A room-by-room heat-loss assessment establishes the demand in each space, allowing the heating designer to check emitter outputs at the intended operating temperatures.

Reserve space for the cylinder and associated equipment, coordinate pipe routes and agree the control strategy. Outdoor unit positioning should also accommodate airflow, acoustics and maintenance access.

These decisions help turn the performance assumed during design into a system that can be installed and commissioned as intended.

Plan renewable electricity alongside heating

The 2026 changes introduce Requirement L3 for on-site renewable electricity generation when new dwellings, or buildings containing dwellings, are erected, subject to the applicable exceptions.

Solar PV will be a common way to meet this requirement, but the guidance addresses renewable electricity output and allows other renewable technologies.

The generation strategy needs to account for site demand, available infrastructure and design constraints, including the capacity of the electricity connection and any export limits.

For architects, the practical implication is to consider roof geometry, shading, plant locations and electrical provision together. Coordinate the solar and heat pump strategies while the building design can still accommodate both.

Annual renewable generation should not be interpreted as a guarantee that solar panels will directly cover the home’s heating demand throughout winter.

Use the appropriate compliance methodology

In its Future Homes and Buildings Standards consultation response, the Government confirmed SAP 10.3 would be available at launch, with the Home Energy Model intended to become an alternative approved methodology before a future transition to HEM alone.

Agree the approved methodology and software version applicable to your project with the energy assessor. Keep the assessment updated when fabric specifications, equipment or controls change.

A proposed substitution should be reviewed for its effect on both the heating design and the compliance calculations.

Protect performance through installation and handover

Design-stage calculations depend on what is ultimately built and installed.

Set clear responsibilities for recording construction details, reviewing substitutions, testing and commissioning services, and supplying the information required for the completed dwelling.

For the heating system, ask for commissioning records, control settings and clear operating and maintenance instructions. Homeowners need guidance that relates to their actual equipment and explains how to use it efficiently.

The 2026 changes place further emphasis on homeowner information and the Home User Guide. Include these deliverables in the project programme.

What about renovations and extensions?

Part L also applies to relevant work on existing homes, including aspects of extensions, replacement elements and building services.

However, a renovation should not automatically be treated as though the entire property must meet the new-build Future Homes Standard.

The applicable provisions depend on the work being undertaken, the building and the relevant regulatory edition. Agree the scope with building control and the project’s advisers before setting performance targets.

For heat pump projects, use the opportunity to coordinate any planned fabric improvements with the heating design.

Discuss your project with KronoHP

A coordinated specification brings together the regulatory assessment, building design and heating system requirements.

As the UK distributor of Kronoterm heat pumps, KronoHP can discuss the range and the product information needed to support equipment selection.

Share your plans, heat-loss calculations, proposed flow temperatures and hot water requirements with our team to explore suitable heat pump options for your project, alongside your heating designer and energy assessor.