The way new homes are designed and assessed for energy efficiency is about to change significantly. The Government has now published the final Future Homes Standard, introducing a new 2026 edition of Approved Document L together with associated changes to the Building Regulations.
The new standard comes into force in England on 24 March 2027 and represents the next major step towards lower-carbon, more energy-efficient new homes. GOV.UK
For developers, architects and housebuilders, this means that energy strategy will need to be considered much earlier in the design process. Heating systems, solar PV, building fabric, glazing, ventilation and the overall form and orientation of a dwelling will all contribute towards achieving compliance.
What is the Future Homes Standard?
The Future Homes Standard is the new energy performance standard for new dwellings in England. It is being introduced primarily through the 2026 edition of Approved Document L – Energy and greenhouse gas emissions – alongside an updated Approved Document F covering ventilation.
The intention is that new homes are constructed with high levels of energy efficiency and low-carbon heating, so they should not require significant energy-efficiency retrofit work as the electricity grid continues to decarbonise.
One of the biggest practical changes is the move away from designing new homes around gas boilers. The Government has confirmed that gas boilers will not achieve the required performance standard, with technologies such as heat pumps and low-carbon heat networks expected to become the principal means of heating new homes. Solar photovoltaic panels will also become a feature of the majority of new homes. GOV.UK
It is not simply about lower U-values
It would be easy to assume that the Future Homes Standard means substantially lower maximum U-values for every element of the building fabric. In reality, the changes are more nuanced.
The performance of a new dwelling continues to be assessed against a theoretical ‘notional dwelling’ of the same size and shape. The actual dwelling must demonstrate compliance against defined targets for primary energy, carbon emissions and fabric energy efficiency. GOV.UK Assets
This means compliance needs to be considered as a complete energy strategy rather than simply checking individual insulation values.
A well-designed building fabric remains extremely important, but heating efficiency, renewable electricity generation, glazing, thermal bridging, airtightness, ventilation and building services can all influence the final calculation.
Heat pumps and low-carbon heating
One of the most visible changes for new-build housing will be the move towards low-carbon heating.
For many conventional new homes, an air source heat pump is likely to become the natural starting point. Heat pumps operate differently from traditional gas boilers and generally work most effectively with lower heating flow temperatures.
This makes early coordination important. Heating demand, emitter sizes, hot-water storage and plant locations should ideally be considered alongside the architectural design rather than being treated as an engineering exercise towards the end of a project.
Solar PV will become increasingly important
Solar photovoltaic panels will also play a much greater role under the new regulations.
Government policy is that solar panels should be included on the majority of new homes, while Approved Document L contains requirements relating to appropriately sized on-site electricity generation systems, their controls and commissioning. GOV.UK
This makes roof design increasingly relevant to Building Regulations compliance. Roof orientation, available roof area, shading, rooflights and other equipment can all affect the amount of usable space available for PV.
For larger residential developments in particular, these considerations are best addressed while house types and site layouts are still being developed.
SAP calculations remain important
Despite the development of the new Home Energy Model, the Government has delayed its introduction. SAP 10.3 will therefore initially be the approved calculation methodology used to demonstrate compliance with the Future Homes Standard for new dwellings. GOV.UK
SAP calculations will continue to compare the proposed dwelling against its regulatory targets at both design and completion stages.
This makes early-stage SAP assessment particularly valuable. Carrying out the calculation once the construction drawings and specification are effectively complete can result in expensive changes if the dwelling does not comply.
An early assessment allows the design team to understand the effect of different insulation levels, glazing specifications, heating systems, PV provision and other measures before the design becomes fixed.
What about projects already in the pipeline?
There are transitional arrangements for developments already progressing when the new requirements come into force.
For most non-higher-risk building work, the new standards take effect on 24 March 2027. Where the relevant Building Regulations documents have been submitted before that date, the previous Part L requirements can continue to apply provided construction of the relevant building starts before 24 March 2028. Different arrangements apply to higher-risk buildings. GOV.UK Assets
This is particularly important for larger housing developments because the transitional requirements need to be considered on a building-by-building basis rather than simply assuming that an entire site will automatically remain under the previous standard.
What does this mean for developers?
The Future Homes Standard makes early energy assessment more important than ever.
Rather than designing a dwelling and then asking whether it passes Part L, the energy strategy should increasingly form part of the design process itself. Decisions about house orientation, glazing, insulation, heating, ventilation and solar PV can all have implications for compliance, construction cost and ultimately the performance of the completed home.
For developers working on schemes that may cross the March 2027 implementation date, it is also worth establishing now which version of Part L is likely to apply.
How Blackrock Architecture can help
At Blackrock Architecture, we can incorporate energy performance into the design process from an early stage, helping to identify potential compliance issues before they become costly construction-stage problems.
Our in-house services include SAP calculations for new-build dwellings, together with EPCs and associated Building Regulations energy assessments. By combining the architectural design and energy assessment process, specifications can be reviewed and adjusted as the design develops rather than treating SAP compliance as a separate exercise at the end of the project.
If you are planning a new dwelling or residential development that may fall under the Future Homes Standard, please contact Blackrock Architecture to discuss the project and the energy assessments required.
