Triskele Energy Assessors – SAP and EPC made easy

Triskele logo

E-mail:         Telephone: 07963 936 735

New Regulations

New energy efficiency regulations are due to come into force in 2022.

England - Part L1A 2021

Part L1A 2021 will be implemented in June 2022 and will see a 31% reduction in CO2 emissions compared to the current standard (Part L1A 2013). A new Primary Energy target has also been introduced, sitting alongside the more familiar Carbon Emissions (DER vs TER) and Fabric Energy Efficiency Standard (DFEE vs TFEE).


As part of the changes, the Standard Assessment Procedure (SAP) has been updated and under the revised regulations, new-build dwellings will be assessed using SAP 10 methodology.


The 2022 changes are viewed as a stepping stone towards a more challenging target that will be coming into force in 2025. The Future Homes Standard will bring significant changes to energy efficiency regulations in the domestic housing sector with a 75-80% reduction in CO2 emissions compared with the 2013 targets.

How much tougher will it be to pass?

Stepping stone or not, Part L1A 2021 represents a significant uplift on the current standard. To provide some context, it is helpful to look at the specification that will be used to set the Target Emission Rate (TER). Standards have been raised across a range of areas but there are some key features that stand out:


  • Wall U-value of 0.18 W/m²K
  • Window U-value of 1.2 W/m²K
  • Wastewater heat recovery for all showers
  • Photovoltaic (PV) system


The above points give an indication about the level of uplift that will be required in order to meet the new targets. However, it is important to note that these features are not necessarily required if the same level of improvement to overall performance can be met in other ways.

Transitional Arrangements – Important note

Transitional arrangements apply to individual buildings, not whole sites as for previous regulations changes. In order to build to current regs (Part L 2013), developers will need to:


  1. Submit a building / initial notice or deposited plans by June 2022; and
  2. Commence work on each individual building by June 2023.


If these criteria are not met for any building then that building will need to comply with the new standards.


Definitions of commencement as follows:


  • Excavation for strip or trench foundations or for pad footings
  • Digging out and preparation of ground for raft foundations
  • Vibrofloatation (stone columns) piling, boring for piles or pile driving
  • Drainage work specific to the building(s) concerned

Changes in the other nations


There are a few differences to the Welsh Part L proposals. There will be a 37% uplift over the preceding standard (Part L 2014) and, in the absence of FEES targets, minimum requirements for thermal elements are stricter than in England. External walls of houses, for example, will need to meet an area weighted average target of 0.18 W/m²K. Primary Energy targets will also be introduced and new build houses will need to achieve a minimum B rating on the EPC.


In Wales the new Part L is expected to come into effect in the Summer of 2022.


The consultation on changes to Section 6 closed on the 28th of November 2021. The new standards are expected to be published in early 2022 and due to come into effect in mid-2022. Two options are on the table for carbon emissions reduction over the current regulations with proposals for a 32% uplift being explored alongside a more challenging 57% option.


A further step-up in the energy efficiency regulations are expected in 2024.

Northern Ireland

Northern Ireland’s consultation on changes to Part F is due to close on the 19th of December 2021. Two options for domestic buildings are currently being discussed: a 25% uplift over currents regs vs 40% (with 25% for flats). Publication of the revised Technical Booklets is expected in 2022 with implementation shortly afterward.


Northern Ireland still applies SAP 2009 methodology and will continue to do so for the time being however, future changes are in the pipeline that will upgrade to SAP 10.

What else should I know about the new regulations?

SAP 10 and the regulations documents have yet to be confirmed. Beta SAP software has been based on consultation documents but it is expected that the final versions will not be significantly different from those that are currently available.


Accredited Construction Details (ACDs) will no longer be valid for thermal bridging calculations. This has the potential to be a significant factor for SAP calculations as the use of default values will certainly be detrimental to performance. Builders using cavity wall construction will be largely insulated from this change as concrete block manufacturers have provided calculated psi values for a wide range of junctions. For other construction methods like steel and timber frame there are very few manufacturers that provide details with psi values. It remains to be seen if more manufacturers will come forward with values or if builders will need bespoke calculations for their own construction specifications – potentially quite a costly exercise.


The regulations will also be changing for upgrades to existing dwellings that come under Part L. There are improved U-value requirements for new or replacement thermal elements along with new Primary Energy and FEES targets. Non-Domestic dwellings too, will see changes, with reduced carbon emissions and the introduction of additional targets.