SAP Calculations

Helping you evaluate the energy and environmental performance of your residential property

Simplifying compliance with Part L Building Regulations

Standard Assessment Procedure (SAP) calculations often involve complex data and technical jargon, making them difficult for architects, developers and self-builders to navigate.

At Energy Digest, we simplify SAP by breaking down the details into clear, understandable insights. Our energy consultants will provide you with actionable recommendations to help you make informed decisions with confidence, all while ensuring your build complies with the energy efficiency requirements of current building regulations, as set out in Part L.

Why do you need this service?

Regulatory
compliance

Whether you’re working on a new build, conversion or extension, SAP calculations are required at the design and as-built stage of the construction process to demonstrate compliance with Part L.

Energy efficiency
guidance

They help optimise material and system choices, improving your property’s energy performance and reducing operational costs.

Energy Performance
Certificate (EPC)

Once the as-built calculation is complete and compliant, we can issue the valuable EPC certificate.

Our Process

Collect your building information,

gathering architectural plans and system details.

Arrange your initial consultation

to discuss project-specific goals and challenges.

Complete the SAP assessment,

conducting calculations at the design stage.

Review the results

and implement changes to improve energy performance if necessary.

Support throughout construction

to help keep your project on track.

Issue certification

by providing the final EPC to confirm compliance.

Why choose Energy Digest?

Our role is to provide you with accurate SAP calculations, so you have everything you need to complete this element of your project with both speed and ease.
Our process is designed to deliver a detailed review of your materials and systems, which will then be presented in clear documentation ready for Building Control approval. We can also incorporate overheating and water calculations alongside your SAP ratings for 360-degree compliance.


Up to three revisions are included in our SAP calculation service, ensuring we have the flexibility to accommodate your evolving designs. Our holistic approach also means there’s no need to liaise with multiple providers, as we can handle most of your building compliance requirements under one roof.

Fast turnaround time

To help you meet your own deadlines, we’ll ensure your SAP assessment is issued within 7 days.

Multi-disciplined team

We cover 20+ services in the built environment, with specialists providing high-value calculations and strong advice.

Practical solutions

Our professionals provide recommendations that are calculated to ensure real world outcomes, resulting in cost-effectiveness and high impact.

Unrivalled support

Our service doesn’t end with the reports. We can provide ongoing support and expertise, from planning to completion.

Speak to our
experts today

FREQUENTLY ASKED QUESTIONS

SAP Calculations
FAQs

SAP calculations evaluate energy efficiency during the construction phase, while the EPC provides a final energy rating upon project completion.

SAP scores depend on factors like insulation, heating, ventilation, and renewable energy sources. Higher scores (1–100+) reflect better energy efficiency.

Architectural plans, insulation specifications, and details about heating, lighting, and ventilation systems are essential for accurate assessments.

At the design stage to confirm compliance and make sure the build will meet energy efficiency standards before construction begins, and at the as-built stage to verify construction accuracy.

Adjustments like improving insulation or upgrading heating systems can address the failure, followed by a reassessment to confirm compliance.

Yes. They are a must for new builds, but SAP calculations are often required for significant extensions and conversions to ensure compliance and energy efficiency.

HEM is expected to replace SAP calculations in the future, pending smooth progression through consultations and government approval.

Navigating the shift towards
HEM compliance

Regulations are changing. Right now, Standard Assessment Procedure (SAP) calculations are the UK’s official method for evaluating the energy and environmental performance of residential buildings. They are required for all new builds, and in many cases for conversions and extensions, to ensure compliance with Part L Building Regulations.

However, in the near future, the SAP model will be replaced by the Home Energy Model (HEM), which will work in a similar manner but will require more involved calculations. The move is all part of the UK government’s strategy to reduce emissions from all buildings – including residential dwellings – and reaching its longer-term sustainability targets. 

Rest assured, Energy Digest is keeping a close eye on the consultation for the Future Homes Standard, which will dictate when and how the HEM comes into play. For now, SAP calculations are an essential part of bringing together the final EPC at the as-built stage, and we will advise our clients on how the transition to HEM can be managed in due course. 

Spoke with Josh who not only reassured me but asked for a fee that I thought was fair. Thank you Josh. Use again? Definitely.

Steve Quirk

The team really know their stuff – super helpful and always had clear answers to any questions or compliance issues we ran into. Definitely our go-to for any future projects!

Nathan Donnelly

Quick and well priced water calculation service and received an appliance specification report alongside the certificate which was really useful for us and the building control officer, highly recommended!

Ilma Akhtar

Very knowledgeable about building regulations, and the industry. Always goes the extra mile to help out! 5*

Karim Meraga

Still unsure?

We offer free phone call and email support until you’re ready to proceed with us.
Access free support for your project now.

crossmenu