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SAP Calculations for Part L Compliance
Professional SAP Calculations for Part L compliance. Fast turnaround and clear, published pricing. Reports for Building Control across the UK.
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TL;DR - SAP Calculations
Design → Model → ComplianceWhat is a SAP calculation?
An energy assessment required for new builds, extensions and conversions to meet Part L Building Regulations.
Who needs SAP calculations?
New builds, extensions over certain sizes, and most dwelling conversions require SAP calculations.
How much do SAP calculations cost?
New builds from £220, extensions from £150. Fixed prices with no hidden extras.
How long do SAP calculations take?
Most projects completed within 2–4 working days once we have your drawings and specifications.
What do you need from me?
Floor plans, elevations, construction details, heating spec and window schedule.
Will Building Control accept your reports?
Yes. All reports completed by Elmhurst accredited OCDEA and accepted by Building Control across the UK.
Ready to get your SAP calculations sorted? Fixed prices, fast turnaround and Building Control approved reports.
What Are SAP Calculations?
SAP Calculations are energy assessments required for new builds, extensions and conversions to demonstrate compliance with Part L Building Regulations. They evaluate a property's thermal performance, energy consumption and carbon emissions to make sure homes meet energy efficiency standards.
The calculation looks at how the property is designed, including insulation, building materials, the heating system and glazing, and predicts how much energy the home will use throughout the year.
The calculation uses SAP 10 methodology to assess thermal performance, including U-values for walls, floors and roofs, air permeability rates, thermal bridging and the building fabric efficiency. This comprehensive energy assessment evaluates carbon emissions and primary energy consumption to determine your property's energy rating.
Your SAP report must be completed by an accredited assessor and submitted to Building Control before construction begins (Design SAP) and once the property is built (As-Built SAP). We provide clear guidance through the whole process and supply reports that are accepted by Building Control across the UK.
Who Needs SAP Calculations?
SAP Calculations are required for most domestic projects in the UK. If you are building a new home, extending an existing one or converting a building into a dwelling, you will need a SAP assessment to show compliance with Part L of the Building Regulations.
New Builds
All new dwellings must have a SAP Calculation before construction begins and again once the property is completed. This confirms that the design meets energy efficiency standards and that the finished home matches the approved specification. View SAP Calculations for New Builds →
Extensions
Many extensions need a SAP Calculation, especially when the glazing area is high or when heat loss needs to be balanced to pass Part L. If your project includes large doors, roof lights or significant glazing, a SAP assessment is often required. View SAP Calculations for Extensions →
Conversions
Converting a building into a dwelling normally requires SAP to show that the new home will meet energy efficiency standards. This includes garage conversions, barn conversions and change of use projects. View SAP Calculations for Conversions →
What's Included in Our SAP Calculations Service
Our SAP service gives you everything you need to meet Part L requirements and keep your project moving without delays. We handle the full process from the design stage through to final approval, with clear guidance at every step, including thermal modelling and energy assessment of your building design.
- SAP Design Stage calculation and thermal modelling
- Full guidance to achieve Part L compliance
- Assessment of U-values, thermal bridging and air permeability
- Unlimited specification revisions
- Clear recommendations to help your design pass SAP
- Carbon emissions and energy rating calculations
- As-Built SAP and EPC available as an upgrade
- Email support for Building Control queries
- Fast turnaround times
SAP Calculations Pricing
Our SAP prices are fixed and transparent, with no hidden extras. Each price covers one stage of the SAP assessment, either a Design SAP or an As-Built SAP with EPC, along with guidance to meet Part L and reasonable revisions included in the price. If we have already completed the Design SAP, a follow-on As-Built SAP with EPC can be added for a reduced upgrade fee.
New Builds
From £220
Extensions
From £150
Conversions
From £220
Fast 2-4 Day SAP Calculations: How It Works
Getting your SAP Calculation is straightforward. There is no complicated paperwork and we guide you through each stage from start to finish.
- 1
Upload your plans
Send us your drawings and basic project details. We review everything and confirm what is needed for compliance before any work begins.
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2
We complete your SAP 10 model
We build your SAP 10 energy model, calculating U-values, thermal performance and carbon emissions. Our thermal modelling ensures your building fabric meets Part L requirements. Unlimited revisions are included until the design meets the standard.
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3
Receive your SAP report
You receive your Design Stage SAP report along with clear guidance on how to stay compliant through the build. As-Built SAP and EPC can be added later when the project is complete.
SAP Calculations Requirements & Documentation
To complete your SAP Calculation we need a clear set of drawings and a few basic specifications. You can upload everything through our client portal, which keeps all documents in one place and allows you to track progress throughout the project.
- Floor plans with dimensions
- Elevations and sections
- A site plan showing orientation
- Construction details or a build-up summary
- Heating and hot water specification
- Window and door schedule
If anything is missing we will let you know straight away. Most projects can be completed from standard architect drawings and a few simple notes on the proposed construction and heating system.
Why Choose Our SAP Calculations Service
You work directly with an Elmhurst accredited OCDEA, not a call centre or anonymous team. We've got real world construction experience, so our guidance considers both regulatory compliance and how buildings are actually built on site.
What You Get With Us
- Direct access to qualified assessor
- Fixed pricing quoted upfront
- Fast 2-4 day turnaround
- Clear, practical guidance
- Construction industry experience
- Unlimited revisions included
What You Avoid
- Call centre responses
- Hidden fees and extras
- Weeks of waiting
- Technical jargon overload
- Academic-only perspective
- Revision charges
The Difference: Real World Construction Experience
We've run building projects before becoming energy assessors, so we understand both the regulatory requirements and the practical challenges you face on site. This means clearer guidance and solutions that actually work.
UK-Wide SAP Calculations Coverage
We provide SAP calculations across the entire United Kingdom. Our service covers England, Wales, Scotland and Northern Ireland, with reports accepted by all local Building Control bodies and Approved Inspectors nationwide.
England & Wales
Full coverage across all English and Welsh regions. Our SAP calculations comply with Part L Building Regulations and are accepted by local authorities from London to Newcastle, Manchester to Cardiff.
- London and South East
- Manchester, Birmingham, Leeds
- Cardiff, Swansea, Newport
- All counties and regions
Scotland & Northern Ireland
SAP calculations for Scottish Building Standards and Northern Ireland Building Regulations. We work with local Building Control across Glasgow, Edinburgh, Belfast and all regions.
- Glasgow, Edinburgh, Aberdeen
- Belfast, Derry, regional areas
- Scottish Building Standards compliance
- Northern Ireland Building Regulations
Working with Local Building Control
Our SAP reports are recognised and accepted by Building Control bodies across the UK, from local authority departments to private Approved Inspectors.
Frequently Asked Questions
How long does a SAP calculation take?
Most projects are completed within 2 to 4 working days. Larger or more complex builds may take a little longer, but we let you know the expected timescale as soon as we receive your drawings.
Do I need Part O as well?
Many new builds now require a Part O Overheating Assessment. If your design has large areas of glazing or bedrooms on upper floors, Part O is likely to apply. We can advise once we have reviewed your plans.
What happens if my SAP fails?
A fail result is common on first submission. We provide clear recommendations to bring the design into compliance. This may include improving insulation levels, reviewing glazing, or updating the heating specification. All revisions are included in the service.
Can you help make my design pass?
Yes. We guide you through each change needed to achieve compliance. We explain which adjustments have the strongest impact so you can make informed decisions with your architect or builder.
What is the difference between SAP and EPC?
A SAP calculation is the energy assessment that produces the data for an Energy Performance Certificate (EPC). The SAP evaluates thermal performance, U-values and building fabric efficiency, while the EPC is the final certificate showing the energy rating.
Do I get the EPC as well?
The EPC is produced at the As-Built stage. We can complete the As-Built SAP and lodge the EPC once the project is finished. This can be added as an upgrade whenever you are ready.
What do I need to send you?
We need floor plans, elevations, sections, a site plan, construction details, your heating and hot water specification and a window schedule. All documents can be uploaded through our client portal.
Will Building Control accept your SAP reports?
Yes. All reports are completed by an Elmhurst accredited OCDEA and meet the requirements for Part L compliance. Building Control accepts them throughout the UK.
Ready to get your SAP Calculation?
All SAP calculations completed by an Elmhurst-accredited OCDEA and accepted by Building Control nationwide.