New Build SAP calculations

L1A SAP calculations conducted by experienced assessors. 

Speak to one of our team members

New build SAP calculations - L1A

In order to legally sell or rent a property you will need to provide your building inspector with a completed SAP calculation. This is just one component needed to pass building regulations. 

New build SAP calculations are separated into two stages. These stages determine how energy efficient a building is and are enforced by the government.

1.) Design Stage

2.) As Built Stage


A successful SAP calculation is completed when the Dwellings Emission Rate (DER) does not surpass the Target Emissions Rate (TER). The Dwellings Emissions Rate is calculated based on the specification and design of the dwelling. The Target emissions rate sets the lowest adequate level of performance for a SAP. 

Design - stage SAP calculations

SAP calculations are completed by accessing your building plans and elevations. Once these drawing have been received, one of our SAP assessors can make an assessment on your proposed building to complete your EPC.   During the SAP design stage, changes may be made by your architect with the intention of building the most energy efficient dwelling possible. We may also instruct you at this stage on the most suitable and cost effective methods of implementing these changes.   

Occasionally SAP calculations do need to undergo changes. Our SAP assessors are here to provide you with low cost solutions to amend any changes that need implementing so you can receive the pass you are aiming for.  Examples of this could be a more air tight building or improved insulation. See Air Tightness Testing for more information. 

After a final specification has been agreed with you and your architect, we can produce a design stage SAP calculation for your building control officer. 

What our SAP assessors need from you:

Drawings :

Elevation Drawings 

Floor Plans

Section Drawings

Site Plans







"U" values

"U" values are the rate at which heat passes through the fabric of a building or the performance of the thermal elements. Having a higher U value means you are loosing more heat from the building. U values are calculated by:

  • Type of building

  • Floors

  • Walls

  • Roofs

  • Openings (windows, doors, roof lights)

  • Ventilation

  • Main and secondary space heating

  • Hot water generation

  • Renewable technologies, including photovoltaic panels and solar water heating

  • Energy efficient lighting

As built SAP calculations

After you receive your air pressure test results one of our SAP assessors can edit the SAP so they correlate with one another.  SAP software is then used to check the results meet the specified criteria to pass the EPC.  If more remedial work is needed to achieve a pass, we will guide you on the necessary procedures.

The design stage SAP and as built SAP will then be used to create an EPC, which will sent to building control for the final sign off procedure.   

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