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New-build residential compliance

New Build SAP Calculations from design to compliance.

Design-stage SAP calculations for architects, developers, housebuilders and self-builders, providing the evidence needed to demonstrate Part L compliance for new homes.

Architects Developers Housebuilders Self-builders
house being built
The service

Use SAP to guide the design, not just check it at the end.

Every new dwelling needs a SAP assessment to demonstrate its predicted energy performance under Part L. Starting at design stage gives the project team time to understand how the building will perform and where changes may be needed.

We model the proposed building, assess energy performance and identify practical improvements while there is still time to make changes. This turns the calculation into a useful design tool rather than a late-stage compliance check.

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SAP calculations for individual homes and multi-unit developments

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Review against current Part L requirements

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Practical feedback where the initial design needs improvement

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Coordination with architects, designers and building control

Need help?

Not sure exactly what you need?

Send us your drawings, planning information or building control requirements and we can confirm the right assessment for your project.

Get a quote → 📞 0330 043 9275
Who it is for

The right support at the right project stage.

CLIENT TYPE

Architects and designers

Test the proposed fabric, systems and specification early, while changes can still be made efficiently.

CLIENT TYPE

Developers and housebuilders

Coordinate Part L requirements across individual homes and multi-unit residential developments.

PROJECT TYPE

Self-builders

Understand what the proposed home needs to demonstrate before construction progresses.

PROJECT STAGE

Concept to technical design

Start early, while updates to the design and specification can still be made before submission.

What we assess

The design choices that determine energy performance.

We assess the proposed dwelling as a whole, looking at the fabric, systems and energy performance requirements that contribute to Part L compliance.

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Building fabric and U-values

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Thermal bridging and air permeability

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Heating and hot water systems

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Ventilation strategy

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Glazing, orientation and solar gains

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Renewable and low-carbon technologies

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Part L targets and predicted energy performance

How we work

A clear process from information to issue.

01
Step 01

Send the drawings

Provide the plans, elevations and specification information available for the project.

02
Step 02

Build the model

We model the proposed dwelling, including the fabric, systems, ventilation and renewable technologies.

03
Step 03

Review and refine

We review the results and provide practical feedback where changes can improve compliance.

04
Step 04

Issue the assessment

You receive the completed assessment and clear information for the next stage of the project.

What you receive

Clear outputs for your project team.

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Design-stage SAP calculation

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Part L compliance output

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Schedule of modelling assumptions

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Practical design feedback where needed

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Route to as-built SAP and EPC lodgement

Not sure what your project needs?

Send us your drawings or project information and we can help identify the right assessment for your project.

FAQs

Common questions

When should I commission a new-build SAP?

Ideally, SAP calculations should be considered at design stage, so the proposed fabric, systems and specification can be assessed while changes can still be made efficiently.

Does every new home need a SAP calculation?

New dwellings generally require a SAP assessment to demonstrate compliance with the relevant energy performance requirements under Part L.

What happens if the first design does not pass?

We identify where improvements are needed and provide practical feedback so the design can be refined before the assessment is finalised.

Can you complete the as-built SAP and EPC later?

Yes. The design-stage assessment provides a route towards the as-built SAP and EPC once the development is complete.