Before submission
Early modelling can compare fabric and systems before procurement. Later modelling records the agreed design for the relevant regulatory submission.
Domestic energy assessment
SAP calculations for domestic projects
Understand the energy model, compare specifications and confirm the calculation your domestic project needs.
When you need this work
SAP is a standardised calculation methodology. Its value to a project comes from accurate inputs, timely option testing and clear control of changes between design and completion.
Briary reviews the building geometry, fabric, thermal bridging, ventilation, heating, hot water, renewable technologies and other relevant inputs. We separate confirmed information from assumptions and explain the changes that are most likely to improve the result. The exact methodology and compliance route depend on location, timing and the applicable regulations. This service is not an RdSAP survey service for existing-home EPCs.
For a complete new-home commission, see SAP for new homes. For work to an existing property, see extension and conversion assessments.
What we check
Through construction
Product changes, window schedules, airtightness results and thermal-bridge details can all affect the final calculation. We track the information needed to keep the model representative.
At completion
As-built information is checked against the design assumptions before final outputs are prepared. Differences are raised rather than silently carried forward.
Common coordination issue
A target U-value or generic product description is not a confirmed input. Identify which values are supported by drawings and product evidence, and keep proposed alternatives separate until the team has agreed them.
What you receive
SAP calculation
The appropriate design or as-built calculation for the agreed scope and methodology.
Action record
A concise explanation of missing information, key risks and recommended next decisions.
Supporting report
Relevant compliance reporting or data for the project team and building-control submission.
Getting started
What we need
Geometry
Dimensioned plans, elevations and sections, site orientation and a window and door schedule.
Fabric
U-values, construction build-ups, thermal-bridge values or details, airtightness target and test result where available.
Systems
Heating, hot water, ventilation, controls, lighting and renewable-technology specifications relevant to the calculation.
Before commissioning
When should SAP work start?
Before the fabric and systems are fixed. Early work leaves more practical options and reduces the risk of expensive late substitutions.
Can you model different specifications?
Yes. We can compare defined options, provided the question and inputs are clear.
Do you provide EPCs for existing homes?
We provide EPC support arising from relevant new-build SAP work. We do not offer RdSAP surveys for existing dwellings.
What does a SAP assessment cost and how long does it take?
We quote from the drawings and required output. Dwelling count, design variation, project stage, information quality, option testing, EPC scope and deadline affect the fee and programme. The written scope confirms both before work starts.
Sources and further reading
Use the edition, jurisdiction and assessment route that apply to the project. Publication of newer guidance does not automatically change an existing project’s requirements.
Get a clear SAP scope
Share the drawings, project location, stage and known fabric or services information. We will identify what is ready and what can follow.