A SAP (Standard Assessment Procedure) calculation is the government-approved method of demonstrating compliance with Building Regulations Part L for new dwellings, conversions and extensions. We deliver SAP 10.2 calculations nationwide from your drawings — no site visit required at design stage.
At design stage for new-build dwellings (Part L1A), for material change of use conversions creating a new dwelling, and for extensions above certain glazing thresholds. Also required for as-built EPC lodgement at completion.
SAP 10.2 is the current version of the UK Standard Assessment Procedure. It models fabric U-values, thermal bridging, ventilation, heating, hot water, lighting and renewables to produce a Dwelling Emission Rate (DER) compared against the Target Emission Rate (TER).
The Home Energy Model (HEM) is expected to replace SAP for new dwellings in coming years. We track the transition and will move projects onto HEM once it is the required methodology.
Scaled architectural drawings (PDF is fine, DWG/IFC even better), fabric specifications (U-values or build-ups), heating and hot water system details, and any renewables specified. We turn a single dwelling around in 5 working days from receipt of the pack.
At handover we return to produce the as-built SAP and lodge the on-completion domestic EPC. Substitutions during construction can be modelled at that stage.
Yes, SAP calculations are legally required for all new build dwellings, conversions to dwellings, and certain extensions in England and Wales. They demonstrate compliance with Part L of the Building Regulations and are needed at both design stage (before construction) and as-built stage (for completion sign-off and EPC lodgement).
SAP (Standard Assessment Procedure) is the current UK methodology for assessing dwelling energy performance. The Home Energy Model (HEM) is the government's planned replacement, designed to be more accurate and support the Future Homes Standard. SAP remains the compliance route until HEM is formally adopted. Energy Performance Direct designs SAP models in a HEM-ready way to future-proof your project.
Yes, all our SAP calculations are carried out remotely. We work from your architectural drawings, construction specifications, and system details. Remote delivery enables fast turnaround, competitive pricing, and access to specialist expertise regardless of your location in the UK.
We need architectural drawings (plans, elevations, sections), construction specifications (wall, floor, roof build-ups with U-values), window and door specifications, heating system details, ventilation strategy, and any renewable technologies. We can work from draft designs at design stage and as-built specifications for completion.
Standard SAP calculations are typically completed within 3-5 working days from receipt of complete information. Complex projects with non-standard construction or multiple dwelling types may take longer. We offer expedited services for urgent projects.
Yes, we have specialist experience modelling SAP for natural and non-standard construction methods including hempcrete, straw bale, cob, SIPs, ICF, and timber frame. These require careful interpretation within SAP to ensure compliance while accurately reflecting real-world thermal performance.
Send drawings — get a SAP quote
Call 01392 980077 or get a quote online.