Technical insight

What is the difference between SAP and SBEM?

A practical distinction between residential SAP and non-domestic SBEM assessment routes and when design teams should confirm the method.

The building use normally sets the route

SAP is used for dwellings, while SBEM is used for many non-domestic buildings. Mixed-use, conversion and unusual projects need the assessment route confirmed for the specific scope.

Both depend on coordinated inputs

Geometry, fabric, glazing, systems, controls and renewable-energy information must match the developing design. Poorly controlled assumptions reduce the usefulness of either assessment.

Assessment should start before design is fixed

Early modelling allows the team to compare practical changes to fabric and building services. A late assessment can identify compliance risk when options are more expensive to change.

Lodgement and evidence are separate responsibilities

The commission should state who prepares the model, supplies product evidence, completes as-built updates and undertakes any required final lodgement.

General technical guidance for England. Requirements, assessment routes and responsibilities must be confirmed for the specific building, location and commission.

Published 29 July 2026