SBEM calculations: what the design team needs at design and as-built stages
Organise drawings, specifications and changes so non-domestic energy modelling can support the actual building.
Define the purpose of the calculation first
SBEM, the Simplified Building Energy Model, is used in the approved national calculation approach for many non-domestic buildings. A project might need modelling for a design-stage Part L assessment, an as-built submission or a non-domestic EPC. Those outputs are related, but the evidence and timing are not identical. Confirm the building's location, intended use, applicable regulatory route and required deliverables with the design team and building control before pricing the work. The Approved Document L collection includes the 2026 guidance for buildings subject to that standard and earlier editions for projects to which previous standards still apply.
Give the modeller a coherent building description
Provide current plans, sections and elevations showing dimensions, floor levels and orientation. Mark heated, cooled, naturally ventilated and unconditioned areas. A shop with offices above, a warehouse with a heated office or a building with several tenants can need careful zoning. If drawings are still developing, label the revision and explain what may change. A model based on outdated plans can create rework rather than useful design feedback.
Match the specifications to the model
Collect the proposed fabric build-ups and glazing details, then the heating, cooling, ventilation, hot-water, lighting and control strategy. Unknown values should be identified as assumptions, not quietly presented as installed equipment. Design-stage modelling can test options while there is time to alter the scheme. At as-built stage, confirm the actual products, commissioning results and material changes against the design model. A late plant substitution or glazing change can affect the outcome.
Keep the deliverables distinct
A BRUKL or other compliance output does not by itself replace every document needed at handover, and a commercial EPC is a separate certificate for an eligible building. Our SBEM calculations service invites project-specific details so the scope can be agreed. If the task is an EPC for an existing office, retail unit or warehouse, the service directory explains that separate route.