The approved route
The March 2026 notice of approval identifies the 2026 National Calculation Methodology for buildings other than dwellings. Approved software implements the methodology through routes including SBEM and, where appropriate, dynamic simulation.
A BRUKL report records the compliance calculation for a new non-domestic building or qualifying work. It is an output of the approved modelling process, not a substitute for the coordinated design information used to create the model.
Information that affects the result
Geometry, activity types, fabric, glazing, air permeability, lighting, HVAC systems, controls and low-carbon technologies can all influence the calculation. Missing or late information is often replaced temporarily with assumptions, which can hide design risks or make the result less useful.
The strongest workflow begins before construction information is frozen. The assessor can identify sensitive inputs, issue an assumption schedule and update the model as the design develops.
A methodology under review
The government has also committed to a comprehensive review of the non-domestic National Calculation Methodology during 2026. Until a revised methodology is formally approved and brought into use, projects must follow the currently applicable approved route and transitional provisions.
For live work, confirm the building type, jurisdiction, regulatory stage and software version before starting the model.
Official sources
Need advice for a specific building or project?
Discuss an SBEM or BRUKL project