An SBEM Assessment remains a legal requirement for all new and existing non-domestic buildings under Part L of the UK Building Regulations. This process evaluates a building's energy efficiency by calculating carbon emissions and primary energy demand. It uses the Simplified Building Energy Model (SBEM) or approved software tools to compare the proposed building against a notional structure of similar dimensions.

For architects and M&E consultants operating in London and the East of England, this guide explains how to stay compliant with 2025 SBEM regulations. It outlines the mandatory energy targets, evaluation metrics, and reporting obligations in straightforward terms.

Why Are SBEM Assessments Required in 2025?

UUnder Regulations 24–27C of the Building Regulations 2010 (as amended), any non-domestic new build or major alteration must demonstrate compliance with two key metrics:

Target CO₂ Emission Rate (TER) – This determines the allowable carbon output.

Target Primary Energy Rate (TPER) – This defines the total allowable primary energy demand.

These benchmarks help align the UK's building stock with national carbon reduction goals. To achieve this, you must submit SBEM Assessments at both the design stage and after construction.

When Are SBEM Assessments Needed?

You’ll need an SBEM Assessment if your project involves:

• Constructing a new non-domestic building
• Undertaking a significant refurbishment that changes energy status (e.g., from unheated to heated)
• Extending a commercial building
• Changing a building's use (e.g., converting a house into an office)

You should notify Building Control before work begins. After completion, you must submit the as-built report within five working days.

What Does an SBEM Assessment Include?

An SBEM assessment benchmarks a building's performance against a notional equivalent. It covers:

Building fabric – U-values for walls, floors, roofs, windows, and doors must match or outperform regulatory standards (as per Approved Document L).

Airtightness – Most buildings over 500m² require an air pressure test to confirm air permeability does not exceed 8 m³/h·m² @ 50Pa.

HVAC and control systems – Heating, ventilation, and cooling system efficiencies, zoning, and automation all influence the calculation.

Lighting – Performance is based on efficacy, daylight sensors, and automatic controls.

Solar and shading – Orientation, glazing, and external shading strategies impact summer performance.

Renewable technology – SBEM accounts for solar PV, heat pumps, and CHP. Under Regulation 25A, you must assess their feasibility.

Occupancy and use profiles – Each area must be assigned an activity type.

These details feed into approved SBEM software to generate the BRUKL report for compliance verification.

Level 3, 4, and 5 SBEM Explained

The assessment level for a commercial EPC or SBEM Assessment is based on the building's complexity, size, and services:

Level 3
Applies to simple, minimal zoned buildings with basic heating systems and straightforward layouts. Typical examples include small shops, standalone restaurants, or uncomplicated office spaces. These buildings have no mechanical cooling or advanced controls.

Level 4
Covers buildings with more sophisticated services and zoning requirements. These include offices, hotels, or retail outlets with air conditioning, mechanical ventilation, or central heating systems. Most modern commercial developments fall under Level 4.

Level 5
Reserved for complex or unconventional buildings with advanced systems or geometry that standard SBEM tools cannot model effectively. Examples include large shopping centres, buildings with atriums or complex curtain walling, and those using innovative HVAC or renewable setups. Level 5 assessments require dynamic simulation modelling (DSM).

Selecting the correct level is crucial for legal compliance and energy performance accuracy. Our qualified team offers comprehensive SBEM services across all three levels throughout Colchester and the surrounding areas of Essex, Suffolk, Norfolk, and Cambridgeshire

Key SBEM Assessment 2025 Compliance Criteria

Meet energy targets
Your building design must stay within the permitted carbon emissions and energy consumption limits.

Consider efficient systems
Before construction begins, you are required to evaluate the use of high-efficiency technologies, such as heat pumps or solar panels, in line with Regulation 25A.

Prove airtightness
Some commercial buildings must pass an air permeability test to demonstrate that they are well-sealed.

Test your systems
All heating, ventilation, and cooling systems should be fully commissioned and tested to ensure proper function and compliance.

Submit reports
At completion, you must submit both a BRUKL compliance report and an Energy Performance Certificate (EPC) to the local authority.

How SBEM Differs from SAP

SBEM – Used for commercial and public buildings
SAP – Required for residential dwellings

Both use different algorithms and assumptions. If your project includes both residential and non-residential space, you may need both assessments.

Preparing for an SBEM Assessment

To avoid delays and costly revisions, follow these preparation tips:

• Provide complete architectural, mechanical, and electrical drawings
• Include fabric specifications with confirmed U-values
• Confirm all on-site energy systems in the design

Early engagement with your assessor speeds up the process and improves accuracy.

Cost of SBEM Assessment in 2025

Indicative pricing for an SBEM Assessment

Serving Colchester, Essex, Cambridgeshire, Suffolk, and Norfolk

Our team delivers fully compliant SBEM Assessments across Colchester, Essex, Cambridgeshire, Suffolk, and Norfolk. Whether your project involves a simple retail unit or a complex multi-use facility, we provide expert support from the design phase to the final EPC submission.