Frequently Asked Questions

From major cities to rural districts, we prepare Energy Statements that match the exact requirements of your local planning department, ensuring a smooth and stress‑free planning process.

You can usually tell by checking your local authority’s validation checklist, planning guidance or any pre-application advice you’ve received. Most councils require an Energy Statement for new builds, larger extensions, mixed use schemes and commercial developments, but policies vary. If there’s any uncertainty, we can review your local requirements and confirm exactly what your project needs before you submit your application.

An Energy Statement is usually required at planning stage for new builds, larger extensions, mixed use schemes and commercial developments. Most UK councils request one to demonstrate how the proposal will meet local energy and carbon reduction policies.

We typically require floor plans, elevations, sections, site constraints, building specification, glazing details and the ventilation strategy.

The ideal time is RIBA Stages 2-3, when glazing, orientation and ventilation details are defined enough for accurate modelling but still early enough to make cost effective design changes.

Absolutely! We provide clear, actionable recommendations to bring the design into compliance.

We require floor plans, details of all proposed sanitary fittings, including flow rates, flush volumes and any water saving technologies.

Most assessments are completed within 1–2 working days once all information is provided.

If the calculation fails, it simply means the proposed fittings exceed the allowable water use limit under Part G. We identify which items are causing the issue (often taps, showers or WCs) and recommend straightforward, cost effective alternatives. Once updated flow rates or product specs are confirmed, we rerun the calculation and issue a compliant report.

Psi values quantify heat loss at junctions such as eaves, gables and corners. Accurate values improve SAP and SBEM results and reduce the risk of thermal bridging.

If your design uses non standard junctions/specification or you want to optimise SAP results, bespoke psi values provide more accurate and often more favourable outcomes.

We require detailed junction drawings, material specifications and construction build ups.

The notional dwelling is a theoretical benchmark building used in SAP to set the minimum energy performance targets your design must meet. It has the same size, shape and orientation as the actual dwelling, but uses a standardised set of fabric, heating and ventilation specifications defined in Appendix R of SAP. Its performance determines the Target Emission Rate (TER), Target Fabric Energy Efficiency (TFEE) and Target Primary Energy Rate (TPER) that your design must achieve or exceed.

Yes. Under current and future building regulations (Part L), almost all new dwellings require a renewable or low carbon technology to meet the carbon and primary energy targets. The notional dwelling now includes solar PV, which sets a much higher benchmark than previous regulations.While a very high performance fabric and airtightness strategy can reduce the gap, in real world projects it is extremely difficult to achieve compliance without at least one of the following:• Solar PV• Air source heat pump• Other low carbon heating technologyWe model the options and confirm the most cost effective route, but renewables or low carbon systems are now effectively a requirement for compliance.

If an SAP calculation fails, it means the design doesn’t currently meet the energy efficiency requirements of Part L. We can identify which elements are causing the shortfall (such as insulation levels, glazing, heating systems ect) and model practical, cost effective improvements. Once the preferred specification is agreed, we update the assessment and issue a fully compliant SAP report.

A conversion is any project where an existing building is changed into one or more new dwellings. This includes commercial‑to‑residential schemes, barn conversions, office or industrial buildings being repurposed, and the subdivision of a single property into multiple flats. If the work creates new dwellings through a change of use, it is classed as a conversion and requires SAP Calculations under Part L.

Yes. Once we’ve completed the SAP assessment, we provide clear, practical recommendations to help improve the dwelling’s rating. This can include upgrades to lighting, heating systems & controls, insulation, glazing, or renewable technologies. We prioritise the most cost effective measures and explain the impact each one will have on the final EPC score, so you know exactly where to focus your investment.

For conversions, SAP compliance is measured by checking that the building meets the minimum U‑value targets set out in Tables 4.2 and 4.3 of Part L1B. If the upgraded elements (walls, floors, roofs, windows and doors) achieve these required U‑values, and the completed dwelling achieves an authorised EPC rating, the conversion is considered compliant.

SAP calculations are required for extensions to demonstrate compliance with Part L1 of the Building Regulations. The main trigger is when the proposed glazing exceeds 25% of the extension’s floor area. If the amount of glazing is above this limit, an SAP assessment is needed to show that the design will not lead to excessive heat loss.The SAP calculation checks that the new thermal elements such as walls, roofs, floors, windows and doors meet the minimum U‑value targets set out in Tables 4.2 and 4.3 of Part L1B. If these elements achieve the required standards and the overall design performs efficiently, the extension can be signed off as compliant.

To begin the SAP calculations, we need the existing and proposed drawings, details of the extension’s construction build‑ups, the heating and hot‑water system, ventilation strategy, and any planned improvements to the existing property. If anything is missing or uncertain, we guide you through exactly what’s required so the assessment can proceed smoothly.

If the SAP calculation for your extension fails, it means the design doesn’t currently meet the energy efficiency requirements of Part L. We identify exactly which elements are causing the issue, often insulation levels, heating efficiency or the need for improvements to the existing property. We then recommend practical, cost effective upgrades. Once the updated specification is agreed, we rerun the assessment and issue a fully compliant SAP report.

SBEM (Simplified Building Energy Model) calculations assess the energy performance of non‑domestic buildings in line with the UK’s National Calculation Methodology. They form the basis of Part L compliance for commercial projects, modelling how a building uses energy for heating, cooling, ventilation, lighting and hot water. The output is a BRUKL report that confirms whether the design meets the required carbon and primary energy targets set by Building Regulations and a EPC at as-built stage.

SBEM is required for all new non‑domestic buildings, as well as extensions over 100 m² or those that increase the existing floor area by more than 25%. It also applies to shell‑and‑core developments, material changes of use, major refurbishments and temporary buildings used for more than two years. In short, if a commercial building is being built, extended or significantly altered, SBEM calculations are typically mandatory.

A BRUKL (Building Regulations UK Part L) report is the official output from SBEM and shows whether a building complies with Part L. It compares the Building Emission Rate (BER) and Building Primary Energy Rate (BPER) against the regulatory targets, and confirms whether the building meets minimum standards for insulation, glazing, HVAC efficiency, lighting and solar gain control. Building Control relies on the BRUKL report at both design and as‑built stages to approve compliance.

L2A and L2B refer to the two categories within Part L for non‑domestic buildings. L2A covers new‑build commercial properties and sets out the full compliance requirements for new construction. L2B applies to existing buildings undergoing extensions, refurbishments or conversions, where the focus is on improving the performance of the affected elements while ensuring the overall building meets minimum standards. The correct category ensures the right methodology and evidence are used for compliance.

SBEM calculations are required to demonstrate compliance with Approved Document Part L and to ensure commercial buildings meet modern standards for energy efficiency and carbon reduction. They provide a clear, regulated method for assessing performance and are essential for issuing the Energy Performance Certificate (EPC) at completion. Without SBEM, a non‑domestic building cannot legally be signed off by Building Control or sold or rented on the market.

Yes. Once we’ve completed the SAP assessment, we provide clear, practical recommendations to help improve the home’s rating. This can include upgrades to lighting, heating systems & controls, insulation, glazing, or renewable technologies. We prioritise the most cost effective measures and explain the impact each one will have on the final EPC score, so you can make informed decisions about where to invest.

An EPC is required when selling, renting or significantly modifying a commercial property.

Yes. After completing the SBEM assessment, we outline targeted, commercially focused recommendations to improve the building’s rating. These may include HVAC upgrades, improved controls, LED lighting, insulation enhancements or renewable technologies. We highlight the most cost effective measures and show how each one influences the final EPC rating, helping you plan improvements with confidence.

Yes, we complete on site assessments to gather accurate data for the EPC.