A guide to energy efficiency audits.

With energy costs remaining a primary concern for UK households, understanding your property’s thermal performance is the first step toward effective retrofitting. Whether you need a standard EPC for a property listing or a deep-dive audit for a retrofit project, professional assessment ensures you invest in the right improvements.

What Does the Work Involve?

• Visual Inspection: A thorough walk-through to assess the age and construction of the property, including walls, roof, and floors.
• Insulation Check: Measuring the depth of loft insulation and identifying cavity wall or solid wall insulation.
• Heating Systems: Inspecting the boiler, heat pump, or electric heaters, alongside programmers, thermostats, and TRVs (Thermostatic Radiator Valves).
• Fenestration: Checking the type and age of windows and doors, specifically looking for double or triple glazing and draught-proofing.
• Lighting and Renewables: Recording the percentage of low-energy lighting and the presence of solar panels or heat recovery systems.
• Data Modelling: Entering measurements and observations into government-approved software (RdSAP) to generate an efficiency rating from A to G.

Typical Costs

The cost varies significantly between a standard EPC required for a sale and a bespoke, high-level energy audit involving thermal imaging or airtightness testing.

Prices are generally influenced by the size of the property and your location, with London and the South East often commanding higher rates. Most prices quoted by independent assessors include VAT and the £1.50 government register fee.

How Long Does It Take?

• Standard EPC Survey: 45 to 90 minutes on-site, depending on the complexity of the building.
• Full Energy Audit: 3 to 5 hours for a deep-dive assessment including thermal imaging.
• Report Turnaround: Usually 24 to 48 hours for the certificate to appear on the national register.

DIY or Professional?

You cannot produce your own EPC. By law, it must be carried out by an accredited Domestic Energy Assessor (DEA) to be valid for property transactions. While you can use DIY thermal leak detectors to find draughts, these results won't be recognised by mortgage lenders or for government grants like the Boiler Upgrade Scheme.

Always check the Domestic EPC Register to ensure your assessor is currently accredited and insured.

Choosing the Right Tradesperson

• Accreditation: Ensure they are a member of a government-approved scheme like Elmhurst, Stroma, or Quidos.
• Experience: Ask if they have experience with your specific property type, especially if you own a period home or a listed building.
• Questions to Ask:
  • Are you registered on the TrustMark or EPC register?
  • Does the quote include the lodgement fee for the national database?
  • How soon will the certificate be live after the visit?

UK Regulations

• MEES: The Minimum Energy Efficiency Standards currently require a minimum rating of 'E' for private rented properties.
• Validity: An EPC is valid for 10 years, but it is recommended to get a new one if you perform significant energy upgrades.
• Part L: Building Regulations Part L dictates the energy efficiency standards for new builds and extensions.

Common Problems

• Lack of Evidence: If you have cavity wall insulation but no paperwork or visual drill holes, the assessor must mark it as "unknown," which defaults to a poor rating.
• Restricted Access: If the assessor cannot access the loft or the hot water cylinder, they have to make "worst-case scenario" assumptions.
• Inaccurate Floor Plans: Incorrect measurements during the survey can lead to an inaccurate volume calculation, skewing the final rating.
• Missing Certificates: Always keep FENSA certificates for windows and MCS certificates for solar panels to ensure they are recorded correctly.

Frequently Asked Questions