Frequently Asked Questions

Q1. We recently installed new electric radiators in a property, having been told these were highly efficient. However, when it came to having the property assessed for the EPC a poor rating was given. Why is this?

A1. The EPC rating is based on the running costs for the dwelling calculated using SAP. Electricity is a relatively expensive fuel (around 3 to 4 times the price of mains gas), so even though all direct electric heaters are 100% efficient, the use of electric heating usually results in poor ratings. However, electric storage heaters can make use of cheaper electricity available at nighttime, so usually result in a better EPC rating than direct electric heaters.

Q2. When is the Product Characteristics Database updated?

A3. The PCDB is updated overnight on the last day of each month, so any new products added will be available in assessments from the start of the new month.

Q3. Can you tell me when a particular product will be added to the Product Characteristics Database?

A3. We can only discuss progress with PCDB applications with the manufacturer/applicant since this is potentially commercially sensitive information.

Q4. Why can’t I select an infra-red heater in SAP software?

A4. There is currently insufficient evidence of the performance of infra-red heaters to justify modelling them differently from other direct electric heaters, so they are treated as having the same performance.

We’ll add more FAQs to this page in future. If you have a question not answered above, please email [email protected].

There are some further FAQs about EPCs on the Ministry of Housing, Communities and Local Government’s EPC FAQs page.