During an EPC assessment, the assessor will spend between 45 and 90 minutes inspecting your property. The exact time depends on the property’s size and complexity. They will measure windows, doors, calculate the floor area, heat loss and party walls, and access roof spaces to understand your home’s fabric and insulation levels.

Heating systems, ventilation, hot water systems, and any renewable technologies like solar panels or heat pumps are carefully examined. The assessor will also note fuel types and controls, including thermostats and programmers.

With RdSAP 10, the EPC assessment data collection is more detailed than before, helping produce a more precise energy rating. The process is non-invasive; the assessor won’t drill holes in walls or ceilings or move furniture or personal items, but will need access to all rooms, the loft, boiler, and meters.

If the assessor is unable to physically evidence an item such as wall or floor insulation then they may not be able to include that in their report. It can be beneficial to liaise with your assessor to ensure you have the correct documentation available when they arrive.

You don’t usually need to be present, but being available to answer questions can help clarify any unique features of your property leading to a more accurate rating.

You can read more about the process here.