Room In Roof

At the time of writing the methodology for EPC assessments of existing dwellings is RDSAP 9.94. The much anticipated RDSAP 10 update is due in Q1 2025 and a significant methodology overhaul from RDSAP to the Home Energy Model (HEM) is proposed for 2026.

This is where a room or even a whole upper 'storey' in the property is located within the slope of a pitched roof.

Here is a nice example, located in the centre of Lacock in Wiltshire:

We'll add some content here about this subject shortly, but the main issues are with the level of insulation present and the documentary evidence required if work has been carried out since the property (or building part) was originally constructed.

The definition of Room In Roof is met when:

• 50% or more of the length of walls that face the eaves have an internal height that is less than 1.8m at what is often called the Common Wall (ie not any internal stud wall).
• A fixed staircase which one is able to walk up and down facing forwards.

Changes will be made shortly in RDSAP Version 10 which affect how a Room In Roof is assesssed.

Click here to return to our 'Improve Your EPC' main page, and see if there is another way you could improve your EPC rating.