Room in the Roof.

Original Article
February 10th, 2018


For the purposes of RdSAP, a room in the roof is classified as such where the height of the common wall (not any internal stud wall) is less than 1.8m in height for at least 50% of its length.

On the other hand, if the exposed external common wall is equal to or greater than 1.8m, then it is not recorded as a room in the roof but as an additional storey.  

The room in the roof should be accessed via a fixed staircase (i.e. walking up and down face forward) and it does not have to contain any habitable rooms.

A timber dormer is in the roof area of a cavity wall constructed property. Even though it may be 1.8 or more in height, it is still a room in the roof as there is no common wall extending up from the ground floor.