Room in roof insulation is shown in the picture above.  There can be four or five areas to consider with ‘warm roof insulation’; slopes, gable wall, residual area and stud walls as well as sometimes a ‘flat roof area’.

The slopes are self explanatory and consist of rigid board insulation being installed between the rafters with an air gap behind, allowing for the roof timbers to ‘breathe’ and prevent moisture build up.

The gable wall, is the wall area of the room which is the external wall of the roof area.  If the party wall which adjoins your property, is shared with an uninsulated room next door, it is also sensible to insulate this wall too.  This avoids a cold bridging risk where damp can be attracted and can create an area where mould can occur

The residual area is the area in the eaves, behind a stud wall, where we would insulate the floor area, in much the same way as we would in a loft space

The stud walls can be insulated on the back, within the residual area, using loft roll/fibre slabs, and secured with netting, or we can insulate the outside of the stud walls using rigid board insulation.  The will depend on the space available inside the residual area and within the room, as some room space could be lost if using rigid board insulation

The flat roof element, as shown on this picture, is the flat section at the apex of the ceiling, and can be over-boarded with rigid insulation to ensure no area is left uninsulated, creating a thermal bridging risk