Fix insulation to back of plasterboard

BarraOG

We have a room in our attic that was built without planning and I had to get retention for it after buying the house. All of the walls and ceilings appear insulated except for one wall which is adjacent to the rest of the attic. This wall consists of a wooden frame with plasterboard with foil on the back. There is also a cubbyhole door in the wall itself which consists of a sheet of plywood - 2 feet by 3 feet approx. I plan to insulate behind this wall but am not sure how to best keep the insulation up tight against the back of the plaster board. Any tips? Also, how might I deal with the cubbyhole so that it is insulated and draft free? If we were to make this room into a spare room, then the headboard would be against this wall due to the shape of the room.

listermint

Your insulation should be cut to the size of each stud opening and palmed into place . The fit should keep it in situ

D13exile

I'm finishing off my own attic at the moment. I used xtratherm rigid foam insulation in the walls (100mm) and 80mm between the rafters (allowing a void for air to circulate and remove moisture). Cut the insulation to size (allow a mm extra to ensure a tight fit and as the previous poster said, push it into place. Be careful if working over your head as the dust from the insulation will irritate your eyes. A dust mask is also essential. Once the insulation is in place, put insulated plasterboard over this. I used 37.5 mm insulated boards. Tape the joints well before plastering over.

As for the door opening, place some rigid insulation onto the back to cutt down the heat loss through the door. You can also use a draught seal around the opening of the door and strong magnets to hold the door tight to the seal.

As attics aren't usually built to standards, fire doors and smoke alarms should also be installed. I've gone further by placing a fire extinguisher under the stairs, in the hot press and on the attic landing. Overkill I know but you never know.