Unheated roof space under a pitched roof

If you don’t use the loft for anything except storage, don’t heat it!

Lay 270mm — 300mm (11" — 12") of insulation between and over the joists in the loft, to bring it up to the same minimum standards as the latest building regulations.

If there’s already a thin layer of insulation, fill any gaps and lay new insulation on top.

Make sure the insulation fits snugly between the joists but be sure not to block any vents at the eaves (where the roof meets the walls). You will need to have vents fitted to keep a flow of air to the roof timbers if your roof is lined and isn’t ventilated (if you can’t see the tiles or slates from inside the loft and you can’t see daylight around the edges of the roof).

If there’s a cold water tank in the loft, it needs to be insulated to stop it freezing — easiest with a ready-made tank jacket.

Don’t lose heat through the loft hatch!

Use flexible draught strip around the hatch and if you can, fix rigid insulation to the back of it — or buy a ready-made insulated loft hatch. Fit bolts to ensure a tight seal.

If the loft is already boarded and you don’t want to remove the boarding, you could employ a specialist to blow insulation into the space between the boards and the ceiling below.

You must get a building warrant if you want to convert your loft into a heated room.

Insulate between and above the joists.

Prevent fires and heat loss by enclosing any recessed lights, clear of the insulation.

Insulation stops heat passing into the loft, so you need to insulate around any water tanks and pipes so that they don’t freeze — but don’t insulate below the tank.