Roofing Insulation

K09

Hi,

I am moving into a house with a G energy rating. The first thing I want to do is to insulate the roof.

What is the best way to do this? Is it to insulate on the attic floor or on the rafters on roof?

Also what is the best available material and standards?

Thanks!!

soldsold

Insulate between the ceiling joists with the cheapest pink wool you can get, should be about 1.50 per m2 for 100 mm thickness. Then roll out another layer on top of the joists at 90 degrees. Try to get 300mm thickness.

Don't insulate under the water tank or you risk freezing it, instead co tinue the insulation around and over the tank and any exposed water pipes. This all assumes you aren't using the attic. If you need storage, put down the pink wool between the joists and you can get insulation boards you can walk on, someone here might be able to suggest what the best bet is. Make sure not to tuck the insulation into the eaves too tight as you need a 50mm gap behind the slates/felt for air to circulate in the attic. You can buy 50 mm thick plastic vents that fit in tight under the eaves or make up a diy version with offcuts of plywood and 2x1's, again there is probably an easy way to do this that someone here will suggest. Stick a piece of insulation board (polyurethane or polystyrene) to the back of the attic trapdoor.

Then look for draughts around windows and doors and attic trap door and apply foam draughts stop, it's in any hardware store. Check the letterbox etc.

Viking House

Try to go for a good quality roof insulation with a good density (30kg/m3) at least. I prefer Rockwool insulation batts, as rolls are often inconsistent.