Loft insulation?

Question

I have no insulation at the moment. I have a 70 mm height for the ceiling rafters.

UK government advice is to have 270 mm fibre wool insulation but I need to board up the loft to use for storage.

I would have to extend the wooden supports by 200 mm which does seem to be a lot of work and have concerns extending the height with no side support.

Has anybody tried thin insulation either Airtec or Actis Tri ISO Super 10?

Which one would you recommend? Or is there another option I should try.

Answer 1

dont bother with the other answers mate, compressing insulation makes it useless, it is the air trapped in the insulation which retains the heat. The best solution for you is to buy 8' x 4' sheets of Kingspan, this is the rigid sheets of insulation which come in 70mm depth, perfect for you, very easy to install, just measure inbetween your joists and cut with a hand saw. The guideline reference of 270mm is only for rockwool.

Answer 2

I have maximum insulation everywhere. Two layers in the loft where most heat is lost. When we went up to get the Christmas decorations down it was as cold as outside up there. My boiler only comes on occasionally and I'm lovely and warm. Water supply underground from road froze Sunday -9 degrees. Can't compare fuel bills yet but my oil is lasting much better. This is a timber framed building and DOES have max insulation built in so not sure what John means. Stay safe everyone

Answer 3

Put down a good thick layer of insulation and when the time comes to board over the loft then just compress the insulation under them. Any insulation is better than no insulation.

Answer 4

Fit whatever insulation will fit in the 70mm space and then overboard with something like "Supadeck" (Insulated board)

With such thin ceiling joists, I'd be concerned about putting any signifigant weight up in the loftspace. You may be best adding depth to that 70mm with some 2*2 and then insulating/overboarding..

Answer 5

dont worry about government advice. be practical and fill the the insulation to the top of the joists, then board over them.

tip: the insulation will come in rolls. measure the gap between the joists and cut straight through the insulation whilst still in its package, its less messy, gives a better cut and will fit 100%. (rockwool or similar)

Answer 6

This is just a recommendation. There are thousands of houses without any kind of loft insulation. Even newspaper is better than nothing.

Answer 7

batt blocker, chicken wire, 1 x 4's ....up against the attic side of the wall. anthing to keep the batt up against the air conditioned space (heat or cool )

Answer 8

have used tri iso 10 many times ..best on market ..bit difficult to cut ..but practise makes it OK ..its the equivalent to 250mm of fibreglass.....without the irritation !