Can Celotex be used for loft insulation?
Using rigid insulation board as loft insulation Some people may prefer to use rigid insulation board to insulate the loft space – for example Celotex or Kingspan – the process is pretty similar to above, although you will need less depth to achieve the same insulation levels (than mineral wool).
What U-value does 100mm Celotex?
0.2 W/m2k
Using Celotex to fill the cavities is more expensive, but you will only need to use 100mm celotex to achieve a U-value of 0.2 W/m2k .
Is 100mm loft insulation enough?
In the 1980s, it was quite standard to install any thickness from 25 to 50 mm. Then, building regulations stated that homes should have as much as 100 mm of loft insulation. This gradually increased to 200 mm and now stands at 270 mm for new builds and is recommended for other properties (but not essential).
What is the best insulation for a loft conversion?
Roof Room Building Regulations At present, building regulations for loft conversions dictate that the roof’s U-value must be 0.18W/m² or below. This equates to a 270mm thick layer of fibre/wood insulation, 175mm of board insulation or 125mm of high-performance spray foam.
Is Celotex better than rockwool?
Quilt is not “poorer” than Celotex, it is just less efficient heat insulator at the same thickness. Rockwool is fire resistant too, whereas Celotex it’s not. Rockwool has better sound resistance at a given thickness too.
What insulation has the best U value?
The best currently available is the Val-U-Therm system (available from Scotframe) with a U value of 0.09W/m2K from a wall thickness of 235mm, plus the outer skin. Changing the 140mm mineral wool in a timber frame to 140mm polyurethane would give the same U value as a SIPs panel.
What insulation do I need for loft conversion?
At present, building regulations for loft conversions dictate that the roof’s U-value must be 0.18W/m² or below. This equates to a 270mm thick layer of fibre/wood insulation, 175mm of board insulation or 125mm of high-performance spray foam.
What insulation is needed for a loft conversion?
Currently, building regulations for loft conversions dictate that the u-value of the roof must be 0.18W/m2 or lower. This equates to a thick 270mm layer of fibre or wool insulation, about 175mm of rigid board insulation or around 125mm of high performance spray foam.
Do you need Vapour barrier with Celotex?
You must use a vapour barrier otherwise warm air, which contains more water than cold, may get through to the cold outer fabric. If it does, and cools, you’ll get condensation.
Is Celotex better than polystyrene?
polystyrene is cheaper than celotex. R value or 50mm polystyrene is 1.25. R value of 50mm Celotex is 2.25. It has to be noted that over 7-10 years Celotex will drop in R-value to match the polystyrene as polystyrene will not drop.
Is 50mm Celotex better than Rockwool?
90mm Celotex or equivalent will give the best insulation, it’s insulation factor is about twice that of Rockwool. But it needs cutting which takes time and is messy. Rockwool might be easier to install, although you have to keep it in place somehow and if installed vertically ain’t so simple. Its also cheaper.
What is the best R-value for roof insulation?
Depending on where you live and the part of your home you’re insulating (walls, crawlspace, attic, etc.), you’ll need a different R-Value. Typical recommendations for exterior walls are R-13 to R-23, while R-30, R-38 and R-49 are common for ceilings and attic spaces.
Is new loft insulation better than old?
Many specialists will install new installation on top of the old and they will try to lay it crossways, if the old insulation is to joist depth. That way they will cover any holes or gaps that there may have been in the old insulation. This gives you more insulation and therefore less heat lost!
