How do you insulate roof rafters with Celotex?

The usual way to do this is by inserting rigid insulation boards between the rafters. They should be cut to exactly the right size so they fit snugly and don’t allow any draughts through. To get the required 270mm thickness of insulation, you may have to insulate over the rafters as well, using insulated plasterboard.

The usual way to do this is by inserting rigid insulation boards between the rafters. They should be cut to exactly the right size so they fit snugly and don’t allow any draughts through. To get the required 270mm thickness of insulation, you may have to insulate over the rafters as well, using insulated plasterboard.

Also Know, can you use Celotex 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).

Keeping this in consideration, how do I fix Celotex to rafters?

Install Celotex insulation boards with both edges supported by rafters. Cut the boards using the Celotex Insulation Saw to rake and splay at ridge and verges to ensure close butted joints. Use large headed nails to temporarily fix board in place, until permanently secured by counter battens.

Should I insulate roof rafters?

Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. You can add insulation to the floor; the more the merrier. Also, make sure the attic is well ventilated. Cold roofs prevent ice dams.

What insulation do you use between rafters?

You can use rigid insulation board, carefully cut to size, or you can have foam insulation sprayed between the rafters.

Is it better to insulate ceiling or roof?

As mentioned earlier, attic ceiling insulation is easier and less expensive than roof insulation. Installing (or adding) insulation to the ceiling plane is rather straighforward. And you may use very different insulation materials. Cellulose and other fibrous materials are good and inexpensive choices.

Can you have too much insulation in your attic?

Without proper ventilation, a home can build up too much moisture, especially in the attic (warm air rises), which can cause mold problems and, overall, lower indoor air quality. This is not to say that if you have mold in your home, too much insulation is the culprit.

What is the best roof insulation?

ISOTHERM is a 100% green insulation product soft to touch and quick to install in the roof or attic space. Roof Insulation products like Isotherm are eco-friendly insulation products. The 145mm Isotherm insulation is SANS compliant and is the best insulation for your roof.

Does roof insulation make a difference?

Insulation batts, correctly installed in the walls and ceilings will vastly reduce the amount of energy required to heat the house in winter, and keep it cool in summer. Yes, not only will you create a more comfortable flooring temperature, you will also save on your energy bills.

Can you use Celotex between ceiling joists?

It’s also worth mentioning that Celotex can be used to top up insulation levels in a horizontal ceiling when mineral wool exists between the joists. Ensure ceilings are strong enough to withstand loadings associated with insulation.

How much Celotex do you need for rafters?

…the thickness of Celotex FR5000 placed between the rafters is the depth of the rafters less the depth of the airspace above. For example, where rafters are 150mm deep and a black sarking membrane is used, then 100mm of FR5000 can be installed which still leaves a 50mm gap for a fully ventilated airspace.

Can you screw into Celotex?

It would be possible to drill through the foam into the blocks and use a long screw-type fixing, but for a string dispenser, not worth the trouble. Use no-more-nails to glue it to the wall. If the glued surface area seems too small, glue a wooden batten to the wall and fix the dispenser to that.

Can you stick plasterboard to Celotex?

Try using Everbuild Dry Fix it’s magic! You squirt the stuff on the back of the plaster board around the edges and across the centre, leave for 5 minutes and then press the board onto the Celotex. Make sure the the board surface is Celotex surface is dust free.It sticks like you know what.

Do you need a Vapour barrier with Celotex?

I use Celotex or Kingspan insulation boards which are foil faced, and then I cover them with separate plasterboard. The cheapest insulated plasterboard which uses expanded polystyrene does NOT have a vapour barrier, so don’t use it!

Does Celotex require an air gap?

Depending on the specifics of the roof, it may be possible to fully fill the rafter depth or, in most cases leave a 25mm or 50mm air gap between the top face of the insulation and the sarking membrane.