Attaching Insulation board to joists

[Devonish]

I have to put 100mm Insulation between the ceiling joist and cover the whole ceiling with 40mm insulation board.

Can I glue the 40mm boards to the wooden joists? and if so what would I use?

 

[catlad]

Friction fit the 100mm between your joists then screw insulated plasterboard
to your joists.

 

[noseall]

We partially tack the inso boards then fully fix the plasterboards through both. It is more economical to fix them in two separate layers in any case.

 

[bluebaron]

I agree with noseall. I'm doing the exact same thing at the moment abet with 150mm overlay with 12mm. I spoke to celotex technical and they advise just 4 screws to hold in place and then screw through plasterboard and insulation together with 60mm drywall screws (12mm insul +12.5mm plaster + 36mm into rafter.

I suppose glue would work as its a temporary hold until you fix plasterboard over. Cheaper to use screws though. And maybe a few of these:

http://www.ebay.co.uk/itm/Tile-Back...f9ff5a&pid=100011&rk=1&rkt=12&sd=201803849804

 

[Devonish]

Friction fit the 100mm between your joists then screw insulated plasterboard
to your joists.

I have fitted the 100mm as you describe. Many thanks.

 

[Devonish]

As always, very helpful. Thank you for the advice.