Insulated plasterboard - what do I need to consider?

[Artrax]

I am currently redecorating my living room which will involve the whole room being skimmed. I'm considering putting insulated plasterboard on the two external walls.

It's a 60's bungalow with a cavity wall that's been insulated at a later date (loose fill fiberglass type insulation.) Last winter there did seem to be some cold spots in the room on the external walls.

Is it just a case of sticking the boards on the wall with something like pinkgrip dry fix? Is there anything else I should consider before doing this?

Could I hide radiator pipes beind the plasterboard by removing a small vertical channel of the insulation, or would this create problems?

Thanks

 

[^woody^]

The existing plaster would need to be sound and not loose. Remove any wallpaper, paste or emulsion to get good adhesion.

Use some screws to secure the boards.

Yes to the pipe idea.

 

[Artrax]

Thanks Woody.

Is there a special type of fixing required? Other posts on this forum suggest standard frame fixings should be sufficient but in my experience these always sit slightly proud of the surface.

 

[^woody^]

If you have thermalite blocks, you can carefully screw direct into them with a wide thread wood screw, and these will sit flush for skimming

Otherwise some hammerfix type screws, and you'll need to countersink the board.

 

[mrrusty]

Having installed a lot of this recently I suggest use plasterboard (dab) adhesive if the walls are not truly flat as it gives much more scope to knock the boards into position and level with each other. Foam like pinkgrip and instastik work really well when the wall is flat and the insulated PB can be installed tight against it. A few long screws and plugs should be installed - I used just used 100-120mm reissers with brown plugs, but my understanding is this is more of a fire requirement to stop the boards dropping off in a fire.

It's well worth doing - we're living in a 1902 renovation project and it is now an easy house to keep warm.

 

[Artrax]

Thanks. I didn't think that plasterboard adhesive could be used with foil backed insulation (so I had read anyway) but if it's an option I'll definitely consider it.

If I used separate insulation and plasterboard how much more difficult would the installation be? I'm thinking it would be better to do that and tape the joins in the insulation to prevent any moisture getting through, which seems like you can't do with insulated plasterboard... Or is that not a huge concern?

 

[mrrusty]

https://www.siniat.co.uk/en-gb/knowledge-centre/how-to-leaflets/thermal-insulation

 

[phatboy]

Thanks. I didn't think that plasterboard adhesive could be used with foil backed insulation (so I had read anyway) but if it's an option I'll definitely consider it.

It's not an option, but they do boards for dot'n'dab that have a paper back instead of foil.

 

[mrrusty]

It's not an option, but they do boards for dot'n'dab that have a paper back instead of foil.

Best to use the adhesive the manufacturer recommends, in the case of Siniat insulated plasterboard that's their dot and dab adhesive (Universal bonding compound), but foam adhesive does also work well.

 

[catlad]

I was under the impression you couldn't use normal screws for plasterboard as it reacts with the lime in the plaster, also the reason they are phillips.

 

[^woody^]

Plasterboard is gypsum, not lime. As long as the screw is not bare metal - which will cause potential rust staining.