Which plasterboard do I want?

[mr noble]

I plan to put some insulated plasterboard on the Garage side of the wall between the garage and the house because the two rooms on that wall are noticeably colder than all the other rooms in the house.

Hopefully something like a 50mm insulation board stuck to a 12.5mm plasterboard will make a decent difference next winter.

I’ve two questions....


1) Will there be any real difference between the cheapest Gyproc board at £25 and the top of the range Knauff board at £70? (I’ll need 6 or 7 boards)

2) Do I need “tapered edge” or “straight edge”?

I intend to stick them straight onto the breeze block garage wall with Something like pink grip Adhesive and then mastik around the edges. But I’m not sure what to do with the joins. Do I get tapered edge and attempt to plaster the tapered bits flush and then paint the whole wall, or is it easier to get square edge and fill the joins with polyfiller??

Many thanks for any help and suggestions.

[cman]

Whilst you wait for the experts to come along (I am not one!) this may help...

Celotex PL4000: https://www.celotex.co.uk/assets/pl4...heet_nov18.pdf



The guide does include direct to breeze block install, as well as how to address the joins...

[manganr]

Get tapered edge and fill and sand down with Easi-Fill TWICE for invisible joints. Square edge are for a plastering finish.

[lewie]

Why don’t you stud out the wall and insulate it with some Rockwall roll insulation then you can screw the board to the studwork
You could just ply over the studwork rather than plasterboard

[eagletower]

I used 25mm insulation with 12mm plasterboard so total of 37mm. Made a huge difference. When I was researching this I was advised this would be sufficient and it follows the law of diminishing returns eg 100mm insulation won’t give you 4 times the effect of 25mm infact the benefit was minimal. You can check U values when ordering so if space is important go with a thinner board .

[mr noble]

That’s ace, thanks guys. Very helpful video.

And the tapered edge is clearly the one to go for.

Thank you TZ folk.

[ejtrent]

Tapered edge for tape jointing + easifill the gaps (ensure you actually orient the tapered edges correctly when installing). Square edge for skimming over the top of by a plastered.

Tapered edge/tape jointing far slower and more work as you do a lot of sanding but arguably a more consistent result especially for a non plasterer.

Square edge is if you have a plasterer who will just multi finish over the lot.

[yumma]

Another quick tip, as well as Celotex use foil backed plasterboard as this will also help reflect heat and act as a vapour control layer.