Mushroom Plugs or Bonding for Plasterboard

CBYR1983

Another simple one - should I insist on bonding and minimal use of mushroom plugs or are plugs ok for attaching 38mm insulated plasterboard to solid concrete walls.

My concerns are regarding cold bridging and plaster "pops".

mp22

Bonding with mushrooms at the edges of the boards.(where it thins down)

CBYR1983

My thoughts exactly - but I've spoken to a few plasterers and they just want to use the plugs.

Is it just because it is easier - are they ignoring the issues?

mp22

Its generally quicker to just use the mushrooms.

nophd08

Good fitters will use both plugs and bonding.
Its generally recommended that you use only 3 plugs after bonding has gone off.
Bonding also allows sheet to be set perfectly plumb both ways.
I done my own walls with both although using only plugs is not wrong its just bad workmanship.

CBYR1983

nophd08 wrote: »

Good fitters will use both plugs and bonding.
Its generally recommended that you use only 3 plugs after bonding has gone off.
Bonding also allows sheet to be set perfectly plumb both ways.
I done my own walls with both although using only plugs is not wrong its just bad workmanship.

Well I couldn't believe the way they did it. About 10 plugs per board, in and out all over the place. Not to mention the number of holes that were left where they had to re-bore. There must be thirty or so extra holes!

I would never have thought that a plasterer would be able to go anywhere near a wall like the way they've thrown it up. I'd be embarrassed to present it as my own work, and I work in an office.

They're skimming the walls today so I'm hoping they'll finish it off ok but my confidence in them is shot - I wouldn't mind - the same guy did a lovely job of a re-skim for me a few years back. I thought the walls were bad then.

Maybe I should reserve judgement until I've seen it skimmed but to me those mushrooms are a disaster.

Does anyone know if this overall insulated plasterboard method is better or worse than old-style studs and blanket in between covered in standard plasterboard. If I was doing it myself I'd do it that way simply because it would be easier for me.

I know the studs bridge the cold but surely the plugs do as well.

ronaldo84

did they use plastic or metal murshroom fixings?? bonding would be useful if the walls are uneven and not plumb i would use 3 or 4 in the centre of da board and 3 or 4 down the tapered joints to hold both boards countersink them with the hammer and fill with joint filler and scrim tape. even if it looked a bit rough a good plaster could make a good job of it the most important thing is to get the wall flat and reasonably plumb

nophd08

I think they were a bit plug happy but i'm sure plasterer will cover all dodgy work. Did they use scrim cloth on joints, ( a mesh type tape ) it will help prevent cracking.
Insulated board is a better method than battens and seperate insulation and will be a good job when all is finished. Make sure you are 100% happy before parting with any payment.
Check around all windows, sockets etc.
Might be a good idea to hold back a few euro until plaster drys out, then you will get a good look at finish and if you are not happy....MONEY TALKS

CBYR1983

Thanks Lads,

I was much happier once I had seen it skimmed. It looks quite good. There is one particular horizontal joint where the skim had to be quite thin because the two boards were far from plumb, I can see the tape a bit but it shouldn't be visible once painted, I hope. From side view it looks flat.

Yeah, they used self-adhesive scrim to tape the joints.

In fairness, yer man can skim really well - I was shocked at how well it looked despite the boards being the way they were.

Tuesday was a very wet day as well so that wouldn't have helped - I imagine by the end they were having to cut the boards inside standing up- - they were only 38mm boards so they probably just used stanley instead of a saw - rougher edges and so on.

Hopefully the insulated boards will make a good job of it - I suppose the small gaps they skimmed over shouldn't be that bad for loss of heat, though I would have been a lot happier it they had been really snug and neat.

By the way, it was along a staircase, coupled with a curved ceiling, so a good bit of board cutting involved, but even still I expected experienced people to be more precise in their board cutting, I couldn't really recommend them for dry-lining on that basis, no problem on a re-skim, and I suppose they have to be relying on recommendations with the way things are now.

I'm glad I couldn't afford external insulation - if I was mad enough to part with 10k and there were gaps I'd be absolutely livid.