Plaster falling off - damp or badly applied?

[Malc]

Hi,

I've just started stripped out a house to redecorate. Walls are papered which has later been paint. The top, finish coat of the plaster is coming off. So far on the 2 half walls that have been stripped, about 90% has come off. Pull the paper seems to pull the plaster off most times. Streaming difficult bits often causes the plaster to blow. Finish plaster coat is quite thin 2-3mm, sometimes less. In one case the electric cable plastic conduit is level with the undercoat with only the finish plaster over it.

House was built in 1986 so cavity wall with cavity half filled. Later cavity wall filling was inserted (pilkinton superfil rock fibre).

Could this be damp? Or was it is just a rubbish job, bad plaster, undercoat too dry?

 

[PrenticeBoyofDerry]

It is not uncommon that plaster finish comes of when stripping paper, likely original plaster, would be very difficult to say whether it had been applied correctly or not, do you have damp issues?

Also over heating plaster via wallpaper stripper will blow plaster.

It is a common thing to find failing plaster to be covered with wallpaper.

 

[xr4x4]

Was the plaster painted before wallpapered, or was the wallpaper put on the unpainted plaster ?

 

[Malc]

I can't see any sign of paint so I would say it wasn't painted before being papered.

My house has some plastered walls (this is my mother's). Stripping paper off those has never pulled off all the top plaster back to undercoat plaster.

I don't think the walls are damp. Bit of sign of mould in the corner but that was an outside wall with a bank of wardrobes in front so I'm not surprise about that. This was in the corners. No sign of damp elsewhere and no sign on the open (nothing in front of it) wall.

I think the thistle coat in my house is thicker though. In places this is barely covering the undercoat plaster.

 

[xr4x4]

Wallpaper paste sticks like sh!t to fresh plaster.

 

[ree]

As above respondents.

If you do have to knock off a patch of plaster then why not remove a brick or two, and examine the condition of the cavity insulation?

 

[Malc]

The undercoat is fine so it would be a bit of job to take a brick out (would be a block anyway). I don't think it is damp I think it was just poor plaster.

I'm stripping other plastered walls in the same house and not having these issues. The plaster blows with the steam on it for say 10s in some cases. Some places are stuck firm but even there with say 15s of steam the plaster becomes quite soft and is easily carved with a scrapper. Also some plaster is coming off which has had no steam on it.