Wallpaper issue - peeling off in the heat.

[Adsibob]

I suspect it’s from the heat, but I noticed today that the wallpaper on a feature wall we have in the loft conversion has peeled off at the edges. It’s even taken a bit of paint off the bit of the adjacent wall where it meets the paper. It was done about 10 weeks ago.

 Not sure what the solution is. Tado tells me that room is currently 36C and given the amount of wood fibre insulation we have, I reckon there is a big decrement delay, such that it will be several hours before we reach peak temperature. Is there Such a thing as heat proof wallpaper paste?

[markc]

Unless the humidity is very high I wouldn’t think paste would be affected by short term heat.

Edited July 19, 2022 by markc

[Adsibob]

1 hour ago, markc said:

Unless the humidity is very high I wouldn’t think paste would be affected by short term heat.

We have MVHR so it can’t be the humidity. Tado tells me humidity varies between 19% and 41% in that room. The paper was actually put up twice. The first time, the installer used too much paste and ended up staining the paper and adjacent walls. Those walls had to be repainted. The second time, he bought new paper and probably used slightly less paste to avoid staining. Maybe he didn’t use enough?

[Marvin]

Either that or the moisture is coming out of the wall... 

[Adsibob]

Update: builder reminded me that this wall was accidentally  painted before being wallpapered. He says best practice is not to paint it and that whilst he lined the wall with lining paper over the painted finish, that didn’t survive the heatwave. (The lining paper came off, the wallpaper remained stuck to the lining paper.)

 

 so what now? surely we don’t need to remove the coat of paint (which I’m fairly sure is just primer)?

[markc]

Can’t see the difference wether lining or top paper, unless the liner paper was low melting point iron on. I have seen sheets of vinyl paint peel off fresh plaster due to no mist coat

[Adsibob]

So there was definitely a mist coat applied to the plaster, then a couple of weeks later they painted it with primer. Then they were about to paint the wall with the actual colour when I said “that’s a mistake, that wall is meant to be wallpapered”. At that point the builder threw his toys out the pram and said “I told you to give me a decoration schedule”. So he is now saying that by that stage it was already too late for optimal wallpapering. Seems odd to me, surely there is a way to wallpaper a painted wall and for it not to peel off in 39C.