We had the lounge plastered last week and a small spot has cracked/blown, about the size of a loaf of bread. Any idea on the best ways to fix such a thing before I can get the painting started? I’ve asked the plasterer but he’s not got back to me as yet. It wasn’t his fault either so he’s under no obligation to come and repair it.

I’m curious as to whether an off the shelf filler type product will do the job if sanded down properly afterwards. As my local Wickes/B & Q are very unlikely to have knowledgable staff (based upon previous experiences) I thought I’d take a punt in here. It’s on a chimney breast if that matters, above a log burner.

hack it off and just get some one coat plaster – two coats if it’s a thick layer – it’ll be easy to match level/height with the existing plaster with such a small patch – just use a piece of wood as a straight edge to check.

It wasn’t his fault either so he’s under no obligation to come and repair it.

Why, what did you do? 😀

Hack it all off and start again with patching plaster on that bit.  You can DIY it but I’ve never got a finish I’d be happy to paint on, only wallpaper which I guess probably isn’t the plan above the stove?

I’d get the plasterer back and either hope he’ll fix it (unless you did something silly like light the woodburner before it was completely dry), or pay him to re-do that section.

No way to repair, as above, chop out the blown bits. Mix a solution of PVA, apply to the substrate and especially to the edge between plaster and wall. This will help to bond the new plaster and also help to avoid any further blow off. Do not get any PVA mix on the face of the new plaster or it will show through when you decorate. Get a small bag of plaster and skim over, as above.

unless you did something silly like light the woodburner before it was completely dry

Yep. Wasn’t as dry as we thought it was. Thought it would be OK to just gently add some extra warmth to the lounge with 2 small logs but definitely not.

you can buy readymix plaster from screwfix for about 12 quid which makes life easier. I’ve plastered some pretty big areas using it, and quite thick depth (1.5cm ish). Just build it up in layers. Ideally you want to plaster slightly thicker than the remaining plaster and then sand down to smooth, as it’s unlikely you will get a smooth finish otherwise.

In terms of actually applying the plaster, a wallpaper scraper or something else flat does the job.

Also, if you paint with a roller then the texture this gives will cover any slight differences.

Ok cheers, that’s very helpful. Bit annoyed about it if I’m honest as it looked fine but turns out to not be the case. The stove was on about as low as it could go, so no more heat than you’d get off a rad.

you can buy readymix plaster from screwfix for about 12 quid

The readymix stuff isn’t “plaster”, plaster is cementitious (I think that’s the right word) it reacts with water to set hard (like cement, or lime mortar), the ready mixed stuff sets by evaporation so can only be applied in thin layers.

Get a small bag of plaster and skim over, as above

*FINISHING PLASTER* 😉

But as above, I have used the ready-mixed stuff and made an almost invisible fix.

If you patch it, chances are you’ll always see it especially above a stove as your always looking at it. Wants doing again. Was it a reskim or onto boards? How long did you leave it?

It was left 4 days. The plasterer has got back in touch and is going to head over and check it out. Most of the area it’s on will be hidden behind the oak effect beam we’re going to stick on the wall. He’s worried it’s affected some of the stuff behind the plaster which I rather hope hasn’t happened.

It was a new stove install so some of the chimney breast has been bricked up after the previous gas fire was removed. It’s only in a small spot about A4 size though so I’m hopeful it hasn’t knackered it.

Your problem now is going to be that, with differential expansion, the edges of the repair will soon crack and it will always be visible. Guess how I know this?  The plaster for a few feet around a fireplace needs to be one single application otherwise cracks will appear.

Our plasterer asked us to leave our new plasterwork at least 2 weeks before painting and preferably with no heating on.

Starting a fire in 4 days was madness.

The problem is that the blown bit is probably only part of what is affected now. You could find bits dropping off later on as the heat has affected the bond between the new plaster and the substrate. Much the same as if you don’t prep with PVA on high suction areas – the moisture has gone so the bond might be affected.

If it was me I’d take the chimney breast plaster off and re do it, I would know for sure it was ok then.

Personally,  I’d light the log burner  and get it as hot as you can and see if it affects the rest of the  wall. There’s no point  patching the live plaster  if it happens again in a different place  If it was me plastering it, i would  hack off a bigger area  and dot &dab  a fireline plasterboard to the brickwork  . PVA  the remaining part it the  wall and reskim it so it all looks the same

Starting a fire in 4 days was madness.

Hindsight and all that and in fairness the plasterers never told us to not use it and the stove installer said no big fires in the first 24 hours of having it. So we lit about the smallest one we could (it was cool enough that you could keep your hand on the stove top) to help cure the stove, as it says you should do in the manual and as the installer said to do after a day of having it. So yeah whilst not the smartest move we weren’t really aware of it being such a bad one at the time.

Anyway, seems that even that has had an adverse effect. It is only a very small patch though so I’m hopeful it won’t all have to be done again. Guess we’ll find out tomorrow.

If your patching plaster make sure you thoughlly soak the edges of the good plaster or you will get cracking. This was the biggest tip i got from a plastering course i did. A straight edge will help.

“Most of the area it’s on will be hidden behind the oak effect beam we’re going to stick on the wall”

Add some feature artex?

for a paying customer i would be having a good hack at it and seeing how much more comes of, blown plaster usually spreads further than you think once you start, and checking the rest of the wall for hollow sounds and then patch it up.

my own house i’d get the easifill out as long as it was just the skim.

I’ve patched n painted before

Avoid straight lines the eyes pick up on them.

Plaster flush n then when finishing use the fat or the cream with to paint the edges using a paint brush. Let it dry then light sanding of the repair

I’m pretty sure it’s just the skim as I can’t stop tapping it. We had lots of other areas of blown plaster in the house so I’m familiar with what it’s like when bad.