Painting nightmare! Please help!

[sparkwright]

Any PVA used? (there shouldn't have been)

How was the mist coat diluted?

Can you send photos?

Will it all scrape off easily?

 

[nic d46]

Hi
No we didn't use pva. The paint was diluted but 10% as the instructions said. I can't get pics right now but will try tomorrow. Yes scrapes off easily where the patches are. I've read on another page that an oil based primer may help? what would be your thoughts on this? Thanks

 

[misterhelpful]

It's unusual for contract matt to actually 'peel' off so I think sparkwright is on the right lines with PVA. This could have been used during plastering and has got onto the finished surface or the plaster may have been over-polished in some patches which will make the surface too shiny for paint to adhere to properly.

 

[nic d46]

Hi again
Would you suggest sanding the areas or trying a primer? Would you have any suggestions how to get the best/most even finish without having to remove all of the paint? Thank you both for your help it's really appreciated

 

[misterhelpful]

A light sand of the problem areas with 180 or 220 grit paper should help adhesion issues, unless there is PVA involved. Any coarser than that will damage the plaster surface and may leave noticeable scratches that show through the paint. A high grip primer might help if you do have a PVA problem.

 

[Chud]

10% doesn't sound very diluted for a mist coat - it's 40% for crown covermatt and I think it may be 50% for Dulux supermatt?

So...are you sure you diluted the mist coat enough as 10% sounds more like what you could thin it by for normal use?

Secondly how long did you leave between the mist coat and first 'proper' coat - drying time and recoat time are normally different - the recoat time can be quite a bit longer? [edit] I've read in a few places you should allow 24 hrs between mist and first coat.

 

[nic d46]

Hi the paint we bought said 10%. It was designed for new plaster. It was more than 24hours a few days

 

[Chud]

I've had a look at that paint - I think it's B&Q own brand so not really a proper trade paint.

I'd be inclined to take back to B&Q for a refund (not fit for purpose etc) and get some dulux supermatt to replace it. If you've got a problem with the ceiling/contamination etc then you'll still have to deal with it but if it's a paint issue then that should sort it.

 

[Chud]

If you do change paint then I'd apply another mist coat at least in the areas where it's peeled off.

 

[nic d46]

Hi again. I've spoken to someone who uses the paint on a regular basis and he's had no issues on fresh plaster. Our plasterer told us we didn't even need a mist coat but we thought we were playing it safe by buying that type of paint and still adding the amount of water stated. Ahh it's so frustrating! Thank you all for your advice will take it all on board and devise a plan of action! Will update later! Thanks again all your input is appreciated

 

[dcdec]

If you don't find another way, you could apply a couple a coat or two of zinnser gardz, this will seal it completely. It is an expensive option unfortunately, but will solve the problem. Sounds like the paint has failed if you're absolutely sure the plaster was dry, if not, paint will not adhere to wet plaster.

 

[Chud]

Hi again. I've spoken to someone who uses the paint on a regular basis and he's had no issues on fresh plaster. Our plasterer told us we didn't even need a mist coat but we thought we were playing it safe by buying that type of paint and still adding the amount of water stated. Ahh it's so frustrating! Thank you all for your advice will take it all on board and devise a plan of action! Will update later! Thanks again all your input is appreciated

Reviews on it seem quite mixed with quite a few folk having experienced issues not that dissimilar to you.

 

[nic d46]

Hi just an update. I spoke to a different plasterer on the phone and he offered to come look at it and now been told the likely problem is that the plaster wasn't trowelled properly. He's suggested we could try sealing it or have it re -done. Might try to seal a patch and see what happens but I'm not overly confident with diy and figured if it's a fault with the plaster I could end up forking out A lot of money trying to remedy the flaws then possibly still need to have it skimmed? Many thanks for the help and suggestions it's great to see the support available on here. I'm going to take the concerns with the paint on board too and change it in case it is a contributing factor. Thanks all

 

[amfisted]

Perhaps not exactly the same issue as yours, but I had the Devil's own job making good the surface of a bedroom ceiling about six months after moving into this house.

I had decided to repair a plasterboard crack but did it badly, and my first (and incorrect) instinct was to try to blend my bad repair into the rest of the ceiling using textured paint. I applied the textured paint and to my horror, the ceiling came out in blisters. I can only assume that what caused this was some sort of chemical reaction between the textured paint the paint used on the original surface, and I ended up, despite having very little plastering experience, scraping off the old paint and the skim coat it was attached to, and applying a new skim coat so that I could start to make good the surface from scratch.
Finished up with a half decent job, to my amazement.

 

[Jockstrap]

M8 why don't u just get painter in I know if it wiz me I'd want £100 to paint 3coats &£50 to fix u & plasters mess I would bring my drywall dustless electric sanding machine to make it smooth