Decorating Advice

[PaulSB]

I need some help with a paint problem as I'm finding different information on the web and in shops I've been to. Our house is a stone-built cottage. When the family grew in size we extended downstairs adding a bathroom, turning the original upstairs bathroom into a bedroom. We left all the plumbing in place and about six months ago changed this bedroom back to a shower room.

Apologies for all the detail but I think it's needed.

There is one outside stone wall, 18" thick, with a full opening window in it. To the touch there doesn't seem to be any temperature difference between this wall and the others. Immediately adjacent to the window we installed a full size walk-in shower with hot water direct from a combi boiler. The walls were re-plastered, it was the original plaster, but not the ceiling as that had been replaced earlier with plasterboard and skimmed. Previously the ceiling had been papered and there was quite a lot of paste residue on the ceiling which I sanded off. I didn't get to do this until after the shower unit had been installed and it was difficult, and I'd had enough, to sand down the ceiling area above the shower as well as the rest of the ceiling.

When it came to painting my wife presented me with a Crown matt emulsion. I had my doubts about the wisdom of using this but there you go. I wanted to use a bathroom formulation but apparently we didn't want a sheen finish!!!!

I now have two areas of paint which are coming off. Above the shower unit the paint has "crazed" with lots of minute cracks - I know this corresponds with the area I didn't sand as well as the rest. Above the window the paint has split in places and can be peeled off in pieces about the size of a dinner plate. The rest of the paint work is perfectly sound. I'm now getting ready to re-paint the whole room with a bathroom paint!!


Question is this. Two different types of peeling in close proximity.

1. I've read that if old wallpaper paste is not fully removed it can cause new paint to craze and crack.
2. For the dinner plate size bits I've read:

paint on new plaster can peel if, the plaster surface is too smooth
has not been "misted" (I assume this means sealed which I did with watered down emulsion)
or is the fact I've used a standard emulsion the problem?

I've stripped back the diner plate sized bits and the surface underneath is very, very smooth so I'm inclined towards this idea.

If I re-sand the area with the crazing above the shower is this enough or do I need to strip the paint off completely which is going to be a pig of a job?

 

[mickle]

You're just going to have to bite the bullet and keep sanding and scraping until it stops falling away. Sorry.

 

[ttcycle]

Yep you want to sand it all off and make sure the surfaces are properly sanded down, let it properly dry out for a few days so you're not sealing the moisture into the wall and get a primer that's designed to work with bathroom waterproofed paints that aren't water soluble. Your best bet is a trade quality paint

 

[threebikesmcginty]

Pay someone else to do it.

 

[dellzeqq]

stabilise it, prime with dilute pva and then tile the sucker.

You can get matte eggshell, by the way - if you use the old-fashioned solvent based stuff it shrugs off wet. But read the label. It will do you in if you breath it.

 

[PaulSB]

Bugger...............looks like tomorrows ride is cancelled.

Thanks for the advice guys.

 

[GM]

What I have done in the past when I've had jobs to do with a similar problem, is to fit moisture resistant plasterboard (normally a green colour) straight onto the old ceiling. You've just got to make sure you know where the joists are. Tape and jointed, then sanded and 2 or 3 coats of Dulux Bathroom Paint.
It's a bit involved, but I think it's worth it in the long run. Good Luck!