stain blocking products

[Jonbdiy]

Hi, so we have a water stain on our bedroom ceiling caused by a roof issue which is now sorted, the roof was fixed 3 weeks ago.

I want to paint over the water stain but i'm worried if i use stain blocking sprays etc and then paint it will show on the ceiling, re-painting the whole ceiling isn't an option, the room was newly decorate just 3 months ago.

if i cleaned the stain with a bleach / water mix so the brown fades and then paint over that should sort it?

thanks

 

[JohnD]

use a brush, not a spray. The spray will blow around the room.

If the ceiling was only painted a few months ago, use the same brand of paint once the blocker is fully dry.

Once you have repainted the stains, you can brush a thinned coat out towards the old paint on the rest of the ceiling to fade it in, or use a roller, which will replicate the texture.

Nobody except you will notice it, provided you hide your wife's glasses.

Choose a lampshade that throws the light downwards rather than up.

 

[Jonbdiy]

ok thanks, what if i used the bleach and water method to remove most of the brown stain and then paint over with the white dulux?

 

[Chivas69]

I don't think you'll remove a water stain with bleach. You can wipe off the excess but you'll still need a stain block on it.
Like said above, put on blocker. Let it dry then blend in some of the exact same emulsion, preferably with a roller. If it's not too big a patch you can get away with a sponge, dabbing it with paint over the area!

 

[Jonbdiy]

Thanks for the replies

I’m worried about using certain stain blockers because I’ve read they “flash” through when painted over, my ceiling is plain dulux Matt and was painted just a few months ago, I’d really like to be able to block the stain and use the dulux over that without a trace of any stain / flashing from the stain blocker.

would this work, it’s Matt so would that be better?
https://www.screwfix.com/p/no-nonse...ml/57548#product_additional_details_container

 

[Chivas69]

Yes but if you're going to constantly look at it knowing it's there you'll be better or doing the whole ceiling again. More because you'll likely see faint roller marks

 

[sparkwright]

I have found that patching a ceiling with stain-blocker, then emulsioning over the patch, DOES causing flashing - but have also noticed the flashing can disappear in about a week as it cures properly.

Water-based stain blockers and the like are available, may be worth a try.

 

[Chivas69]

Actually, that stain blocker you posted above is not suitable for water stains. That's more for nicotine or graffiti etc.
You need one like zinsser. Again, if it's not too big you could use some oil based undercoat if you have some lying around in the shed.

 

[Jonbdiy]

Actually, that stain blocker you posted above is not suitable for water stains. That's more for nicotine or graffiti etc.
You need one like zinsser. Again, if it's not too big you could use some oil based undercoat if you have some lying around in the shed.

it says not suitable for water stains unless the cause of the stain has been fixed and the area allowed to dry, the roof has been fixed three weeks ago and the plaster is bone dry, do you think this would be suitable as it’s Matt and shouldn’t flash through ?

 

[Jonbdiy]

the zinsser cover stain looks decent also, i might use that

so if i use the zinsser over the stain then use the dulux white matt over that will it blend in the the rest of the ceiling or will i have a patch?

 

[sparkwright]

Chances are you will see a patch of some sort.

You say it is out of the question to re-paint the whole ceiling as the room was decorated recently.

It is usually possible to re-paint a ceiling without messing up the rest of the room, so can it be done?

 

[Jonbdiy]

yeah i can't be bothered with painting the whole ceiling again, the room is all set up just how we like it apart from this patch that appeared literally one week after the bedroom was finished, the roof is fixed £1500 later so if i can avoid any more stress i will lol.

so no matter how many coats of dulux matt i put on that patch its gonna keep showing, i put two on last night and its lighter than it was, is it 100% certain even if i put 15 coats over it its gonna come through because id rather attempt that and not have a stain block patch and or have to re-paint the whole ceilling.

 

[sparkwright]

You can put 100 coats of emulsion over a dry damp stain, and it will still show. They always do.

You need a suitable stainblock.

 

[Jonbdiy]

ok i'm just going to try the zinsser and see what happens

thanks

 

[sparkwright]

When I had to touch up a dry damp stain, I used Dulux Damp Seal primer and undercoat. It is water-based. It is suitable for dry and wet stains.

I used it because, like you, I was worried an oil-based primer would show through the emulsion.

I used two coats of this quick drying product, and it worked very well, and there was no evidence of this primer showing through the emulsion.