# Forum Home Renovation Painting  yellow patches seeping through primer

## blissin

Hello all 
I am painting a tongue and groove ceiling (perhaps oregon pine - orange-ish colour) which is unpainted, along with exposed beams with cross bar supports which are all painted in glossy mission brown 
Decided to paint it off-white after living with it looming over my head for four years - will take a while thanks to it being all rough sawn so lots of lumps and bumps and grooves - ouch, but worth the effort eventually  
I noticed some yellowish patches staining areas painted on previous days - only on the unpainted tongue and groove, not the areas that were painted with mission brown. It seemed to take a day or so to seep through the primer 
I am using solver PSU as the primer - is this okay for unpainted wood? I asked for advice at solvers, but only realised I only mentioned the mission brown, not the unpainted part of the ceiling.  
I am a bit worried that it will do the same after applying the top coat - which was going to be solver ceiling paint. Should I get something different to deal with this issue?  
any advice would be great, thanks

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## r3nov8or

It's likely the yellowing will make it's way through an acrylic top coat. I would use an oil based primer/undercoat. It should lock in the yellowing, but others may have other ideas.

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## blissin

thanks for your reply and the suggestion.  
If I use an oil-based primer, I guess I also need to use an oil-based top-coat?  
I want to have a matte finish on the ceiling - are oil-based top coats available in matte? I always thought they were super-glossy

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## amiaow

Sounds like a tannin bleed from the timber. You can use a stain-blocking prep coat or two (just one example- Dulux Preparation Products- there are many products and lots of people on this forum like Zinsser products) and then your flat acrylic over the top.

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## amiaow

If you've done the whole lot already you could also just try another coat of your Solver product- will probably fix the problem.

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## grantbudd

we used zinnser too on old hardwood skirting and it slowed the leaching of timber but some sections needed up to 6 coats of paint. The internal doors which were varnished and made with dark plywood had to be painted up to 7 coats even after 2 coats of zinnser! All done with a roller and sanded..... 
Go the oil based primer and you can use a water based top coat no problem  :Redface: ) Just a light sand of the primer first. Give it a couple of days to fully dry off and maybe crank up the heat a bit to speed drying times..Go for the most expensive sealing primer that prevents bleeding or leeching problems and do 2 coats of undercoat/primer to be sure...Been there just not painting overhead. Good luck and stay away from advice at bunnings as you will usually get a bum steer  :Redface: )

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## r3nov8or

> thanks for your reply and the suggestion.  
> If I use an oil-based primer, I guess I also need to use an oil-based top-coat?  
> I want to have a matte finish on the ceiling - are oil-based top coats available in matte? I always thought they were super-glossy

   Allow the oil based primer/undercoat to dry really well and top coat with acrylic no problem in my experience.  :Smilie:

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## blissin

great, thanks heaps for all your replies 
It will take me quite a while longer to finish as I can only do it bit by bit after work and the weekends, so I might experiment by re-coating with undercoat on some patches that have yellowed. Then I can just see how it worked by the time I am ready to top coat 
If that is a fail, I will try the oil-based primer option 
I did not know that you could paint over that with anything other than oil-based top coats, so good to hear that acrylic will do it, so I can keep it matte finish 
will re-post my results - might help others with the same issue 
thanks all  :Smilie:

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## JK71

When I was an apprentice they made flat enamel paint we used it on most ceilings after an oil based undercoat, from memory it held all the stains back pretty well. Just not sure if they still sell it as I make signs for a living these days.

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## strangerep

blissin, 
For interior preparation, try Zinsser Bin (red label), which is shellac-based (metho thinner). I've found that it hides better+faster than conventional oil-based undercoats. You can probably do two coats in quick succession with the same roller, since Zinsser Bin is recoatable after an hour or so. But then wait several days to let it cure/shrink before deciding whether to applied a 3rd coat. 
Another trick is to begin with a saturation coat of straight Penetrol -- though this needs 1-2 weeks to cure sufficiently before overcoating. 
(If you decide to try the Zinsser Bin, insist that your paint supplier shakes and stirs the product thoroughly for you, since Zinsser's manufacturing process is such that lots of solids coagulate at the bottom, even with a new batch.)

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## blissin

well, in the end I used two coats of the solver psu primer on the unsealed wood, but just one on the beams, and followed that with a single top coat of tinted solver ceiling paint - all water based.  
Two weeks or so later, I cant see any of the staining, so hopefully that will continue to work. The exposed beams with tongue and groove look heaps better painted all off-white - opens up the whole room and removes all the gloom. Was well worth the effort 
thanks again for all your help

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## simopimo

I like the Solver PSU, I have found it to cover up bleed better than the other water based PSU's. 
Sent from my Xoom using Tapatalk

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## blissin

quick follow-up - six months later, still no bleed so looks like its all good 
cheers,

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## lethaljohn

i know you've fixed the problem, but for anyone else who has the same problem and doesn't want to use a solvent based paint its easiest to use an exterior paint that has tanem block. im pretty sure solver duraguard still has tanem block in it, you just have to give it enough time to cure 100 percent then top coat it with whatever, usually solves the problem. im not much on that solver psu

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