Sealing A Water Stain

[derekpara]

Will PVA sealant seal a water stained ceiling prior to applying emulsion paint ?

Cheers.

d

[The Builder]

If the stain is particularly bad, Derek, it could easily reappear.
A couple of coats of diluted PVA (3 water to 1 PVA) might hold it.

Traditionally, oil-based undercoat has been the favourite. Also, aluminium paint can block even tar paints.

[KARL]

I always paint over it with an oil based paint, as much as two coats - that has always worked. the trouble with PVA is that it is not impervious to water.

[Prudie]

I've had a bad stain like this and tried quite a few things (stainstop etc) but it always seeped through. Finally cured it with 2 coats of white gloss before emulsioning over.

[rockyracoon]

I'm glad someone has asked this, my brother has just moved into a new flat and there's a bug patch of oil stain behind where the cooker had been, I was going to tell him to buy a stain sealer, but undercoat might be cheaper.

[derekpara]

Thanks everyone. Oil based treatment it will be.

D

[theshedman]

I always use a mixture of oil based undercoat and gloss around 50-50. The gloss seals better than the undercoat alone and the undercoat makes it easier for the new emulsion to adhere to. Just make sure that you have good ventilation especially if you are using it over large area.

[derekpara]

Thanks Shedman.

D