painting over water damaged ceiling

becs

Hi,

We've just had a small leak from our hot water tank which has caused a damp patch on the ceiling below. Obviously I know we will need to let this dry before we can make good the damage but wondered if anyone can advise how long we should leave it and what we should do. The ceiling is a smooth plastered ceiling which was skimmed about a month ago.

Thanks

nickj_2

if the ceiling is still in good condition ,you can seal the damp patch if there's a stain with a damp sealer or some solvent based undercoat the plaster will need to be dry , it shouldn't take more than a few days to dry out , depending on how wet it was if the ceiling is still bare plaster it will all need sealing with a mist coat of thinned matt emulsion , before painting

paintpot

I always use a product called stain stop, you can buy it from most major DIY stores. If you just paint over the stain with emulsion it will keep coming through but this provides a barrier. Don't apply it to unpainted plaster though

library_lass

I've used Stain Stop very successfully, too - it comes in a convenient spray which doesn't easily clog up like other aerosols. However, an experienced decorator told me that you could just as easily (and cheaper) give the area a coat of ordinary undercoat, allowing plenty of time to dry.