bubbles in paint on ceiling (using roller)

[Tom]

Hi, does anyone know what causes this?

I didn't have this problem in my bedrooms and living room, but in my kitchen and bathroom I'm getting it terribly.

I sanded, sugar soaped and primed the ceilings before painting.

Cheers for any tips,

Tom

[Bikini Whacks]

If you're using a large/huge tub of emulsion and you haven't been stirring it then by the time you get towards the bottom you're spreading thick stuff which will hold bubbles with ease. Either thin the mix or do lighter strokes but either way you need more liquidity.

[DIY]

Do you mean that the bubbles form as the vinyl emulsion dries, so that the paint is coming away from the ceiling? If so, and your house is an older property where distemper was used originally to whiten the ceilings, there may still be traces of distemper, even after cleaning, which will not take vinyl emulsion. If this is the problem the usual cure is to seal the surface with a coat of deither diluted PVA bonding agent or a stabilising solution; it is difficult to remove all distemper by washing.