Gloss flaking off/mudcracking on window frame

[Chris]

Hi all,

I've just started to decorate an old room, rubbing down the old gloss on the window frame and sill, and have applied some Dulux water-based gloss. Now -- horror of horrors -- it's coming right off, flaking up off the surface in some areas or simply mudcracking.

What's gone wrong? The tin specified no need for a primer. Could it be that the old (presumably oil-based) gloss won't take the new water- based stuff, even after a swift rub-down? Should I have used some primer before starting with the gloss, even though there was old gloss paint on there?

Please help -- I'm not sure how else to continue at the moment and so could use some of the group wisdom. Thanks.

[James Salisbury]

I have had a similar problem try some undercoat, can't remember if I used water or oil based, one worked one didn't! try oil first, or international paints wood primer. Also use genuine white spirit.

[Pete C]

May be silicone contamination, try googling or a good decorators merchant should be able to advise.

cheers, Pete.

[Chris]

Thanks chaps. I think I might just try and strip off all the paint and start again (if you're going to do a job etc.) as there does seem to be another coat of gloss beneath the coat I'm painting over. It's a Victorian house though, so I'm slightly concerned about dealing with leaded paint if I start going at it with the heat gun. Hopefully I can start again with bare wood, just primed then painted over with the stuff I've bought.

[Chris]

Just to offer an update, I stripped all the paint from the window sill and frame back down to the bare wood, cleaned it, put two coats of Dulux primer/undercoat (water-based) and then another couple of coats of the same gloss on, and still I get cracks and the odd flake coming off.

I can only assume it's something ingrained in the wood that reacts with the water-based paint, as the skirting boards have been fine.

It'll do for the time being -- it's much better than before, but I'll want to redo it before too long, and I'll use some solvent-based liquid gloss on it next time.

[meow2222]

oil based gloss is certainly a far better performer. Water based glosses are, well, just adequate IME.

NT

[Chris]

It would certainly appear so. This is the first time I've tried water- based gloss, and although the drying times and washing up times are greatly reduced, I'm not impressed with the finish compared to other parts of the house painted with oil-based paints.

[Stuart Noble]

IMO ok for exterior woodwork 1st floor and above where it doesn't need to be particularly hardwearing and you don't see the brushmarke etc. It lasts well, such as it is, and keeps its colour better than oil based