Coving Joints - Hairline Cracks! Help!

[rossbardon]

Hi,

I am having a nightmare and need some advice. I had my dinning room replastered. Poor plastering job to be honest. The walls are not very level, so when I fitted my coving (covemaster, polystyrene paper wrapped coving) I had to use large amounts of adhesive to fill the varying gap sizes between the walls/ceiling and the coving. Coving went up ok, and it looks fine, but as the adhesive has dried small hairline cracks have appeared on some of the joints. This maybe due to the large amount of adhesive? or maybe the coving adhesive I have used is faulty?

Anyway, my requirement is I needed to get rid of these hairline cracks. I Chaulked and then painted with emulsion. It looks like the chaulk has worked well, but then the emulsion I am using (crown matt) cracks on the chaulk! I read the solution was to use an oil based undercoat first then emulsion. I tried this but still had some very small cracks (the undercoat was crown performance series undercoat).

What is going wrong, is my main problem I am using crown emulsion? Is it rubbish stuff?

What paint can I use on the chaulk (soudall, B&Q) which will not crack and I also need to be able to use the paint on the ceiling, coving too (so the colour is the same). What about the polycell flexible ceiling paint?

Thanks in advance.

 

[misterhelpful]

This is a pretty common occurrence with matt emulsion, but if it is just the paint that is cracking and you have used oil based undercoat, it should have solved the problem.

The only thing I can think of is that the caulk is a bit thick and is still drying out, which it does as a different rate to paint, and it has been painted too soon, causing the paint to crack. Caulks usually say paintable in 1 hour, but very rarely can this be done if it is applied thickly.

If this isn't the cause, you could try the flexible ceiling paint but be aware that it is thicker than standard emulsion and may make the finish look uneven if only used on the cracks.

 

[rossbardon]

I think I will give the flexible ceiling paint a go. I was going to go with the polycell crack free ceiling paint? Is this ok? Or would you recommend another flexible ceiling paint?

 

[misterhelpful]

It's what I have used on the odd occasion I've come across nuisance cracks, but I'm not keen on it, and usually manage to solve the problems with fillers, caulks and oil based paints.
Your situation does seem a little unusual, seeing as you have already tried these, so perhaps the Polycell is the way to go.