Help! Painted new plaster, have a crack!

ITtim

Hi All,

So we had our ceiling re-skimmed last week, was done on Tuesday, the Plasterer said that it should turn salmony pink by the weekend and if it does we could paint it.

So on Saturday I went to screwfix and purchased their very well reviewed 'new plaster paint' I gather it doesnt contain vinyl so the plaster can breath. Anyway, i put a coat on. This morning i've noticed a hairline crack from one end of the room to another.

So what do i do?

I guess I could either second coat it now and hope the crack gets covered up

I could second coat it next weekend and hope that the plaster is better prepared to take the paint.

I could purchase the polycell ceiling paint which does an ok job of hiding small cracks (but i fear this will prevent the plaster breathing)

Does anyone have anything to suggest? I'm keen to get the second coat on but not at the risk of damaging the plaster. Any help appreciated

Kiran

It's just a shrinkage crack. If it's hairline you could probably just paint over it however if you want to fill it use something like Easi Fil as you'll be able to sand it back perfectly smooth and it only takes and hour or so before you can paint the ceing to a finish

roddydogs

I dont understand the Screwfix stuff, the first coat on new plaster should be a "Mist" ie thinned down coat. So it cant really be used as a top coat.

ITtim

roddydogs wrote: »

I dont understand the Screwfix stuff, the first coat on new plaster should be a "Mist" ie thinned down coat. So it cant really be used as a top coat.

My understanding is that the watered down mist coat is to limit the amount of vinyl in the paint, the screwfix stuff doesnt have any in it.

ITtim

Kiran wrote: »

It's just a shrinkage crack. If it's hairline you could probably just paint over it however if you want to fill it use something like Easi Fil as you'll be able to sand it back perfectly smooth and it only takes and hour or so before you can paint the ceing to a finish

Thanks Kiran, would that maybe explain why sometimes i can't see the crack?

roddydogs

ITtim wrote: »

My understanding is that the watered down mist coat is to limit the amount of vinyl in the paint, the screwfix stuff doesnt have any in it.

Yes, but trade matt dosent either, but you still supposed to thin the first coat.

ITtim

ah ok, didn't know that, there seems to be so much contradicting information. I bought the screwfix stuff based on a recommendation and the excellent reviews it seems to get

roddydogs

It may well be excellent, im not knocking it. Someone else will probably post you should have put PVA on the bare plaster.

DTDfanBoy

ITtim wrote: »

My understanding is that the watered down mist coat is to limit the amount of vinyl in the paint, the screwfix stuff doesnt have any in it.

New plaster is incredibly absorbent, splash some water on it and it'll be sucked straight into the plaster, the same thing will happen when you paint the wall for the first time, more water in the paint means that more water is left in the paint when it hits the wall.

Don't use PVA it will only make things worse

ITtim

DTDfanBoy wrote: »

New plaster is incredibly absorbent, splash some water on it and it'll be sucked straight into the plaster, the same thing will happen when you paint the wall for the first time, more water in the paint means that more water is left in the paint when it hits the wall.

Don't use PVA it will only make things worse

Is it too late to add water or should i just go with the second coat?

Furts

Paint for new plaster, obliterating emulsion, high opacity...whatever one calls it the paint contains a high percentage of filler - probably chalk, or China Clay, but I am not a chemist. The product is meant to fill dimples, air holes, imperfections, shrinkage cracks - it is formulated for this purpose as well as to allow the plaster to dry out through it.

So I would put another coat on the ceiling, assuming of course that your plasterer has not cut corners and caused the problem. It may be valid to ask were there area of damage, or board joints, requiring scrim to be applied before scimming the ceiling? If so, did the plasterer do this?