Can you plaster on top of paint ?

Have you not got diffrent levels?

 

sure can.

 

Hi Yanni.

As above, what are differences in levels ? 'Multifinish' is only suitable for a skim, I believe (tho' I have applied it pretty thick in the past in cases like yours!)

There are alternative 'plasters' which allow greater thickness's to be used.

Anyways, if you set up your corner beads and give the walls two coats of PVA - one slightly thinned and t'other neat - and allow both to fully dry (really - much 'safer' that way; nothing worse than trying to apply plaster onto too-wet PVA), then your plaster should go on nicely.

 

If possible, it'll be worth filling them up to the rest of the level, as otherwise, when you are ready to finish, your levels will dry out at different times, so you will find it more dificult to smooth(ie your deeper bit may still be too wet when the other is ready).


Mr. Handyandy - really

 

I hate to disagree with Mr Ha (really) but it's a close call.

4mm isn't really that thick, and you should get away with it no problem - it would be a fair bit more work to fill in these deeper parts separately. The 'drying at different times' bit doesn't really apply as plaster sets chemically rather than dry out - the drying out part happens afterwards, after the finishing/polishing has been done. It should set at pretty much the same rate.

However, if you do decide to 'fill in' first, then add a further coat of PVA on top of this afterwards, or else it'll draw water out off your skim and it'll feel completely different to the rest of the surface.

The purpose of the PVA is to seal the surface, make the skim adhere properly, and to 'balance out' the whole surface so that the skim goes on similarly all over - not patchy.

 

I don't like to argue back(much) wuth DA, but I do feel there's a big difference between the drying times of say a 2-3mm skim and a 6-7mm fill/skim.

And the drying out(chemically or otherwise) IS drying out(the absorbtion of the water additive into the wall or atmosphere goes to prove it), and the polishing/finishing is done BEFORE it dries out(otherwise you're knacked).



Mr. Handyandy - really

 

I agree with DA on this one, the best bet would be to PVA twice etc etc, the mix up and throw a bit in, this would be ideal if you were doing 2 walls and only 1 had a few holes in.

 

complete **** 4 mm is nothing skim beads are 3mm so a extra 1mm is neither here nor there. pva it the night before and then about 10 mins before your going to skim it still tacky but not dry.

 

But it's not 4mm.

It's 4mm + the 3mm skim of the rest of the level.


7mm of plaster in patches, but 3mm of plaster throughout.

Look at it between your finger and thumb.



Mr. Handyandy - really

 

Fair 'nuff - 7mm is getting thick for 'multifinish', especially if it's on a non-porous surface such as one that's been PVA'd.

It can be done, tho' - it really depends on how large the deeper areas are - if it's the odd patch, then no probs. Larger areas and it could 'slump' a little, tho' you can sort this as the plaster begins to set.

Also there are alternative plaster products designed for thicker application.

Or fill first, and skim after...