Bathroom paint failing over J/C

This is very close to the problem recently discussed in this thread, but I have some questions.

I did some drywall repair, and put down a skim coat on some areas where the drywall was messed up. I wet spunged and let dry, and primed with Zinsser 123. This was over a previous latex layer and the J/C from the repairs and skiming.

The paint is pealing off in huge sheets wherever the J/C was used, but seems to be holding well to the previous latex coat (at least, for now).

1) How can I effectively remove the fresh paint from the J/C areas and blend into the areas that are adhering well?

2) I've heard of GARDZ as a solution for this. Is that a good idea, or is another primer a better match.

3) Should I prime over everything, or just the J/C areas?

Thanks.

 

Welcome to the forums!

Is just the paint/primer peeling or is the j/c coming off with it?
How old is your house?

 

It comes off the J/C very easily, and the J/C comes off on my finger by just drawing over it. The primer and top coat both pealed off. The pealing stops when the primer is covering the previous paint rather than the J/C. I wet sanded after dry sanding, and thought I had removed the dust, but it appears that the J/C I used remains the consistency of chalk.

The house was built in the 70s, and that's how hold these walls are (at least, from the look of the drywall). It's been painted several times since then, and recently by the previous owner (probably within the last year). No problem at all with the previous paint since we've lived here (since April, '08).

Thanks for the reply!

 

Dry joint compound shouldn't be chalky.
It is hard to say if your bath was originally painted with oil base or latex but since the primer has adhered to the previous paint - we can rule that out. That pretty much leaves the j/c at fault.

There is no need to wet sand j/c [I don't know if that contributed to the problem] Generally sanding with 120-180 grit is sufficent. Dusting with a dry or damp rag should be plenty good enough to remove any sanding dust.

 

Actually what you are experiencing is very common with paint and primer over joint compound - the only difference is not everyone gets to experience it like you did. People would be surprised to know how poorly drywall primer adheres to drywall mud. It really doesn't stick at all.

What I would do is this (without seeing it).

1) Peel back the worst areas and sand any rough edges.
2) apply Gardz to all of it.
3) patch your areas again
4) apply Gardz over the patches

Dont worry about the white chalkiness over the mud, (Gardz will fix that) that is always the case. You can wash it, wipe it, vac it, clean it any way you want and when its dry, it will chalk on your finger again. Nature of the beast.
Then paint as usual.