Drip marks on new plaster

[BATTLESTAR007]

I've just had a garage converted to play room with new plaster board etc. I have waited for the the plaster to dry and then have covered the paint with a watered down white emulsion paint. To my horror it's covered in what appear to be drip marks! These are virtually everywhere (except not in the ceiling bizarrely) and are slight indentations in the plaster. I have tested a small area of the wall and covered it with 8 coats of paint various mixtures and colours. The marks are still there. This surely can't be normal can it? I've seen suggestions to sand down the walls but again this can't be right can it I will be thee forever! I have also read it might be a PVA issue whatever that is. Any advice would be appreciated. One final thing I haven't paid the builder yet as I'm not happy with the plaster. Is this ethical or is it normal for these marks to appear? I'm confused......

 

[Alastairreid]

The only thing i can think of is splashes of pva but what was he using the pva for.

//www.diynot.com/forums/viewtopic.php?t=226419&start=0

 

[BATTLESTAR007]

Do you not have to cover the original
Plaster with PVA before skimming? Another builder said this is what some do and he may have used a dirty brush to put it in with?

 

[Alastairreid]

Not on top of new plasterboard.

 

[Tozzy]

Are you sure they are drip marks and simply not areas which haven't been adequately polished up during the trowelling stages? If not, all i can think of is sealing the area multiple times with PVA 1:5, letting each coat fully dry before applying the next and try painting again?

 

[ree]

OP, why dont you save a lot of guessing and post pics - of whole areas and detailed close-ups?

As above, there's no sense in PVA'ing raw plaster board. But if they did then perhaps they did it wrong? Or, perhaps the PVA had been in the van too long or wrong proportions etc?

Even if the wet brush had not been washed clean of any PVA before being used for skimming its doubtful that it would have continued to streak for the whole room skim?

Tozzy,
Everything that you've just suggested is wrong.

 

[NickB_99]

I've just had a garage converted to play room with new plaster board etc. I have waited for the the plaster to dry and then have covered the paint with a watered down white emulsion paint. To my horror it's covered in what appear to be drip marks! These are virtually everywhere (except not in the ceiling bizarrely)

I would agree with the consensus that the drip marks are PVA.

Given your statement above, it sounds like the walls were skimmed first and then the ceiling was done last. Before ceiling skim they applied dilute PVA and this has splashed onto the already plastered walls.
Normally you'd plaster the ceiling first then walls, to avoid drips from above (of either plaster drips or diluted PVA).
If the ceiling was just new board, no idea why they would PVA first. It may have been an overskim of the existing plastered ceiling would make more sense for PVA use.

Emulsion paint does not like sticking to dilute PVA on new plaster, so I wouldn't apply lots to the walls and try to repaint!
It may be possible to sand lightly the areas of drip marks so that the emulsion will then stick. Diluted emulsion for the wash coat is always more likely to show up PVA. A light sanding local to the drip marks and some neat emulsion may sort it.
You can get a similar problem when applying dilute PVA to feather in plaster against an already raw plastered area. You get some PVA left on the overlap - this generally will cover with paint when you put the neat stuff on.

Failing that, possibly one to ask in the Decorating forum.

If it is only this, then I'd pay the guy.

 

[ree]

Good thinking about the mark free ceiling, and the most probably splashed PVA stained walls.