Blothes in paint work

[bob2611]

I had a plasterer reskim a room. Now I have started to paint, the paint is becoming blotchy in places. It doesn't seem to be my paint (simple matt emulsion), it seems to be an issue with the plastering.

can anyone advise on the cause and what I can do

Untitled

• bob2611
• 1 Sep 2012
• 1

 

[TheDec]

Bob,

Did you thin your first coat of emulsion down, (mist coat) or did you apply it neat from the container. Not thinning your first coat can often emulate this sought of problem, another factor to consider at this stage could be that certain areas of skim have been over polished thus rejecting any form of bond between paint system and plaster skim.

Dec

 

[bob2611]

I did apply a watered down coat twice. These blotches seem to come through. It's like the blothes are just not absorbing paint. I rang the plasterer. He said, firstly it's bad paint and then said this is a "fact of life" when you have plaster over a cement\sand mix. He says it's salt coming through. I think this is just BS.

Can anyone help me to fix this. I am really in a bind. The plasterer aint coming back to reskim.

I enclose some higher res pics.
http://www.flickr.com/photos/60469794@N05/7908863474/in/photostream
http://www.flickr.com/photos/60469794@N05/7908864144/in/photostream
http://www.flickr.com/photos/60469794@N05/7908862700/in/photostream

 

[bob2611]

found this thread.

http://www.boards.ie/vbulletin/showthread.php?p=53268454

Can anyone confirm sanding back and painting witha brush will help

 

[joe-90]

Sanding is a bad idea on plaster as it gives texture issues.

It looks like PVA bleed to me.

Get some cheap oil undercoat, thin it 10% with white spirit and paint over the blotchy area and allow to dry.

Then repaint as you did before and the problem will be gone.