Patches on walls

[jake83]

I've recently had my walls plasterboarded and plastered and now I'm getting damp patches. Can anyone tell me why? See attached pic

 

[brimplas1]

Looks like it's been dot and dabbed in an older proprty...... old property's without a proper cavity/ damp course membrane / insulation should be floated ...

 

[jake83]

What can I do to stop it or cover this up? It's on other walls too

 

[Danny]

is it on only the plasterboarded walls? @jake83