Strange defects in recently painted wall

[jambokaos87]

Hi guys,

I recently had my hallway redecorated in my ground floor flat, at the start of November. All looked great until Wednesday morning I noticed a strange dark streak in the space between the ceiling and the top of the door frame:

https://drive.google.com/open?id=1-T2TZMsDAVPAFUqOzvCrOyJN-8SPPd_h
https://drive.google.com/open?id=1-T0OX7XSzwu04l4bFjtBzFRilEtALQ_D
https://drive.google.com/open?id=1-R8U1zTgc8qmcnL-3ZW5j8a3kjZ0WZGx

The area doesn't feel damp or wet to the touch but the paint is flaking a tiny bit in the middle. I am borrowing a friend's moisture detector to test it with later. Any ideas on what this could be? A leak maybe?

Thanks,

Jamie

 

[sparkwright]

Hard to say.

Any new plastering been done?

Any PVA been splashed around?

Any filling been done here?

Any grease on the wall?

Any old wallpaper paste on the wall?

Was there any peeling paint before?

 

[jambokaos87]

My plumber came round on Saturday to fix another issue in the flat. He cut a small inspection hole near the stain (that he could get an endoscope into) and used a thermal camera to check for a leak and found no evidence of a leak whatsoever. The plasterboard and drywall near the stain were in excellent condition.

My decorator will be coming back to resolve. Thanks for your input.