Wet patch in plaster?

[TonyD75]

Hi everyone,

I had a small section of a wall plastered back in March, after a gas pipe was recessed into it. Problem is, there's a dark wet-looking patch in the plaster that hasn't dried in all this time. There's no water pipe behind it so could it be a defect with the plaster? It hasn'ty got any bigger but isn't going away. It doesn't feel wet, more cold to the touch.

Any ideas?

Many thanks.

 

[Micilin]

-
-Condensation when warm air hits cold gas pipe?
- Ingress of water around pipe form outside (is it sealed?)

 

[NickB_99]

There's no water pipe behind it so could it be a defect with the plaster? It hasn'ty got any bigger but isn't going away. It doesn't feel wet, more cold to the touch.

Any ideas?

Many thanks.

I don't think it's likely to be a defect in the plaster.
If plaster is out of date etc then the stuff just goes hard way too fast.
I don't think the plaster is your problem.

If it feels cold, then that may be a clue.
Damp patches can appear in plaster if there is condensation due to moisture in the room condensing on the cold surface.
The other stock-reply here is post us a pic, and it may help diagnosis.

You can probably find previous posts regarding condensation by taping up some polythene over the patch to see which side the moisture forms on.
This may help you.

 

[NickB_99]

Sorry Micilin - was typing and missed your post

 

[TonyD75]

Thanks everyone. It's not an external pipe as such, it comes from the gas supply in the understairs cupboard and goes up in the internal wall, through the ceiling/upstairs floor and the airing cupboard and into the loft, where we've had the new boiler installed.

 

[roy c]

There may have been a bit of grease or something on the pipe and its showing thru the plaster...

 

[roughcaster]

It could even be salts/efflorescence showing through as a dark, damp looking patch. Any chance of a photo?

 

[joe-90]

Get a cheapo damp meter.