Damp patch on bedroom wall

littlemoney

I have an increasing damp patch on an external bedroom wall near an old chimney. It started with the wallpaper and polystyrene sheet coming off the wall which though was the paste failing as I have similar bits peeling elsewhere. Then the plaster started to crumble and show damp.

Years ago there was an open fire in that bedroom but not used in many years. I don't know what was placed inside the chimney and if it was capped though can't see anything from looking outside.

Any ideas please.

 I don't know if it's caused by a roof/gutter problem or a chimney problem. What trade do need to investigate to determine cause of the damp and remedy it. Thanks

barnstar2077

Funnily enough I have the exact same problem.  I plan on getting a roofer in to give my chimney an inspection in January (not a euphemism :  )

Had a mark appear on the wall a few months ago, but because it is a spare room that hasn't been decorated in years and is used for painting stuff etc I didn't twig right away.

The chances are the flashing has developed a fault around the chimney, a loose tile, or the chimney needs repointing.  It is possible it is just due to excess rain, but as you have no knowledge of any maintenance being carried out on the chimney I would say that isn't as likely.

Also, if it used to have a fireplace, is there still ventilation?  Is there ventilation downstairs in a fireplace that is connected to the one above.  I filled in the one downstairs with a simple door and frame, but left a grill to allow for any moisture trapped in the chimney to dry.   

twopenny

Off the wall idea......do you know anyone with a drone that would fly it around there to see if there's anything obvious?

It would be a good way to have a look in the gutters too.

Ventilation in the chimney is a good shout as Barnstar says.

Polystyrene isn't breathable so any damp has probably had time to get to the plaster as it can't go anywhere else so I wouldn't worry too much on that other than needs removing, drying. Might be a good time to get to that while you work on the cause. It can be drying out when the heating is on.

Just hang a picture or mirror over the hole so it's not staring at you

Been a lot of dull and damp weather all this year so it's problem that's come to the fore now.

barnstar2077

Checking the gutters as well as the roof is a good point that I should have mentioned myself!

Also, as the wall is already a mess, removing any remaining polystyrene to let it breath while you find out what is going on might be an idea.

My brother in law had a drone that I asked to borrow too, but he said he lost it on a mountain in Scotland a couple of years back, which is kinda inconvenient for me tbh, but some people are just selfish like that :  ) 

littlemoney

Thanks for your comments

There is a grill fitted for ventilation. I made contact with a roofer who made a quick inspection and said needed to come back and get ladder up. He did say he didn't think it was damp in chimney as the damp patch would be a different colour. Is that true.

 He canceled the visit due to local storm damage. I misheard the date of next visit and am now waiting for reply to my voice mail message.