Damp corners no mould in 1851 solid wall property

Johnny_Panic

Hi all -

Long term problem in our box room. 3 of the walls are external. Getting dampness in corner of room pretty much the shape of the torn off wallpaper. Took paper off to investigate and try and remove plaster but it's rock solid so no live plaster. No mould either, usually associated with condensation, but condensation seems to be all I can deduce. Walls are solid, no cavities. Outside walls newly rendered in attempt to address issue a couple of years ago but no luck. Roofer checked roof but no issues. Thought it may be just when it rains but has also reared its head again on other wall adjacent to ripped section during recent cold spell but weather was dry. It's a problem that comes and goes but comes only during cold months. Have thought about perhaps an air brick to help air circulation as sash windows aren't great for it. Sorry for grammar - I'm on my iPhone

Been going on for years now and again, never any mould. Please please somebody help as I keep throwing money at the problem and nothing has worked. Thank you all!

JP

P.s site won't let me post images annoyingly so please email me at dimebag101(at)hotmail(dot)co(dot)uk

Giraff

Hi. Is it a ground floor or upstairs room?

Johnny_Panic

Hiya - it's upstairs. Box room. I have photos of it would help

littlerock

Gap in external pointing somewhere?

Johnny_Panic

All external walls have new render 2 years ago. No exposed brickwork or flaws prior to rendering

dampdaveski

Sounds like a condensation problem Johnny.
Do the walls feel exceptionally cold when they get wet?
If so it will be condensation collecting on the plaster, a good example is when you take a bottle of milk out of the fridge it instantly gets wet. this is the humidity in the air condensating onto the cold surface.
With glass it's instant and you see it, with old plaster it's not instant and over time a damp patch appears....

Remembering that I haven't seen this so forum diagnosis is no match for a site visit by a professional.......
Try a product called Suretherm, its a thermal insulating paint and i've used it many times since it came out last year with exceptionally good results
I won't put a link on just google it.
Good luck
DD

Johnny_Panic

Thank you - I will give it a try. As said previously I can always show pics if need be if you need further material to go by. Will post on this thread when I have some results to share.