Damp issue -corner of extension

28lbs · Post by **28lbs** » Sun Oct 01, 2023 11:16 am

Hi
I’m after some advice please. We are dealing with damp in the corner of our living room - which is an extension built in the 90s butted against the main house (built in 1980). Brick, cavity insulation etc with half render. We have stripped the paint back so we can monitor.

We have cleaned all gutters, fixed the cracks in the render and filled a couple of holes where the cement has weathered but still we get a damp patch that grows after rain and then shrinks again when sunny/dry. Any ideas please??

Inside and outside photos posted for reference.
You can see a wet patch under the render which is roughly the same height as the corner of the living room.

Thanks in advance

dewaltdisney · Post by **dewaltdisney** » Sun Oct 01, 2023 11:53 am

It is definately water ingress from somewhere and normally it would suggest a gutter or roof issue but you have checked that. The only other issue is are you sure there is not a gripping water pipe inside?

DWD

28lbs · Post by **28lbs** » Sun Oct 01, 2023 1:05 pm

Thanks for your swift reply. The main bedroom is above and the only water pipe would be from the landing to the radiator. I can check under the floorboards but I’m pretty certain it’s a weather dependent damp issue. Definitely worse after it rains!

Another photo on the external wall incase it gives any clues! Area circled in red is the level of the ceiling in living room where issue is :) Sorry all photos are sideways!

dewaltdisney · Post by **dewaltdisney** » Sun Oct 01, 2023 4:04 pm

It looks like it might be a roof issue perhaps. The water stains might suggest that water is permeating down the wall under the render and it is reaching a block to its pathway and spreading out. I think I would consider getting a roofer to check the valley on the gable to roof join. If it is lead it can crack over time and a small fissure can allow a lot of water in when it is raining hard. Just a logical suggestion.

DWD