Damp issue in the party wall

We need to know where the damp Is first on the party wall otherwise I cant say with certainty is the damp at ground level so bottom of the wall, or is it ceiling level so top of the wall? These are good indicators of what’s going on high level damp usually caused by either leaking roof/chimney for various reasons sometimes rare though shot pointing on brick walls of house can cause damp all over the wall. If damp course at ground level isn’t there or is doing it job anymore this would be low level damp on the wall it could Also be ground level has been built up higher then damp level accidentally this is also quite common thing you see . There a lot of factors to consider here and going off the information you given it near impossible to say with certainty. A good roofer or general builder will be able to identify what causing the damp I’d start a job lead on mybuilder.com. where would you post this lead as I see a lot of people posting leads in the wrong sections. Well I’d start with getting a roofer round so post in roofing section if you think the chimney is something to do with the damp failing that a general builder so general building section failing that a plumber so plumbing section as you might have leaking pipe work inside the walls failing that a specialist damp proofer on the damp proofing section to get the issue sorted otherwise were just throwing second guesses out there and could be completely wrong and sending you in the wrong direction. As you can see damp is quite a complex issue with lots of factors to consider. PS I don’t think your neighbours chimney will cause you damp that is why there is a diving wall to prevent this but again can’t say with certainty without seeing everything first. Sometimes too you just gotta open your windows to allow the air to flow I’ve been to a few damp issues were this was the main cause of the issue if your house is stuffy open the windows a jar every now and then especially after having a hot shower or bath and cooking. Hope this help and sends you in the right direction. Regards Frankie BT Roofing Services

the fact the chimney stack is still on the roof is most likely the cause of one area of dampness ,cement work, lead flashing, eroded brickwork ect ect, without looking its not really possible to say what is causing the dampness on the other wall, you best bet is post the job on the site and get a local expert round to asses the cause/cost to remedy. good luck alex

Hi,if I’m understanding you right next doors stack could be leaking and you could be showing signs of this now in your property also if you have had a leak I advise putting a dehumidifier in the room to try and dry out the patches,this may also help answer your questions as if the moisture starts to reappear this may give you some indication on where the water is coming from,id love to help more but there is only so much to say without looking at the job at hand

if the stack is showing 4 pots, 2 would be yours. If the chimney breasts have been removed on your side , water may be entering through the remaining stack and transferring to your side of the party wall. It is also possible that the flue has been constructed within the party wall. thus giving a direct route for any water ingress from top to bottom. Check the stack in the loft below the chimney. If the brickwork corbels out into the loft area, the flue likely still remains. Easy way to check, drill a hole into wall, if the flue is within the party wall, the wall will only be 2 inches in width and the drill will pop into a void (flue)