Since April damp patches have appeared on the internal wall of the hallway of my Victorian terrace. They appear to be equally spread out and are not affected by rain water. My neighbour does not seem to have any issues with damp. I have read a lot about rising damp not being a reason for this but am at a loss as to how to resolve it. Any ideas would be greatly appreciated - I will be contacting a damp specialist but it would be helpful if I could at least have some idea!