I have been in my end of terrace approx 1910 house for around a year. If looking at the property from front to back, I have a front sitting room, separate dining room behind that (which would have been the original back room), with a kitchen extension on the back.
The middle room has suffered from damp patches on the wallpaper since I moved in. These were odd, no consistency to them so assume not rising damp. A few were on internal walls, roughly at skirting board level. The larger stains were on the external wall, which also contains the chimney breast. Part of the staining extends from chimney breast and wraps around to external wall. There was never any mould evident and no real damp smell. In the past I suspect damp problems did occur, as the original wooden floor has been totally replaced with cement floor. I would've expected a proper damp proof would've been installed, so don't understand the stains on internal walls. On taking up the carpet, there is no evidence of damp staining, except next to a radiator where there was also some rotten skirting, so assumed a previous rad leak, this isn't ongoing. My dad totally cleared out the cavity, it was blocked in places with rubbish so this may have been the original cause of dampness, as could have been a blocked sewer running along the outside wall. In the middle room, on the wall facing onto the exterior, my dad took off the plaster back to the bricks ... and it was completely dry. He painted a black tar waterproofing layer, re-rendered and skim plastered. But, it appears some of the staining is coming back. Could this be because he didn't take off enough ... I have read something about salts coming back if not treated properly. It could be that condensation is contributing to the problem - in a few weeks am having cavities insulated, will this help? There is also poor air circulation in this middle room. However, I have never seen condensation on the windows.
I have now removed all wallpaper, underneath seems to be some vinyl paint, I am scraping this off where I can to let the walls breathe.
I just don't know what to do next - should we attempt again to treat the affected areas by removing plaster, re-rendering, etc - how much of a margin around the original stain do we need to go? Or could there be another cause to this problem ... dad did the same with an internal wall patch, and this is begining to come back again, though not as dramatic. Should we be thinking that there is a failure in damp proof course, although this seems unlikely when both areas proved to be bone dry underneath the plaster.
Any pointers would be helpful.
Many thanks.
The middle room has suffered from damp patches on the wallpaper since I moved in. These were odd, no consistency to them so assume not rising damp. A few were on internal walls, roughly at skirting board level. The larger stains were on the external wall, which also contains the chimney breast. Part of the staining extends from chimney breast and wraps around to external wall. There was never any mould evident and no real damp smell. In the past I suspect damp problems did occur, as the original wooden floor has been totally replaced with cement floor. I would've expected a proper damp proof would've been installed, so don't understand the stains on internal walls. On taking up the carpet, there is no evidence of damp staining, except next to a radiator where there was also some rotten skirting, so assumed a previous rad leak, this isn't ongoing. My dad totally cleared out the cavity, it was blocked in places with rubbish so this may have been the original cause of dampness, as could have been a blocked sewer running along the outside wall. In the middle room, on the wall facing onto the exterior, my dad took off the plaster back to the bricks ... and it was completely dry. He painted a black tar waterproofing layer, re-rendered and skim plastered. But, it appears some of the staining is coming back. Could this be because he didn't take off enough ... I have read something about salts coming back if not treated properly. It could be that condensation is contributing to the problem - in a few weeks am having cavities insulated, will this help? There is also poor air circulation in this middle room. However, I have never seen condensation on the windows.
I have now removed all wallpaper, underneath seems to be some vinyl paint, I am scraping this off where I can to let the walls breathe.
I just don't know what to do next - should we attempt again to treat the affected areas by removing plaster, re-rendering, etc - how much of a margin around the original stain do we need to go? Or could there be another cause to this problem ... dad did the same with an internal wall patch, and this is begining to come back again, though not as dramatic. Should we be thinking that there is a failure in damp proof course, although this seems unlikely when both areas proved to be bone dry underneath the plaster.
Any pointers would be helpful.
Many thanks.
