Our house is a 1946 built ex council property that has had uPVC windows fitted and when we moved in afew years ago we had cavity wall insulation put in.
We suffer from damp, condensation and black mould growth quite badly, so wonder what is causing it?
In particular, in the window reveals where there would be a cavity behind the plasterwork, it is constantly wet this time of year. I thought that rain and damp was getting in from outside so resealed around the windows on the outside. It has made no difference though. The wet extends from top of the window to the internal cill, about 4" wide all the way down in upstairs windows and about 2" wide downstairs.
The black mould only appears on the upstairs ceilings, where the ceiling meets the outside wall. The upstairs ceilings are those odd shaped ones that curve downwards to the wall. Therfore the gap in the attic between tiles and ceiling plasterboard is only a few inches I'd say. I had considered putting insulation boards in the gap, but my neighbour did this and reported no difference. We use mould and mildew spray, but it returns in a couple of weeks.
The other day, we noticed that where we had a some clothes against an outside wall in the bedroom, when the clothes were moved the wall was freezing cold and wet to the touch. The clothes were also very damp.
To me it suggests that the cold air is transferring across the cavity and that the cavity insulation is not working or is in fact making it worse.
I was reading that ventilation is key to stopping mould growth, but even with windows left ajar, it doesn't help. I noticed that the wall vents on the outside skin of the house have been blocked with silicon by the cavity wall installers, is that the correct procedure?
Any help or advice appreciated.
We suffer from damp, condensation and black mould growth quite badly, so wonder what is causing it?
In particular, in the window reveals where there would be a cavity behind the plasterwork, it is constantly wet this time of year. I thought that rain and damp was getting in from outside so resealed around the windows on the outside. It has made no difference though. The wet extends from top of the window to the internal cill, about 4" wide all the way down in upstairs windows and about 2" wide downstairs.
The black mould only appears on the upstairs ceilings, where the ceiling meets the outside wall. The upstairs ceilings are those odd shaped ones that curve downwards to the wall. Therfore the gap in the attic between tiles and ceiling plasterboard is only a few inches I'd say. I had considered putting insulation boards in the gap, but my neighbour did this and reported no difference. We use mould and mildew spray, but it returns in a couple of weeks.
The other day, we noticed that where we had a some clothes against an outside wall in the bedroom, when the clothes were moved the wall was freezing cold and wet to the touch. The clothes were also very damp.
To me it suggests that the cold air is transferring across the cavity and that the cavity insulation is not working or is in fact making it worse.
I was reading that ventilation is key to stopping mould growth, but even with windows left ajar, it doesn't help. I noticed that the wall vents on the outside skin of the house have been blocked with silicon by the cavity wall installers, is that the correct procedure?
Any help or advice appreciated.