DIY Doctor UK DIY Forums

Hello,

I have some damp issues with my flat and I wonder if you can give me some advice.

1) Flat above leaked into my bathroom and the wall is very wet, wallpaper is coming off and mould is growing. Some part is so wet, the plaster has turned liquid. The flat above has stopped the leak but what do I need to do to fix the walls? Is drying the wall and replastering enough?

2) A corner of the bedroom is showing some black mould rising from the floor to the ceiling. The flat is on 2nd floor so surely, this can't be rising damp? I have cleaned the wall before and painted with damp seal before wallpapering over. But this has now come back. What can be the root of this?

Many thanks in advance for any advice you can give me!

The best way to deal with this is, to let it dry out over the summer.
Damp dries at about 1mm per 24 hours.
Buy a damp meter and check from time to time.
Keeping the room at a higher temperature than outside is the way to go.
Does this bedroom corner but on to the bathroom wall?
If it does the same applies.
If not, have you had damp there in previous winters?
Does it go away in the summer.
Damp in bedrooms is usually down to lack of ventilation in winter aided by keeping the windows closed and turning down or off the central heating.
Keeping the room at the same temperature will solve this problem.
Keeping the kitchen and bathroom doors closed and using extractor fans in the kitchen and bathroom when and after cooking and washing helps.

Perry525 wrote:The best way to deal with this is, to let it dry out over the summer.
Damp dries at about 1mm per 24 hours.
Buy a damp meter and check from time to time.
Keeping the room at a higher temperature than outside is the way to go.
Does this bedroom corner but on to the bathroom wall?
If it does the same applies.
If not, have you had damp there in previous winters?
Does it go away in the summer.
Damp in bedrooms is usually down to lack of ventilation in winter aided by keeping the windows closed and turning down or off the central heating.
Keeping the room at the same temperature will solve this problem.
Keeping the kitchen and bathroom doors closed and using extractor fans in the kitchen and bathroom when and after cooking and washing helps.

Thanks Perry525 for your advice. I am letting out the flat so it will be difficult to control. The bedroom is not next to the bathroom. I am guessing that it is caused by general condensation.

I am thinking to install a vent to keep the room aired and fix the corner by 1) clean the mould with a mould cleaner 2) pait it with some damp preventing paint and 3) wallpaper over. Will this be enough? Anything else that can be recommended?

Probably the easiest and quickest fix is to make sure you've got enough ventilation. This can be difficult to do in winter months or if you're in a part of the UK which sees a lot of rainfall. Have you looked into moisture absorbers? Some of them, despite being inexpensive, are quite good and can at least help when the weather is too cold to keep windows open.