Problem damp wall!!

plett4128

Can anyone out there please help advise me on my damp problem as I am at a complete loss.

The wall in question is an upstairs outer bedroom wall of a 1800/1900s middle terraced house, that has been repointed outside, primed and painted with waterproof masonary paint and then replastered and repainted inside. The problem I have is that around sill level in the middle of the wall I have a wet patch that appears whenever it rains and at the top left hand side of the wall where the ceiling is this is also wet. We have had the gutterings checked and this does not appear to be the problem but if the walls are not wiped dry when they become wet then this then turns into black mould.

I really dont know what to do as I just keep spending money on it and nothings seems to fix it.

Any advice would be greatly recieved.

iamcornholio

For the damp near the window

Water tends to get in under the cill, due to no drip, or inadequate drip on the cill, or a gap between cill and wall
Or its getting in via the frame or its connection with the cill - especially if the cill is brick, stone or tile and different to the frame

Near the ceiling

If you are certain that gutters and the wall outside are OK, then the next likely place is that rain is getting in at the eaves, and missing the gutter and running behind any fascia and into the wall behind the gutter

You need to confirm that any felt under the tiles has not rotted where it normally projects into the gutter, or that there are no other obvious probelms with the tiles at the eaves

Oldbanger666

Double check the gutters for sure... and as above ^^^^ check the slates/tiles to see if they're broken or cracked

plett4128

Thanks for your replies so far.......

There doesent seem to be any problem with the tiles/slates and it was only last summer that we had a complete new roof fitted inc felt/membrane.

Also the window sill is made of wood and apparently our house does not have wall cavities. These I was told my a recent workman who tanked out my living room.

Any further suggestions??

Gazing_On_Sunsets

Is it definitely only happening when it rains? One thing you could try is on a dry day, get a hose and run it at the places you suspect rain is getting in, and see what happens. I know it's counter intuitive but at least you can see if it is the rain, and where the weakness is.

The reason I ask if it is rain is just that if you've got an old house with no cavity walls, and you've waterproofed the outside with paint and the inside with modern plaster, your house can't breathe. Older houses were designed for lime plaster which is breathable. Add on double glazing, central heating and insulation, and maybe a modern tendency to not open windows, and you could be creating condensation and damp problems.