Hello,

At the back of my victorian terrace is a small bedroom that has, I am
told by a neighbour, a 100cm wide by 20cm deep chimney breast. They
had theirs removed when they converted the corresponding room in their
house to a bathroom. When it rains heavily “damp” patches appear at
the top of the wall and on the part of the ceiling nearest the chimney
breast. The patches on the wall are darker than the surrounding
emulsioned paper and the patches on the ceiling are yellow in tint. No
paper on the wall has lifted. After a good few dry days the patches
“recede”. A roofer has been up there and had a good look. He says the
tiles are intact and there is no sign of damp or wet under the tiles.
The roof is at a fairly shallow pitch (I believe this part of the
house is an extension built in the 30s) at the back. The roofer
suggests an external wall vent needs to be installed.

Has anyone else come across a similar problem and fixed it? I have no
problem about getting such a vent installed – but not if it doesn't
solve the problem.

Thanks

Clive

Clive wrote:
Hello,

At the back of my victorian terrace is a small bedroom that has, I am
told by a neighbour, a 100cm wide by 20cm deep chimney breast. They
had theirs removed when they converted the corresponding room in their
house to a bathroom. When it rains heavily “damp” patches appear at
the top of the wall and on the part of the ceiling nearest the chimney
breast. The patches on the wall are darker than the surrounding
emulsioned paper and the patches on the ceiling are yellow in tint. No
paper on the wall has lifted. After a good few dry days the patches
“recede”. A roofer has been up there and had a good look. He says the
tiles are intact and there is no sign of damp or wet under the tiles.
The roof is at a fairly shallow pitch (I believe this part of the
house is an extension built in the 30s) at the back. The roofer
suggests an external wall vent needs to be installed.

Has anyone else come across a similar problem and fixed it? I have no
problem about getting such a vent installed – but not if it doesn't
solve the problem.

Thanks

Clive
It is difficult to believe that this is not being caused by some water
penetration give the correlation with rain.
An external vent may well help reduce the problem as will good internal
ventilation but i don't think it will be a 100% fix.
Maybe a good look round in the loft and placement of a few telltales of
kitchen paper to see where the water might be coming in.

Bob

In article ,
Clive writes:
Hello,

At the back of my victorian terrace is a small bedroom that has, I am
told by a neighbour, a 100cm wide by 20cm deep chimney breast. They
had theirs removed when they converted the corresponding room in their
house to a bathroom. When it rains heavily =93damp=94 patches appear at
the top of the wall and on the part of the ceiling nearest the chimney
breast. The patches on the wall are darker than the surrounding
emulsioned paper and the patches on the ceiling are yellow in tint. No
paper on the wall has lifted. After a good few dry days the patches
=93recede=94. A roofer has been up there and had a good look. He says the
tiles are intact and there is no sign of damp or wet under the tiles.
The roof is at a fairly shallow pitch (I believe this part of the
house is an extension built in the 30s) at the back. The roofer
suggests an external wall vent needs to be installed.

Has anyone else come across a similar problem and fixed it? I have no
problem about getting such a vent installed =96 but not if it doesn't
solve the problem.

The symptoms you describe (damp visible when it's been raining)
are consistent with a rainwater leak somewhere. Have you been
into the loft above to look for water penetration under the roof?
Failed flashing up the chimney breast would seem likely in this
case.

The solution he is proposing is a workaround for condensation,
but that's not obviously the cause of your damp, based on
what you've said.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]