A.Lee wrote:
I had to visit a house today, as they had a water leak. Or rather,
their downstairs toilet keeps getting wet.

I had a quick look, expecting to find a dripping pipe, but couldnt see
any fault on the visible pipework.
The water is all over the toilet walls/ceiling downstairs, and has
been there for a while, as there is mushroom like growth on the
ceiling. Directly above is the upstairs toilet and sink. There were
maybe 20 droplets in one corner of the room, and the rest of the room
looked like someone had just had a shower in it.
The outside wall is also wet from just below window height.
Unfortunately, upstairs is covered in laminate, so I couldnt take up
the flooring to see if one of the pipes is leaking from between the
floor onto the ceiling below.

I had a poke at the plaster ceiling, but it all seemed quite solid.
At the rear of the downstairs toilet is an unheated small room (3'
sq.), which has a slight dampness at the ceiling, but is otherwise
dry.

My main thought was there must be a dripping pipe under the upstairs
floor.Though the ceiling doesnt look like it has had water running
through it.


My query-
Has anyone come across such a bad damp problem that has been caused by
condensation?
Am I missing something?
Thanks
Alan.

Alan,

As I have obviously not seen the job, I am going to ask some possibly silly
questions to try and get an idea of the situation - they are not in any
particular order and they may help you elaborate on the situation.

How old is the property?

Where are the soil stack runs?

What is the outside wall made of - brick, stone, cavity, solid - or is it a
prefabricated type of construction?

You say the "plaster" ceiling is solid, would that be plasterboard or lath
and plaster - or possibly even the old asbestos cement type of board.

Is the ceiling wet and crumbly on the edges against the outside wall?

You say that the walls are wet on the inside, is that wall facing into the
prevailing wet weather direction and is it wet only in one place or from
ceiling level down to the floor?

Is that particular room well heated or well ventilated with vents through
walls?

The reasons for the questions:

If there was a pipe leak above the ceiling, the plaster ceiling would feel
very soft and probably bulging and if there is a light fitting nearby, water
would possibly run down through that - unless the ceiling is of the asbestos
cement type board.

If the ceiling is crumbly only on the edge, it may indicate damp penetration
through a solid or through a blocked cavity wall.

If it's a cavity wall, and the soil stack is of asbestos cement or cast iron
(even plastic) there could be a leak where it passes through the wall and
dropping into the cavity onto the window lintel and soaking through the
internal skin - ditto if it's solid or stone but then the water would tend
to 'soak' down - possibly following cracks in the compo or black mortar
jointing.

A number of possible suggestions that may be near or very far away, but I
hope they will help.


BRG