Can anyone explain this?

[Kathyan]

Bit of a long one, sorry! We had our bathroom redone at the beginning of March this year. Everything (except the toilet) has been replaced. When the guy came to measure for the vinyl, he suggested that we have the floor boarded so that the gaps in the floorboards wouldn't show through. We had this done and the floor was laid. After a couple of months, the floor began to bubble. We thought this was due to the weather and the boarding expanding. It went on for quite a while and because nothing had come through the kitchen ceiling, we assumed that there were no leaks. Until last Monday, when we noticed a damp patch on the kitchen ceiling. We called the plumber and he took up part of the vinyl and the boarding underneath was soaking wet! He removed the vanity unit and took up all the boarding, put the vanity unit back and checked all the pipes, couldn't find anything and said it must be condensation! The next morning my daughter noticed a wet patch behind the toilet. I had a look and noticed that the bolt holding the cistern onto the toilet pan was wet. I put a bucket underneath and during the day it started filling up, but very slowly. I got the plumber to come and check and he did something and said it would be OK. It wasn't! A friend of my daughters (who is a plumber) had a look at it yesterday and said it was the 'doughnut' between the cistern and pan that was worn. As a temporary measure, he has siliconed it and it seems to have solved the leak. The floor has now dried out completely. Now what we can't understand is, why we didn't notice there was a leak (albeit a slow one) for three months? And would a slow leak from the toilet soak the boards like it did? Any explanations would be gratefully received!

[ummmm]

In my experience...yes it would soak the boards like you explained. We had a slow leak here and not not only did the boards need replacing but also the joists. because the leak was so slow it must have been going on for a long time before affecting the ceilings of the rooms below.

[RATTER15]

A slow leak will take time to show on the ceiling as first it will trickle along the flooring, gradually being absorbed and partially evaporating, when the boards can no longer soak this up due to them being sodden it will eventually drip down through, this could also be absorbed by, things like insulation, debris and the ceiling will actually absorb a fair bit bit before showing signs of damage.

[ummmm]

We had to pull the ceiling down in the room below in the end.

[Kathyan]

Thanks for your replies. That's that cleared up!

[alavahalf]

Another possible cause...You say you had your bathroom re-done in March ... over the winter months I got called to more than one or two of these 'cistern leaks'...
Everyone of them was condensation, which by the forces of nature... always ends up at the lowest point (the screws holding the cistern down, and then the floor).
Every time you flush...... the cistern is filled with cold water. The surface of the cistern is almost room temperature and the cold water is a lot colder..this will result in condensation running down the cistern and usually endind up on the floor.
But of course as soon as the weather warms up, the condensation will cease.
It may just have been a coincidence that the application of silicone coincided with the leak stopping.
A lot of people were under the impression thet their cistern was leaking, but infact it was'nt.
You may well not have noticed the leak as the water was dissapearing under the edge of the vinyl, and getting soaked up by the boards that were laid.
This is what caused the bubbling.
Idealy the boards should have been laid, then the new vinyl laid immediately...
Then the new pan fitted on top of the vinyl ...

[chokkie]

Sounds a similar situation to the one my mother in law had a month or so ago. Unfortunately, all the slow leakage problems caused her (tiny) loo to stink our her small flat. Anyway, she's got it sorted out now.

I would be inclined to find myself a new plumber, though.

[AlBags]

It may not have been the plumbers fault ..
Any movement of the pan or cistern could cause a leak .. especially if the pan and cistern were not fixed properly.

[buildersmate]

Bear in mind that the only time that a few drops of water will come out is when the loo is actually being flushed - not at all other times (though I agree it could be caused by condensation, as alavahalf suggested).