Leaking lavvy... but from where?

[Lobster]

The floor around my bathroom loo is frequently slightly damp. The floor is currently finished(?) in natural WBP plywood, but now my longterm (cough) bathroom renovation is pretty well complete, I can't put this off much longer, especially as SWMBO is dropping hints that a rather more permanent and attractive flooring solution might be in order...

Anyway, this damp patch comes and goes; sometimes at the front of the toilet, sometimes at the sides or rear, sometimes all round. Potential causes I can come up with:

1. Two boy-children with poor aim (but they swear they aren't guilty and I think I believe them)

1. Condensation from close-coupled cistern (but it happens year round, even now)

2. Leak from soil pipe seal or water supply

1. Leak from cistern somewhere (has integral overflow)

2. Crack in bowl (but it was new 2 years ago and I certainly can't see any blemishes from above, although I haven't looked underneath).

I've regularly checked all round the outside of the bowl, soil pipe and cistern looking for wet areas which might point me in the right direction, but it's always bone dry.

Are there any other potential cause I've missed? Anyone got any bright ideas as to how to nail down the cause? Wondered about force-feeding beetroot to the kids to rule out (1), but SWMBO's unenthusiastic.

Admittedly I've put off dismantling the whole loo to check underneath, but I genuinely don't believe that's it...

Thanks David

[Mogga]

My initial thought was you have young boys in the house.

Ahh.

Do you see condensation on the loo?

Wouldn't this be constant?

[The Medway Handyman]

Get a bright LED torch. Great for spotting water leaks, sligtest drop seems to glow in the light.

[Franko]

Our toilet at work did exactly the same - always spotted the leak intermittently around the base of the toilet but couldn't work out where it was coming from for ages. Eventually we realised that it was always after a rather portly colleague had paid a 'sit down' visit and as the pan wasn't screwed down that well it wobbled under his weight and the flush pipe leaked as he flushed, after he left the lavvy, the pipe reseated itself .... sorry ..... just read 'close coupled cistern' ..... forget my idea :)

[Cicero]

================================== Check the area around the rubber doughnut between cistern and pan. If there is any leak here it's most likely to show up during or immediately after flushing. Check the position of the two screws holding the cistern to the wall to make sure they're not preventing the cistern sitting properly on the pan.

Cic.

[The Natural Philosopher]

I've had leaks like this..

One turned out to be a slightly offset soil pipe that dribbled a bit every time it was flushed - fulled the rubber thing with silicone and stopped it.

The other was the cistern-to-loo thing. More silicone helped.

Tying bits of loo paper all round it helped ID where the leaks were coming from

Another leak turned out to be simply the wife splashing water out of the adjacent basin..

[Matty F]

That was the reason I got water on the floor. Here's how I fixed it once and for all:

[Part timer]

We had an intermittant leak down one side of our cistern (hairline crack between water inlet pipe hole and the base), cured for now with Screwfix silicone sealant after draining and drying it out.

[Heliotrope Smith]

[mcbrien410]

A small pool of water developed in the back of my porcelain toilet just above the soil exit connection. I dried it out and thought no more of it. About a week later it was back, repeat procedure but back it came. No visible cracks anywhere. I mixed about a third of a pint of water with PVA glue to make a thin milky solution. I poured this into the water in the toilet and left it overnight. That was the end of the pool of water appearing. That was 1981 and it is still just fine.

Regards Chris.