where is this coming from?

[Bullett]

Water leak obviously, not sure when it started of if it's ongoing as we only spotted it yesterday its in a room that's not used all the time.


There is a bathroom above it, we had a previous issue when one of the kids splashed huge amounts of water everywhere and it leaked through. I've pulled the panel off the bath and had a look under. It's got a damp/musty smell but I've run taps and shower and drained it and I can't feel any wetness on the joins above floor level.

It could be the silicon sealing the bath is my other thought.

Alternatively looking at the patten could this be coming in from outside? There is no wetness higher up the walls that I can feel.

[megaphone]

Cavity walls? Could be coming down the cavity and hitting the window reveal, there should be a cavity tray and weep vents, but not always. Post some pics from outside.

[sherman]

My first guess would be the silicone round the bath.

I would spray some soapy spray round the pipework underneath whilst you have the panel off.
Run the taps and check for bubbles.
Then fill the bath so it has a bit of weight and drain it repeating the soap just to be sure though.

Slso check your roof and guttering after the recent storms for damage/blockages.

[M11rph]

Having chased leaks before... it can be tricky!

If you've discounted the obvious visible sources the next step is going to be tracing it in the floor/ceiling void.

These budget endoscopes are very handy. A 10mm hole is easy to repair so you've a chance of finding the source without taking sizeable chunks of plasterboard down.

Something like this https://www.amazon.co.uk/dp/B0C7TXY5G8/ref=sspa_dk...

My last one used my phone rather than a dedicated screen, which does involve a sketchy non-name chinese app to work. Having eventually killed it I'll be getting a standalone unit like the one above.

[Lotobear]

megaphone said:

Cavity walls? Could be coming down the cavity and hitting the window reveal, there should be a cavity tray and weep vents, but not always. Post some pics from outside.

This was my first thought too despite the bath above - it's sensible of course to chase the obvious cause first but they can and often do turn out to be a red herring

Is there another window above that one and how is the cill detailing/seal around the first floor window. Is it West/SW facing?

...any 'hole' through a cavity wall (like a window) is always a vulnerable point and worth investigating.

[wombleh]

We’ve had several leaks from sealant failing so I tend to look at that first, worth replacing to see if that sorts it as a tube is fairly cheap.

[TimeforTea]

We have similar with two windows, only happens when significant rain (eg really heavy all day), has this happend after heavy rain.

[Bazil Bush]

TimeforTea said:

We have similar with two windows, only happens when significant rain (eg really heavy all day), has this happend after heavy rain.

Likewise, we have a similar issue when we get driving rain against one of our windows.

Believe ours is due to there being no lintel on outside brickwork as originally the houses relied on wooden windows to support upper bricks above window but they’ve been changed over time to UPVC.

When you walk around our estate there’s numerous houses that have had lintel’s retro fitted as you can tell by the difference in the bricks to the original.

Not necessarily your issue OP but worth bearing in mind.

Ours is fine when the rain comes “straight down “ but heavy and driving against the window gives us the issue.

[Bullett]

Thanks for the input, I think we've disregarded the window question for now.

Did find a damp patch behind the bath looked still wet, so the prevailing theory is that this is the shower in the wall that's leaking. Still open to other possibilities but this is the strongest one right now. Only way to tell is to get behind the tiles so I think we will call the insurance.

We've stopped the kids using that bathroom for now so hopefully it will dry out a bit.