Bay Window Leak below bay poll but not sure where from

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Hi there, the upstairs bay window in my 1930's house showed signed of water ingress below the internal sill where the front of the bay and side meet at the 130(ish) degree angle. I poured some water in the internal box of the side window where it has drain holes and noticed water starting to drip then I noticed they had drilled through to the sill when fitting and also the external sill was not sealed correctly at the junction with the brickwork. Fixed these two issues and JackPot :D no more drips.

A few days later there was heavy driving rain and water started to come though again :cry: I've taken the internal sill off and can see the lead flashing the window is sitting on and in the corner water is dripping from it. I took a close look with a torch and spotted that water was sitting in the front (closest to outside) of the bay poll that I can see sitting on the flashing o_O

The external seals look fine from what I can see, the sill where the two window angles meet appear to be fully sealed on the outside.

Any idea how water could be making it to the base of the bay poll ?

Thanks in advance
 
A lot of 30’s built properties were thrown up in a hurry , you can get penetration thru the single skin brickwork, is it rendered externally?
 
This window is on the wooden bay frame on the 1st floor. The frame carries clay stiles that I had replaced couple of years ago along with getting a DPM fitted behind them and some insulation.

The leak appears to be coming from the bottom of the bay pole and it only happens when it is both raining and windy so I'd guess water is being driven back up the top of the external sill and getting in that way. The seal around the plastic cladding around the bay pole on the outside looks ok so I'd guess the water is driven up the sill and around the back of the external seal and maybe there is another seal behind that around the pole itself ?
 
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This is going to be impossible to diagnose, are the windows still under a guarantee?

I moved in to the house around 3yrs ago and the previous owner had them fitted about 11yrs prior to that. The company have since gone bust :(
 
I moved in to the house around 3yrs ago and the previous owner had them fitted about 11yrs prior to that. The company have since gone bust :(

Arghhh well over 10 years old then, my thinking was use the IBG and get a specialist to look at it, tracing leaks can be very time consuming - it was when I was doing it, all I can suggest is water doesn't run up hill and don't get fixated at looking at only one ingress point just because the egress is close by
 
Arghhh well over 10 years old then, my thinking was use the IBG and get a specialist to look at it, tracing leaks can be very time consuming - it was when I was doing it, all I can suggest is water doesn't run up hill and don't get fixated at looking at only one ingress point just because the egress is close by

Yeah I think when the weather improves a little I'm going to go up the ladder and remove all the sealant from around the base of where the poll goes down and replace it as best as I can and see if that has any impact.
 
swebb99. What was the outcome of your bay window leak? I have the same issue however timbers completely rotted on a load bearing wall (n). Unfortunately i have just had the house rendered so replacing the frame will be causing some extra pain. Would be good to know if you managed to solve your problem. Thanks
 
Hi basically who has ever installed the original pvc frame had drilled in the wrong places and water which should have been going elsewhere was going in to the holes. In the end I just replaced all my windows because I had to fix other issues to and decided getting some new ones rather than patch 10yr old ones was the way to go. The new one are a lot quieter and also warmer.
 
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