Leaking Ground Floor Bay Window Ceiling

[bobsy12]

I've been cleaning the inside of my downstairs bay window yesterday and found that rain water has managed to come through the bay ceiling and onto the window sill during the recent heavy rains. This has never happened before. Not a lot of water has come through. I've been up on the ladder checking out the plastic bay roof and the lead flashing looking for signs of holes or flashing creases but nothing has jumped out. I cant work out where the water has come through.

I've never had to do any roof work before, so this is all new to me and so I've no idea what I'm looking for. I've attached some photos of the roof, lead flashing and 1 photo of what appears to be hairline cracks of the plastic roof (although not sure if the cracks are all the way through).

Any recommendations much appreciated.

 

[oldbutnotdead]

Is there any guttering? Is there a proper drip edge on the flat face of the roof (where the gutter ought to be). Is the water definitely coming through the ceiling? (Not just condensation or silicon fail on the presumed uPVC windows)?

 

[bobsy12]

Guttering works all fine and there is a proper drip edge. I've checked the windows and they are all ok. I don't think we have condensation problems. I'm a bit stumped.

 

[oldbutnotdead]

Aah, just had a better look at your hairline cracks. That is a GRP roof isn't it?
If it is GRP then its possible the topcoat was on a bit thick, either that or the deck has moved slightly- whichever, that will eventually cause damage.
Assuming it is GRP repair is to grind the topcoat off til you can see the fibreglass mat. If the cracks go through the mat as well then grind enough topcoat off so you can relaminate with a good 50mm clearance to the cracks. There are plenty of Youtube videos, problem is its a small area & it'll be tricky colour-matching the topcoat

 

[bobsy12]

I think its GRP. I'll take a look at doing a grp repair. many thanks.