Leaking Roof Terrace at French Doors

Hi,

I live in a flat in an old 1830's house where part of my ceiling is the outside terrace for the flat above. A year or so I noticed a damp patch on the ceiling below the terrace which eventually started dripping in our room below and I drilled a small hole to relieve the pressure. We had a surveyor in who diagnosed the problem as probably needing a new roof laid but that we should first try sealing and repairing the french doors opening onto the terrace in case water was leaking in that way. One year on we have tried both things and guess what it still leaks! The new asphalt roof and terrace looks like a really tidy job which was quickly and reasonably done and I am sure that is watertight; so I am left with trying to work out how water could be getting in. The one candidate I can see is the afore mentioned French Doors/Windows but I don't really know where to start and as you would imagine everyone seems to have their own (costly) solution.

The only real information I have to go on is that the water comes through where the terrace meets the house and smack in the middle of where the french doors open. Of course water can travel a long way but this looks suspicious. I have also heard that there should be a lead lip which sits under the doors and chanels any water which leaks down through the door out onto the roof. Is this true? If so, I can see that there is lead there but I can't tell whether it extends under the door.

Any advise would be really appreciated. Even if it is just which would be the best type of person to get. I got in a roof person and I got a new roof!

Pete

there should be a lead apron running beneath the cill of your french doors which continues under the doors and turns up to the inside of your cill creating a tray.
if this is not present or has failed the only solution would be to remove the doors and create a proper lead detail.
its no use messing about with silicone sealant as this would be a short term fix.

Thanks Alistair, any way of checking without taking the door out? How about pressure hosing that piece of the door and seeing if it leaks downstairs?

i wouldnt use a pressure hose pete!
just a normal hose should suffice.

good luck.