question about cavity trays

tony3619

Hello, 
I have recently had a very bad leak during the february storms onto a bed room ceiling which has a flat roof balcony directly above. The wall above the ceiling is a cavity wall supported by 2 metal i-joist and my 2 theories are either....
1) Leak under the balcony door onto the ceiling below
2) water penetration through brick into the cavity and no cavity trays to redirect water. 
i have attached a photo in the hopes that someone can tell me if at the level where the wall meets the flat roof flashing i should see weep holes to indicate cavity trays as its an outwall acting as an internal wall. I dont suspect the roof itself has i have poured gallons directly onto it and cannot make the leak happen and it always appears around the same area under this wall/door.
Regards
 

FreeBear

Ref. second image - Is the flashing recessed into the mortar joint, or just stuck to the brickwork ?

It looks like a glue-on type flashing, and if it is just stuck to the wall without being tucked into a chase in the horizontal mortar joint, there is plenty of scope for water to seep down behind. Water has a nasty habit of taking the easy route, and the actual point of penetration could be some distance from where the signs are internally. So examine the flashing carefully, and look for any signs (even small ones) of the flashing coming away from the wall.

The section below the balcony door is protected by the sill, so that is unlikely to be the source of the problem.

tony3619

Thanks for the reply 

The flashing seems to go in-between the brickwork and them covered with mortar. I can see movement when pressing it but I also have another balcony with the same set up which doesnt leak. 
I have to confess that picture of the door is from the other balcony because the other one currently has sealant covering it but the actual cill and frame has much less of an upstand to the decking which allows water to pool. 

So you don't think it could be caused by lack of cavity trays/weep holes? 

Regards 

tony3619

Here are some additional photos of the actual door where I put emergency sealant the day after it happened so don't judge  and a close up of the flashing where it goes into the brick work and no weep holes are present

FreeBear

To my eye, it doesn't look like the flashing is bedded in to the mortar. It looks more like a bit of trim nailed to the wall, and then the flashing stuck to that. The edge is too sharp for it to be folded in anywhere, and there appears to be bumps at regular intervals an inch or two down from the top.

Also wondering if there are any nails/screws in the timber treads that might have punctured the roof covering.

tony3619

The timber treads are on a timber frame which rests on pedestals so no fixture in the roof Itself. I know that cause it took 2 days to get the b****** screws out  plus I've taken the planks up and poured gallons of water on the roof and no sign of leakage.

Are you saying the flashing doesn't look correctly fitted? Or that weep holes are required? It might be worth mentioning that it only occurs in stormy weather with wind and heavy rain. 

FreeBear

tony3619 said: Are you saying the flashing doesn't look correctly fitted? Or that weep holes are required? It might be worth mentioning that it only occurs in stormy weather with wind and heavy rain.

The way the flashing is finished does look suspect. Heavy rain and strong winds will find any weak points and water will get in. Weep holes/vents will do nothing to fix the root cause of the problem - If water is getting in, it will eventually cause corrosion of any catnic type lintels, wall ties, and galvanised corner beads on internal plaster.

Perhaps worth calling in an experienced flat roofer to take a look and give a second opinion.

tony3619

Thanks for the reply 
My original theory was that strong wind was  blowing heavy rain across the wall and under the door  at the corners and down the gap and it was falling directly through the 2 metal ijoist onto the ceiling.

I guess it could be the flashing at the corners of the door....not the door itself...hmm

 

tony3619

FreeBear said:

tony3619 said: Are you saying the flashing doesn't look correctly fitted? Or that weep holes are required? It might be worth mentioning that it only occurs in stormy weather with wind and heavy rain.

The way the flashing is finished does look suspect. Heavy rain and strong winds will find any weak points and water will get in. Weep holes/vents will do nothing to fix the root cause of the problem - If water is getting in, it will eventually cause corrosion of any catnic type lintels, wall ties, and galvanised corner beads on internal plaster.

Perhaps worth calling in an experienced flat roofer to take a look and give a second opinion.

Thought I'd update this thread for people in the future....I finally managed to recreate the leak by pouring water directly onto the join between the upstand and brickwork so it seems I need to seal this somehow? I'm assuming it needs somekind of lead flashing over the top. At the moment I've got duct tape covering it (it's all I had) I've contacted roofers and I'm waiting for a reply,