Leaking extension roof (Ed.)

[adamm1]

Single story extension is leaking in heavy rain - we have a flat ceiling inside and in heavy rain both spotlights are dripping heavily with water. One towards the back of the extension wall and one towards the front. We’ve also got 2 other wet patches. We’ve been on the roof and inspected the tiles, removed tiles and everything looks fine. No holes in the felt etc.
there’s cavity trays installed, but I’m really puzzled at how so much water can be coming from the trays? The extension is on a gable end of a house. With No windows above.

Could there be an issue with the motar around the bricks that have gone back in? And they are leaving water seap thru?

Iv atttached photos - the lead had been slightly lifted by us, otherwise it’s always flat on the wall.

 

[Notch7]

Is your extension ceiling flush with the original house ceiling - ie can you see the boxed in steel or is it all flush?

usually water getting in to the cavity and running down would hit the top of the steel then run around until it found a path to get in or cause a damp patch.


I can’t see any weep holes for the cavity trays although I guess the altered pointing indicates something was done.

Its certainly a large amount of brickwork above so proper cavity trays are a must.


As for the roof, does the roof pitch comply with the minimum fall for the roof tile manufacturers spec - I’m not a roofer so have no idea on this, just trying to think of possibles.

 

[adamm1]

I mate. There is no steel, inside there’s only a small door leading into the extension. It’s a very small room.

There are weep holes but no weep vents? Just gaps in the brick work. I’m very puzzled because the water is a lot. Constant dripping in heavy rain. Im confused as to how so much could be coming thru the cavity trays and into the building?
As for the roof it’s fine, the tiles go down to 12.5 and the pitch is around 18-19.

 

[adamm1]

@Notch7

 

[Notch7]

There is no steel, inside there’s only a small door leading into the extension. It’s a very small room

In that case any water getting into the cavity would just run down to the ground, it shouldn’t be coming out in the ceiling

Constant dripping in heavy rain. Im confused as to how so much could be coming thru the cavity trays and into the building?

I agree, that shouldn’t be connected.

 

[Notch7]

Are the verges correct?

hopefully a pro roofer will be along to provide some more insight shortly

 

[adamm1]

@notch but if there’s water coming into the cavity shouldn’t it hit the cavity trays? But again, if water was hitting the cavity trays how is is tracking under them and into the building? When we lifted the lead we could see some bricks along the back wall were wet too.
Someone advised me to take the cavity trays out completely and just put a normal lead flashing into the brick work and keep the cavity clear.

But again. I’m still confused by the amount of water, when we lifted around tiles all the felt and battern looks dry. It’s so confusing

 

[adamm1]

@Notch7 I thought this - but there’s a dry verge system installed and it’s been felted very well. But again, the verge goes up into the existing kitchen in the next room, So how could water be tracking over 3 rafters and into the extension? Really strange

 

[adamm1]

@Notch7

 

[Notch7]

@notch but if there’s water coming into the cavity shouldn’t it hit the cavity trays? But again, if water was hitting the cavity trays how is is tracking under them and into the building? When we lifted the lead we could see some bricks along the back wall were wet too

We’re there cavity trays fitted or did they put in lead or DPM?

the brickwork should not be wet below the lead flashing - cavity trays correctly installed should discharge water out through weep holes and bricks should be dry below the flashing.

they are horrible things to fit mind you.

but even if water got under the trays, it’s hard to see it coming in to the ceiling away from the wall

 

[Notch7]

Are you confident the valley is not leaking.

the lead work at the top of the valley and to the right seems a bit untidy

 

[adamm1]

@Notch7 The cavity tray are the type with lead attached to them, so the cavity tray is installed into the brick work and the lead hangs down.
Yes I know they are a pain and all builders hate them. But they look like they’ve all been overlapped. The cavity of the house is only 70mm, so they were a right pig to try and get in .. yes the lead on The Valley side doesn’t look great - we will probably add more lead there but my thinking is - of The Valley was leaking, how is the water making its away across the rafters and into the extension area? There’s no noggins in the rafters (as this could be a way for the water to track across) but there’s not.

 

[Notch7]

@Notch7 The cavity tray are the type with lead attached to them, so the cavity tray is installed into the brick work and the lead hangs down.
Yes I know they are a pain and all builders hate them. But they look like they’ve all been overlapped. The cavity of the house is only 70mm, so they were a right pig to try and get in .. yes the lead on The Valley side doesn’t look great - we will probably add more lead there but my thinking is - of The Valley was leaking, how is the water making its away across the rafters and into the extension area? There’s no noggins in the rafters (as this could be a way for the water to track across) but there’s not.

Yeah I dont have any obvious answers just trying to look at the possibles

leaks are the worst thing to find - especially on a plastered ceiling as they could track anywhere so the leak source is difficult to ascertain from inside.

I suppose above the plasterboard is insulated so putting a camera through a downlighter hole won’t tell you anything

 

[adamm1]

@Notch7 yeah I totally agree. It’s really puzzling.
When we lifted the lead (roughly were the down lights are) the brick work was damp. Which was telling me water was getting in somewhere there. But we’ve had 2 damp patches about 2 foot to the right side of the light too.
It’s frustrating as I really want to get to the bottom of it.

One thing - do you think rain could be blowing thru the motar around the brick work where the vanity trays are? It doesn’t look the best if I’m honest. And if so, could this cause a lot of water to come into the building? I’m guessing not?

 

[adamm1]

@Notch7 as you can see, look how much water is in the tray. It’s a lot. And that’s a screenshot from a video