Leaks above windows

[brum41]

As an update my guy put extra sealant around the window. However the rain yesterday produced same effect.

We only get rain coming through after prolonged bad weather. It took 20 minutes of consistent driving rain before water drips from internal window. But it continues for up to an hour or more after rain as stopped.

It must be driving rain into the cavity but how if i have just had a lintel installed and a cavity tray with weepholes visible can water get past this barrier?

My builder is coming back again as he is perplexed as i am.

 

[Swwils]

Pictures again inside and out as wide as possible.

 

[wessex101]

Looking at the photos in post #8 it looks like the front and middle window have a bizarre lead flashing hanging down above the window and the rear window has nothing.

If this was an attempt to install cavity trays why have they left the lead hanging out of the wall by 4 inches and why does the rear window have nothing?

If that is the case it would suggest whoever did the work didn't have a clue what they were doing so the cavity trays have probably been installed incorrectly. If the cavity tray is installed correctly it should be a totally impermeable barrier and there is no way water should be able to run down and drip from the window head no matter the condition of the the wall or roof above.

 

[brum41]

Hi Wessex. No these pictures were before the work. He removed the lead flashing on those two and put lintels and cavity trays in all three. The first two (touch wood) have now been fine. It is the one furthest away which is the problem one. I will post a picture of windows when i am home but i can show the cavity tray fit.

 

[wessex101]

It is not clear how the back of the cavity tray has been fixed, I suspect it has not. Therefore there is a risk that the back of the tray can flop forwards towards the outer leaf allowing water running down the cavity to get behind it and drip through the head of the window. That is the problem with just poking a length of polythene DPC in to the cavity rather than fixing it to the inner leaf or using a rigid proprietary cavity tray.

Another common defect is that they fail to put stop ends at the ends of the cavity tray allowing water to run off the ends and drip into the cavity rather than out of the weep holes in the outer leaf. Although this usually shows as damp patches to either side of the window head, I would imagine it is possible for the water to track across the underside of the lintel and drip through the window head.

I still think it is the cavity trays that are at fault.

 

[brum41]

Thanks that is really useful. He is coming back and has said he will resolve.