Water penetrating into cavity wall possible from the conservatory

Tech484

Hi,

Ive got a problem that Ive had for a couple of months now.

Water was getting inside the cavity wall and dripping from top of the window into the insdie of my conservatory.

I had re-pointing done on the wall and put in replacement felt.

This has sorted the upstairs (water was getting into the bedroom windows) but the water is still getting into the conservatory.

I knocked through the top of the kitchen window and with a torch I managed to look up the cavity wall. It seems that the water is pentrating where the wall meets the conservatory.

I have been told about 2 possible options;

1. Cavity tray above the lead flashing but I think the water could still get through

2. Replace lead flashing with a wider length to about 25cm so it covers more of the conservatory roof.

I also have been thinking if there is a way to fit some sort of a plastic covering (like the ones above windows) that are about 25cm in length that will drop the water from the wall over the lead flashing onto the conservatory roof just far enough that it safely goes down the roof and into the gutter.

Basically I want the water to by-pass the lead flashing and about 20-25cm of the roof of the conservatory.

By the way the conservatory is about 6m wide, with a flat centre and ridged sides.

I know its a long email but I wanted to put as much information in as possible.

Any opinions/ideas/recommendations would be highly appreciated!

iamcornholio

This situation is normally caused by lack of a stepped cavity tray above the conservatory roof

Rain can enter a cavity wall and when the conservatory was not there it drips out above the window or door largely unnoticed. Now that this is inside, you will see it

If the lead flashing is is sound, then it will likely be the lack of a tray

Retrospective installation is awkward and messy, so a better option may be to coat the area of wall above the roof with a silane water proofer (not silicone like Thompsons). And repoint as necessary first

If the water is definitely getting in between the frame and the wall then you need to deal with that via flashing or sealant

Tech484

Thats good advice and makes sense. However I'm just thinking, is there a ledge I can put up just above the flashing to 100% make sure water doesnt get in from the joint from the conservatory to the wall? I think the water might also be coming down the flashing and going into the cavity wall through some minor holes in the timber? Just want the water to go down about 20-25cm away from the wall!

ormus

with flashing its sometimes very difficult to find out where exactly the water is getting in.
its often just as easy to replace the whole lot and repoint/seal.
certanly quicker.

iamcornholio

If the flashing is properly pointed into the wall and dressed over the end rafter bar and sheet, then water will not get past it.

A ledge idea is pointless as the flashing should be doing its job, and then you are into a ledge above and then a ledge above the ledge and then a ledge above .....

Normally a leak from the exterior will be a lot more water showing a lot quicker and near to the underside of the conservatory roof

Water from the cavity takes more time to show and tends to exit lower down or just above the opening

Tech484

Thanks guys. I've noticed the flashing is not actually over the end rafter bar and sheet it actually goes just underneath the radter and sort of cuts off about an inch away from the wall.

With the heavy rains last few days I noticed the water was still dripping into the conservatory after it stopped raining, for about 5 to 6 hours atleast.