I have a 10 year old conservatory. A leak has developed from under the glass where the glass sits on a seal. From what I understand the glass sits on rafters that has a rubber gasket. the weight of glass plus the compression of the outer cover is supposed to seal it and the cover on top is supposed to also have a gasket preventing water ingress. I need to go up on the roof to check, but wanted to know could be the possible causes? and are there any fixes if the seal is leaking?
Conservatory Glass Leaking
- Thread starter john2k
- Start date
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Its always tricky.
You need to find where the leak is getting in rather than where it exits internally.
Is the water coming in at the ring beam at the bottom of the rafter?
Generally if water gets in between the glass, it does so at the top and runs down until it hits an obstruction.
Ive not known water to get in the side of the capping bars.
What should happen is that the rafter gasket has thin ribs on it like a wiper blade so the water runs downwards like a channel. Most conservatories are designed with the rafter gasket runni gpast the fascias at the bottom so any water or condensation runs out.
I would check first to see if you have any displaced lead flashing at the top.
If you have roof vents, then that is a common leak point -its where the glass if fitted in an H section below the vent.
If you talking about leaks from a hip or jack rafter, then the leak may be where the capping bars meet.
You need to find where the leak is getting in rather than where it exits internally.
Is the water coming in at the ring beam at the bottom of the rafter?
Generally if water gets in between the glass, it does so at the top and runs down until it hits an obstruction.
Ive not known water to get in the side of the capping bars.
What should happen is that the rafter gasket has thin ribs on it like a wiper blade so the water runs downwards like a channel. Most conservatories are designed with the rafter gasket runni gpast the fascias at the bottom so any water or condensation runs out.
I would check first to see if you have any displaced lead flashing at the top.
If you have roof vents, then that is a common leak point -its where the glass if fitted in an H section below the vent.
If you talking about leaks from a hip or jack rafter, then the leak may be where the capping bars meet.
I will get up on the roof to have a look in a few hours. But from what I can see it's basically entering from somewhere below a roof window and then it's somehow made it's way into the rafters that run down and the water is channelling straight down from there to the bottom and exiting from all different locations above the patio doors
If your roof vent is a typical design, it will be the same width as the glass panel below. It would've been fitted at the same time as the glass.
The roof vent is put in place, then the lower glass is slid up to it and into an H section. Finally the capping bars run all the way up, over both glass and vent.
One solution is to unscrew the roof capping bars, fit some aluflash flashing and some lead mate
1 strip across, below the roof vent and under the capping bars with the lower edge 15mm or so onto the glass below. A bit leadmate across the top edge to allow the water to run over. Then capping bars back down.
Im only guessing, based on the type of roof vents Im used to. If so, the H sectin is vulnerable to leaks, either driving rain upwards, or water running down, goes up over the H section lip and gets in.
https://www.toolstation.com/shop/p57516?searchstr=aluflash
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So the rain has stopped and i went up on the roof. I just cannot visually see anything wrong from outside. Basically the vent piece has a flat section below where the glass slides up on to and sits on. The water seems to somehow be seeping underneath the glass below the vent and 3 small sections of water seem to run all the way down the window instead of falling straight down and go to the bottom of the glass and then drop down. I just poured water from the outside over this and just can't seem to get it to leak now. So will have to wait for rain to come back. One thing was that it was very windy with the rain today so I am wondering could the wind have blown the rain up? But we've had lots of windy rainy days in the past and no issues
Below are some pics. The first is from the outside. The second pic is from the inside and i've drawn arrows show where the water is seeping in from and running down that arrow direction on the glass til it gets to the door.
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I poured quite a bit of water over the roof but couldn't get it to drip on the inside. But I just had an idea to stick kitchen tissue into the gap from inside and run it along the trim where the glass is sitting and the tissue absorbs a lot of water leading me to believe that when im pouring water from the the top small amounts are seeping in to wet the gasket but not enough to create a drip. Whereas heavy rain for long time would have allowed water to get through. I tested the tissue on the same type of trim on the other side where I have another roof window and it doesn't soak up there. Could I not apply some sort of seal/ tape from the vent while vent over the glass creating a slight overlap? The method you mention, how do you actually remove the roof capping bars etc? The glass sits on the flat section below the vent and is there a flat piece of plastic on top of it to seal it? Is there a way to remove this trim and reseal it?
Yes you could do that. It depends whether the leak is just the H section abd not where the capping goes over the H section.
I dont know the type of roof system you have, maybe the capping bars are difficult to remove. In which case you could put flashing in between the cappings across where the Glass goes in the H section.
Thanks @Notch7
In the pic below, I have drawn a arrow pointing to the trim that seems to cover where the glass sits on the vent. I took the pic with the window a little open. Can the water be seeping in from the top? but if i remember correctly when the window is closed it overlaps over it so water shouldn't get on it except from the sides. How does this piece create a seal? Can I not remove this piece and maybe put sealant underneath and then push the piece back in?
In the pic below, I have drawn a arrow pointing to the trim that seems to cover where the glass sits on the vent. I took the pic with the window a little open. Can the water be seeping in from the top? but if i remember correctly when the window is closed it overlaps over it so water shouldn't get on it except from the sides. How does this piece create a seal? Can I not remove this piece and maybe put sealant underneath and then push the piece back in?
Thanks @Notch7
In the pic below, I have drawn a arrow pointing to the trim that seems to cover where the glass sits on the vent. I took the pic with the window a little open. Can the water be seeping in from the top? but if i remember correctly when the window is closed it overlaps over it so water shouldn't get on it except from the sides. How does this piece create a seal? Can I not remove this piece and maybe put sealant underneath and then push the piece back in?
TBH, I dont know -it doesnt look like a separate trim. Its a bit tricky to visualise the context without a pic showing a bigger area.
Ive minimal experience of upvc roofs since I only build in timber......hopefully a upvc guy will be along soon with better guidance.
I'll try and take a pic of a bigger area tomorrow. It's a bit hard being on the roof and taking pic
If it's not a separate piece, then I wonder how the glass ends up under there? I take it, it will slot into it then. If that's the case is there some sort of tape I can apply over it and overlap it? Needs to be something that will bond well
By H Section, do you mean the piece that runs horizontally were the glass goes into and the window vent goes into something like the link below: https://www.diy.com/departments/sil...et-glazing-bar-4m-x-25mm/5060521032275_BQ.prd
It it might be a H section which will mean that piece at the top cannot actually be removed. But on the example above the two sections are separated so if water got in from the to it cant get to the glass below unless it seeps in from the side. If it's a H section then removing and sealing the H section will be quite tricky. How does the H section actually seal? Can I not put a bead of external sealant over it? What about cleaning it thoroughly and maybe applying vinyl wrap over it so it just overlaps allowing water to run over the vinyl?
I'm come across the following tape, the description seems good. Wondering If I can just apply that overlapping the white piece that joints the vent and the glass together?
https://www.bcprofiles.co.uk/everbuild-clear-waterproof-tape-50mm-x-33m/
https://www.bcprofiles.co.uk/everbuild-clear-waterproof-tape-50mm-x-33m/
Also came across the following gorilla tape:
https://www.toolstation.com/shop/Ad...Tapes/sd2420/Gorilla+Clear+Repair+Tape/p57078
Wondering if I apply this on top over the section where the window and the glass meet. Overlapping both sides. Then technically water should just run over it and down the glass below. Only issue would be the two side corners if there is a small gap that will be enough for water to get under the tape.
https://www.toolstation.com/shop/Ad...Tapes/sd2420/Gorilla+Clear+Repair+Tape/p57078
Wondering if I apply this on top over the section where the window and the glass meet. Overlapping both sides. Then technically water should just run over it and down the glass below. Only issue would be the two side corners if there is a small gap that will be enough for water to get under the tape.
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