How to seal aluminium internal gutter butt joint on Gazebo !

eddie · 20-10-2025 12:36PM #1

Aluminium complex profile on Gaszebo is used as water catchment / gutter. Face to face butt joint in profile ( approx 80mm overall length ) fails so seal. The seal can only happen on inside of profile and as profile is complex - tape of any description is not suitable.

I have tried a few epoxy attempts, and then tried the standard resin type seals, but they all fail.

I can clean the inside, reasonably well and I am looking for a "paint on" solution.

Any recommendtions.. thanks..

Mr321 · 20-10-2025 05:34PM

Tec 7 sealant

The Continental Op · 21-10-2025 11:23PM

I know the OP doesn't want to hear this but Aluminium tape can be shaped to fit the most intricate shapes. If you put the tape on so there is a bit of slack in it you can work it down so it all goes flat against the surfaces. You can also add more than one layer or even use multiple narrow strips where each strip covers one part of the shape.

iirc epoxy won't bond well to oxidised aluminium and you need to sand it before using any epoxy/resin type coating.

eddie · 22-10-2025 08:10AM

https://www.boards.ie/discussion/comment/123926586#Comment_123926586

Thank you for the input - I agree and wish I could get it to work. I tried 3 times.. the profile is approx 25mm wide by 35mm deep not quite U shaped and at the bottom is a 12 x 8mm rectangulor recess.. … no tool I have or made can get the tape into that.. PLUS the whole side of the gazabo butts up to a gutter pipe on the house with just a 70mm gap to get your fingers tools into and down the profile… I need some compound I can paint on liberally………. The outside of the profile is surrounded by re-inforcing plates.. etc so no use..

The Continental Op · 22-10-2025 09:01AM

I'd go one better than paint on, spray on. Can't find the one anywhere that I've used in the past on gutters it was a traditional bitumen based spray on mastic on the new ones seem to be rubber or acrylic based.

So this would be something like I'd try. If you can find a clear one then once you know what it looks like on the inside you might spray the outside to improve the seal?

Then if the cracks are really fine I use Captain Tolleys Creeping Crack Cure https://www.amazon.co.uk/Captain-Tolleys-Creeping-Crack-sealer/dp/B003T6EJ9A/ . Works great on the car where I get leaks into the boot.

Neither will be permanent fixes and will need redoing each year.

Then you could try something that isn't used for crack filling at all but does penetrate between components and seals. Thats Owatrol. You can find it in spray form if that helps. I will get between any gaps in the reinforcing places and seal them. Then a mix 50/50 of Owatrol and Aluminium Oxide undercoat paint might also be useful. All depends on the size of the gaps you are filling.

eddie · 22-10-2025 10:31AM

https://www.boards.ie/discussion/comment/123927079#Comment_123927079

Cool will certainly put on short list..

eddie · 22-10-2025 11:23AM

https://www.boards.ie/discussion/comment/123926944#Comment_123926944

WhatsApp Image 2025-10-22 at 12.19.10_8ba77de5.jpg

Since I dont smoke I dont have a "back of a fag packet scribble " so this is next best thing…

The Continental Op · 22-10-2025 11:44AM

How are those two positioned in relation to each other.

If all else fails cut the mickey mouse gutter off (along its lowest point) and fix up a real gutter.

eddie · 22-10-2025 12:24PM

https://www.boards.ie/discussion/comment/123927601#Comment_123927601

Close - approx angle as shown and maybe 70-80mm apart - Mickey mouse gutter doubles as support frame for Gazebo

The Continental Op · 22-10-2025 01:59PM

Excuse me if I'm asking stupid questions :-) Sometimes something comes of them.

Can you change the main gutter to a really wide profile one so it goes under the Gazebo gutter?

eddie · 23-10-2025 04:30PM

https://www.boards.ie/discussion/comment/123928040#Comment_123928040

Never heard of a stupid question in my life… I ask questions ALL the time, basic as possible.. …

Sketch was from my memory as I was down country for a few days.

So the (House ) gutter is actually overlapping and approx 100mm higher than the Gazebo Gutter.. so heights cannot be adjusted the idea was that both gutters ( over lapping ) would ensure no water on the threshold to the house and it works at all point along the side of the gazebo except at the joint, where it leaks bad and of course that is exactly in the middle of the threshold.. so you step out on to the patio , into a big wet area..

A good sealer should do it,, it is only the awkward profile that is the issue, but I think the proper sealer WILL solve it..

The backup plan is that as there is a continuous gazabo gutter linked on all 4 sides as one and it is perfectly level and 4 down pipe locations ( 1 on each corner but only 1 in use.). I can blank it 200/300mm of the bothersome side and allow the other sides to deliver the rainwater to the down pipe.

The Continental Op · 23-10-2025 10:04PM

So is part of the problem getting your hand in to seal the joint?

eddie · 25-10-2025 09:51AM

partly. But mainly getting a deal into the box section at the bottom of the profile. Plan is to get jointing CV impound that set in wet / poor conditions and fill the bottom rectangular section of the profile and then the joints on the sides. So looking for best joint medium.

How to seal aluminium internal gutter butt joint on Gazebo !

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