Aluminium Gutter - fixing downpipe

Aug 25, 2025 Last reply: 10 months ago 11 Replies

I had some aluminium gutters fitted about a year ago, and the the plastic downpipe has come loose from the main gutter. Rain (if and when) just dribbles down the wall.



I phoned the installer about a month ago - they said they'd get on it but haven't, yet.



On closer inspection I'm not sure about the installation. The gutter is one long piece, about 15m, with what seems to be a hole drilled in it to accommodate the downpipe. I've no idea how the downpipe is fixed and sealed - there's no T-piece that you'd normally see.



Anybody with experience of this sort of thing? A couple of pics here:



formatting link
The red circle is where the downpipe is located - I couldn't lean out far enough to show the hole.


That looks decidedly odd. Are you saying that the downpipe has come away and you can just see a hole in the gutter where the downpipe "fits"? There should be an extension down from the gutter which the pipe fits over. If there isn't one, that's not right.

How long is the downpipe? If all else fails and you can get to the top of the pipe (or can get the pipe down to ground level), you could run some black silicone cement round the top of the pipe and push it up so that it forms a seal between the downpipe and the gutter. It'll have to be held in place somehow for at least 12 hours to dry reasonably well. At least it would stop water from the gutter pouring down the wall when it does rain until a proper repair can be done.

Yes - it hasn't fully exposed the hole, just shifted over an inch or two. The photo isn't that clear as I'm taking it from the ground, looking up.

That's what I thought.

About 3 metres.

Yes, could do, thanks.

For some reason Safari will not display your photo. The only other continuous gutters I am familiar with are wooden gutters where a hole is drilled to match the Downpipe, in that instance a flanged lead sleeve is inserted to direct the flow into the downpipe. A good builders merchant should stock them even a plumbers merchant

Richard

Found an example

formatting link

Richard

Even a plastic version but may not suit the profile of your guttering although a little application of heat might enable you to form it appropriately

formatting link
Richard

+1.

But you need ASA or ABS. PLA wont last 5 minutes under sun

3D printer isn't cheap. nut by the time you tot up all those little expensive broken plastic thingummys you need to buy off ebay, it starts to pay for itself.

Thanks - that's got it. I found some more pictures I took when I had the opportunity to get up there. I've posted them - hopefully they're showing now.

A couple show the arrangement at the other end of the gutter. Something like this:

formatting link
is inserted. My pics show a dome leaf strainer above the hole in the gutter.

The other is the offending part before the downpipe was fitted, showing a sleeve over which the downpipe would fit. Somehow, that's become dislodged, or maybe snapped.

Thanks for the pointers.

I'm sure a gutter person would know where to get replacement outlet insert but none showing in my searches of gutter shops.

These are some scraps from the old system that was on the house. The gutter presently in use is a bit larger dimensions, but the operating principles remain the same. I keep scraps like this around, for odd projects.

One self-tapping screw per side goes into the down-pipe, where it fastens to the plastic adapter. That connection is not load bearing. The vertical run of pipe is held to the wall, with rawl-plug and pipe-strap, and a screw through the two arms of the pipe strap, keeps the pipe fastened to the strap. And the screw behind the pipe, holds the strap to the wall. And that strapping, every so many feet on the vertical run, should be mostly holding the pipe to the adapter, so the four screws don't have to work too hard.

[Picture]

formatting link
The plastic adapter is bedded in caulk where it is seated. While a silicon seal (the modern kind, not the acetic acid kind) can bed the adapter, there is also a petroleum-based product intended for that particular job. The installer used a few tubes of that up, before the job was done. But not every point in a system needs caulk, and some parts need to come apart for cleaning and maintenance. And gravity (mostly) ensures the water goes where it is supposed to go.

To cut a hole for the plastic adapter, in the aluminium one-piece gutter, you can first make a template to fit the adapter shape. While on the ladder, run your pencil around the template, to transfer the shape to the gutter. Drill a pilot hole, then put the head of your nibbling tool through the hole, and you can cut a reasonably precise irregular hole in the gutter. Because it fits the plastic adapter snugly, there is less need to be driving screws into the top of the adapter.

formatting link
Paul

That seems to be the system I've got. The mystery is where the outlet piece has gone.

Yes, I'm not sure what if anything the installer used to seal the outlet.

Thanks. The hole is already there in my case.

Your gutter looks exactly like mine - apart from the colour (mine is brown). About 2/3 of the way along the gutter shown on your photo, there is an aluminium spigot pointing downwards. This will have a flange at the top which is riveted and sealed to a hole in the gutter. The plastic downpipe is supposed to be a push fit over the spigot and, provided that it is held firmly and cannot slip down, needs no further sealing. It looks as if your downpipe has come away from the spigot, and if flapping around in the breeze!

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required