root wrote:
Breifly, the next-door neighbour has plastic, square guttering on
their side of the two semi's. We have the original round guttering
which feeds a cast iron outlet into the downpipe. The gutter leaks
badly where the square and round types meet.
It turns out that while the new guttering does actually have a
square-round adapter, this has merely been placed into the
downpipe's outlet with no sealant or physical attachment - it just
flaps around in the wind and rain.

While up t' laddter today I decided to see what remedies were
possible. The round outlet has two screw-holes in its base. The side
that goes to the half- round guttering is screwed onto the outlet,
the side that goes to the adapter isn't - it's just loose. This
appears to be because of a mismatch in the "systems": modern outlets
have a rubber seal to make a watertight joint, the original cast iron
outlet expects the guttering to be screw in and doesn't have a gasket.
The plan is to bed the loose end of the adpater into some adhesive
goop and possibly to drill a hole up through the adapter to form a
physical attachment (as opposed to simply an emotional one). Though
I'm a little dubious whether
a hole + metal screw would stand the test of time.

So, the question is: do I need to consider thermal expansion in the
joint? Would an adhesive ultimately fail due to movement, and/or
should a screw-hole in the bottom of the adapter be elongated to
allow expansion along it's length?


I've read this about 8 or 9 times and I've still no idea what you are on
about.

Where is the outlet?

Are you referring to the square - round adapter as an outet?

Why not just spend £25 and get yourself some new square gutter and clips and
join onto next doors' new stuff?