Expanding foam weather/water proof?

Unless they have applied some kind of coating then certainly the latter. The stuff doesn't like exposure to the sun at all.

shaun presented the following explanation :

From the ground, they do not seem to have done and the joint is not even filled up with the stuff.

It will start yellowing & crumbling within 12m, if in direct light. Paint over with black mastic would do for a good while, but for a paid job I'd expect a proper connector.

Good in the right places...

And this is not one of them!

Nope it is a total bodge (the foam breaks down with UV exposure and is not totally waterproof to start with). Get the neighbour to have em back to do it with the correct connector!

John Rumm explained on 05/09/2005 :

It certainly looks like a bodge. I just wanted a second opinion on this.

Thanks all.

I may well be wrong but I have not seen connectors for adapting different rainwater systems.

Ideally, a semi needs to have the guttering replaced as an entire building. If that were not possible then the installers should have said that because it's one building they could only replace the guttering with the same stuff as yours.

You can certainly get round (and ogee) section to square section adaptors. My neighbour had his steel ogee gutters replaced a few years ago with PVC square section. Must admit I did not pay much attention at the time, but when I replaced my guttering recently I found two such connectors joining the old to the new.

Yip it does not like sunlight. The escaped blobs of the stuff near my soffits went from blue to brown in a couple of months and when I finally went up to clear up, the brown stuff just powedered in my hands. So not really any good outside in the light.

They are available (one supplier below):

I forget the name of the company but at one of these self build shows there was a company that produced guttering and the guy there told me they could supply various adaptors from their new gutters to connect to other makes, new and obsolete.