I like your forum and know that there are a lot of handymen.
I need to connect new gutter line with old one.
Somebody knows how to make gutter branch? Regular metal gutter.
For some reason there's no "roof" section of home questions over on the home section, but there is a repair forum. Maybe there is a roof forum and I just didn't see it...
My DH says that if it is a seamless gutter, then you can run the new piece inside of the other (downhill so the water doesn't come out of the joint) and pop rivet it in place. Or if it is an old type metal gutter, then you can buy a coupling to join the two together.