Who is this person making such a brainless suggestion? Your othe

I am going to whip his A--. Such a large piece put on top will surely be blown away by wind in no time.

Correct way: cut out the flat part of new boot, put tar over the old one and glue the new one over the old one. Make sure there is no space between the two, don't cut it too small. Then tar at the joint of new boot and pipe as in a normal installation.

This is just a hold-on fix, next time you change root you got to get a new one installed in the right way.