Where to cut roof vent for range hood
Hooking up a range hood. I have a roofer coming to cut the hole in roof for the exhaust cap. The duct work my son is going to run, roofer will not do that portion.
What the best way to assure the hole is cut in the best place for my son to run the ductwork? Should he construct the duct work in advance or allow the roofer to determine the best place accoring to the roof and then run it?