I have a new Broan QP 130 range hood and wish to vent it to the outside. My house is of metal construction with metal girders, studs, beams etc. and has metal siding and roofing. Ceilings are vaulted with no attic space. My stove is on an inside wall, four feet from an outside wall. Using a magnet, I found a metal stud right in the middle of the current hood. I believe the easiest thing to do is to vent thru the roof which is U panel. I am seeking advice before I start. The local building supply is not well stocked. I will need to order most stuff, like the vent flashing and cap.
Go big. Our house has a metal roof, and the roofer was afraid of putting too big a hole through it. So the 8" duct connects to a 4" hole with a stupid little flapper valve. As a result, the hood doesn't work nearly as well as it used to with the larger hole it went through before the new roof went on.