10-29-2014, 04:00 AM
The video has a good install technique, just did not highlight one preplanning point, make sure that your opening is between rafters/trusses (it is shown that way, but does not show HOW), some will go into the attic area and center the outlet circle cut between the rafters/trusses & drill a small pilot or drive a self tapping screw in the center so that when you cut the metal roof, it is in the center of the circle, with no rafter/truss obstructing or getting cut!
I have one other comment on this video, the OTHER vent that was installed in this video will have problems with damming, as it has the entrapment areas at the valleys on the upper arc of the flashing, as I mentioned. The flat section I referred to from HPM would cap that whole area, like the flashing used in this video, but take it to a lower elevation on the roof...then you "shingle" in the vent flashing & finish the bottom as shown...
There are some install videos that show cutting sideways into the roofing & slipping the flashing under then gobbering the whole sliced up area with caulking...any roofer knows, that is a future failure point, as you are just relying on the caulk for your water tightness, and the slit edges WILL move & most likely expand over years of thermal changes...
I have one other comment on this video, the OTHER vent that was installed in this video will have problems with damming, as it has the entrapment areas at the valleys on the upper arc of the flashing, as I mentioned. The flat section I referred to from HPM would cap that whole area, like the flashing used in this video, but take it to a lower elevation on the roof...then you "shingle" in the vent flashing & finish the bottom as shown...
There are some install videos that show cutting sideways into the roofing & slipping the flashing under then gobbering the whole sliced up area with caulking...any roofer knows, that is a future failure point, as you are just relying on the caulk for your water tightness, and the slit edges WILL move & most likely expand over years of thermal changes...