We have a metal roof-over on a mobile home that was raised 18" on back side slopingdown to the front and has vented sofit all the way around on 3 sides. The man did not put the plumbing pipe vents through the roof He said because it was open all around the bottom we wouldn't need them and the ends are closed in. I notice we get a lot of ice build up and it hangs off a foot or more and gets really thick and heavy. The snow stays on where as other mobiles with a peek roof or higher slope like ours it slides off. Last year shut heat down were not here in the winter but worry about the heavy ice on the addition too. It slopes off the back side just below the 18 inch rise and has no vents either.
Do I need whirrly vents put in or can I try and vent the ends? Are the hotwater and sink vents causing the ice build up?