venting from mobile home through new metal roof

jeanmoon

I want to put a metal roof onto my existing mobile home roof. My gas furance vent is not tall enough to go through the new metal roof. I have been told that a mobile home gas furnace vent has both the intake and out-take in the same design; a pipe within a pipe, that is why my pipe is 12 inches in diameter. I believe it is this type of exhaust & intake system.

I have also been told that I only need to bring the exhaust pipe through the new metal roof and that the intake pipe can draw its air from inside the roof. I have end vents on both sides of my mobile home allowing it to draw enough air. My question is; is this feasible and is this safe. I would not want to have it catch fire.

-Pjackso

I don't know about mobile home exhaust vents. But if you're correct (pipe-within-a-pipe), then I would recommend you have both pipes thru the roof. Having a hidden (blind) intake doesn't seem smart from a maintenance or accessiblility standpoint.

Also, I think mobile homes can only have 1 layer of roofing. So plan on a tear-off. I've seen old mobile homes with multiple layers, and the roof sags between the rafters with the extra weight. Looks terrible.


Note: I am not a roofer.

jeanmoon

You are right about making acessibility very difficult. I was trying to cut the size of the vent down going through the new roof from 10 or 12 inches to either 4 or 6 inches.

The new roof will be built as a truss, and I am planning to use it to help hold the ceiling in place. I also have 2x6 walls to support the weight. Thanks for your thoughts. It helps.