Venting Furnace Through Metal Roof

Run the vent pipe up through the roof and install a metal or pvc flashing collar over it.

Venting furnace through metal roof.

That s because the combustion byproducts are in a gaseous form so the gases can float up through the flue pipe and out of your roof. In many cases for existing homes this is the easier way to go. If your furnace has an afue rating below 90 percent it will most likely have a flue pipe that goes up through your roof. Match the vent pipe to the furnace maker s recommendations either sheet metal or vinyl.

Metal roofing works well with this because the metal is unaffected by heat not being able to pass through it and enter the attic. The other option of course is a vented attic which requires an equal balance of intake and exhaust vents. Installing some type of ventilation mechanism on a metal roof is not a lot different from the addition of vents to any type of roof. The water will condense and drip into the insulation below and perhaps into the house.

First you ll partially block your roof vent with the piping reducing the flow of cooling air through your attic. That depends on whether you have a standard efficiency or a high efficiency furnace. So which type of venting system should your furnace have. Should my furnace flue pipe go through the roof or the side of the house.

In this video i cover installing a roof boot for a vent pipe in a metal roof. Second during cold winters you ll be blowing warm moist air onto a cold surface the roof vent and roof plywood.