Furnace Flue Pipe On Roof

For many homes a gas furnace is the preferred heating device it has proven to be an efficient and reliable way of meeting household heating needs over the years.

Furnace flue pipe on roof. If your furnace has an afue rating below 90 percent it will most likely have a flue pipe that goes up through your roof. Horizontally through the sidewall or vertically through the roof. The pipes can be set in two ways. The opening around a furnace or water heater flue or chimney can be a major source of warm air moving in the attic.

Because the pipe gets hot building codes usually require 1 inch of clearance from metal flues 2 inches from masonry chimneys to any combustible material including insulation. Next take the length of cut pipe and push it into place so that it lines up with the connections. Furnace vent pipe installation code gas furnace venting codes furnace exhaust pipe code furnace flue vent code gas furnace exhaust pipe regulations. Run the vent pipe up through the roof and install a metal or pvc flashing collar over it.

When compared to the natural vent this one is more flexible although it is also costlier. In contrast modern high efficiency condensing furnaces exhaust much cooler gasses and need only plastic pipe materials such as pvc cpvc or abs for their exhaust vents some high efficiency furnaces also include a plastic pipe for intake area and all types. Match the vent pipe to the furnace maker s recommendations either sheet metal or vinyl. Crimp one end of the pipe using the pipe crimper to smooth it down.

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. A gas furnace uses a double wall flue pipe for its vent. The inner liner carries the furnace s exhaust fumes outside and the outer liner insulates and protects the inner liner. Usually a galvanized metal pipe sized to accommodate the furnace s output of british thermal units the flue connects to the furnace combustion chamber and is typically routed up through the ceiling and attic terminating at a hooded vent on the exterior of the roof.

Traditional gas fired forced air furnaces produce hot combustion exhaust gasses and therefore need metal vent pipes or chimneys. Push the pipe into place. Push the connections from the existing exhaust pipe over the pipe. Stove pipe inscreasers and reducers.

Then use your snips to cut a matching length of flue pipe. Furnace flues require special sealing techniques. The furnace flue is the pipe that exhausts these gases away from living spaces.