Furnace Venting Into Attic

You ll start to save money on your heating costs too and your furnace will perform closer to its indicated seer.

Furnace venting into attic.

The furnace has a stack which penetrates the flat roof and is about 3 4 above the roof plane. You ll see the concentric pipe used. That is because with an attic installation vents must go down into the thermal envelope to deliver warm air. The reason for this advantage is the fact that venting for your furnace requires less work in an attic than it does in other locations of your home.

In this video my hvac contractor gilbert rosipal from airrite shows us the inner workings of a 95 efficient gas furnace. Cut 1 inch deep slots a few inches apart along the top side. Now cut 2 inch deep slots. Unwrap the flashing from the vent pipe so you can work with it.

Bend these newly cut tabs in. Cut enough aluminum flashing from the roll to wrap around the vent pipe with an extra 6 inches to spare. Yes in fact this is the most efficient manner of providing air to your furnace. However the furnace is in an attic space which has no venting for warm humid air from house from soffits from hot roof etc to escape.

Unless you have a slab where the equipment would likely be in the garage venting can go directly through the roof instead of routing through an exterior wall making it much easier to install the duct work along the upper floor. If you re preparing to upgrade an old furnace it might be time to consider moving it back down to the ground level.