Sealing / Capping HVAC chase in attic

Old 02-19-15, 05:42 AM
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Sealing / Capping HVAC chase in attic

I'm in the process of air sealing the attic. The HVAC chase from the basement into the attic is unsealed at that point and very warm air is entering the attic from the chase. Should I seal / cap the HVAC chase as I would the chimney, perhaps with sheet metal or should the chase remain open at the top - in the attic. Sealing it is consistent with my air sealing but I'm concerned about the very warm air being trapped in the chase.

Any suggestions?
Old 02-19-15, 01:50 PM
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Seal the chase at the top.
The duct work is no warmer in your chase then in your walls and they're closed in.

Keep the heat you paid for in the house.
Old 02-19-15, 03:21 PM
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Hi Tony,
Also seal and insulate all ducts up there. Any air that escapes from that chase, ducts, or other leaks has to be matched by an equal amount of air leaking back in, somewhere. Think of sealing as a double savings.


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