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Community and Q&A

Options for HVAC for a residential renovation built in 1979 with no A/C

KGray | Posted in Mechanicals on

Hello all. New user here.

I am renovating a 2 story 2800 sq ft house built in 1979 about an hour west of DC–zone 4A. The house currently has original electric baseboard heat and no A/C so therefore no existing ducts. Half of the first floor is over a cellar (tight and dry) and the other half of the first floor is on slab. The second floor is a 1979 modular trucked in in two halves and bolted together in the middle of the house. The second floor is supported by a 12″ I beam through the center of the first floor and buried in a massive fireplace structure at on end which serves as the interior wall for a large cathedral ceilinged space at the far end of a long house. All very cool and retro Brady Bunch 70’s but giving all of my local HVAC guys a fit.

The problems are (1) getting any kind of traditional ducting around the massive stonework/fireplace structure and (2) getting ducts to both halves of the first floor. I don’t mind running duct alongside the I beam but that only allows me heating and cooling to one half of that floor because we cannot cut through the beam or the 2 X 10 center beams for the floor above resting on the I beam. So therefore I cannot heat or cool both halves of the first floor with a single duct run.

We have explored traditional high efficiency ducted systems and the Mitsubishi ductless system but neither seem to really solve the problem. Yesterday a contractor suggested the Unico high velocity system but he does not know a local installer.

Any comments or concerns with the Unico system in general? Any thoughts about creative ways to get out of this box?


Ken Gray

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  1. GBA Editor
    Martin Holladay | | #1

    You haven't presented a compelling reason why you can't just install ductless minisplits.

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