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Community and Q&A

Conditioned Spaces vs. Unconditioned Spaces

user-6789598 | Posted in Energy Efficiency and Durability on

To better understand the concept, I recently read the article “Cool Hand Luke Meets Attics” by Joseph Lstiburek and Martin’s “Creating a Conditioned Attic”. I think I understand, just for a bit of clarification please… What is the difference between a conditioned space and a unconditioned space? Also, I have mostly seen the terms ‘conditioned’ and ‘unconditioned’ describing attic space, but do they apply other spaces as well? Thank you.

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  1. GBA Editor
    Martin Holladay | | #1

    "Conditioned" means heated in winter. It can also (sometimes) mean cooled (air conditioned) in winter.

    "Conditioning" means changing the temperature of the air to make it more pleasant. We condition the indoor air in winter by warming it up. We sometimes condition the air in summer by cooling it.

    Usually, your living room is conditioned but your garage is not conditioned. (If you own a McMansion in Texas, however, you might have a conditioned garage.)

    Your basement or crawl space might be conditioned, or might be unconditioned.

    -- Martin Holladay

  2. GBA Editor
    Patrick Mccombe | | #2

    Conditioned describes a space that's heated and cooled with the rest of the house. An unconditioned space is not heated or cooled so it's the same temperature (roughly) as outdoor air. A semi-conditioned space is not conditioned to the same degree as indoor air, but it's not as cold or hot as outdoor air. Unconditioned and semi-conditioned spaces are outside the living space.

  3. user-6789598 | | #3

    Martin, I did live in Texas for a while and I have been in, never owned, a conditioned garage. I have also seen a conditioned dog house; don't get me wrong, I love my dog, but that was never going to happen for her. :)

  4. user-6789598 | | #4

    Thank you! That makes things so much clearer now!

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