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How to get fresh air in finished basement without the condensation?

user-953356 | Posted in Green Building Techniques on

Purchasing a 1960’s built home that has a “finished” basement on Long Island (mixed Humid / 4). There is forced air AC upstairs, but none downstairs in the basement. There is oil fired hot water radiators both up and down. Looking for a short-term and long-term strategy. Will eventually undertake major renovation and do a better job looking at the whole house system.

I am familiar with ERVs and HRVs, and have chosen passive fresh air strategies (both bath fan/inlet and air handler connected) in our past homes.

The basement remains passively cool during the summer. My concern is if I go and cut in a dampered passive fresh air inlet, and put a timer on the bath fan, am I not going to get warm most air condensing on my cool basement surfaces? An ERV would help, but not that much.

What are some other retrofit strategies for getting fresh air into a finished basement?

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  1. GBA Editor
    Martin Holladay | | #1

    There are several ways you can lower the chance of condensation occurring on your basement walls during the summer:

    1. You can deliver conditioned air to your basement. Cooling air with an air conditioner has a dehumidifying effect.

    2. You can install a layer of rigid foam on the interior of your basement walls. This will raise the temperature of the outer surface of the wall, reducing or eliminating the chance of condensation.

    3. You can install a stand-alone dehumidifier in your basement.

  2. user-953356 | | #2

    Thanks Martin. I like the idea of pulling conditioned air from upstairs. This solves my immediate concern.

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