Basement ventilation
I would say I have a basement with 80% of walls insulated. There is a water heater heat pump, a sump pump, access to the crawl space which I think the door is properly sealed and an air source heat pump indoor unit installed. I don’t have fossil fuels at all in my house. And I’m using a dehumidifier most of the time. I recently turned on the heating mode of my indoor unit, there are not windows or vents on the basement.
Do you think I will have any problems with this conditions? My concern is that there is not air recirculation with the rest of the house or with the exterior. It looks to me that basement is complety sealed and putting heated air into the basement could bring some problems in the future. Please let me know your thoughts.
Thank you
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Replies
Unless extreme steps were taken, your basement is sharing air with the main level, but moisture loads are almost entirely dependent on your dehumidifier. The relative humidity settings on portable dehumidifiers are usually or always calibrated at about 68°F so if the basement is more like 55-60°, it should be set at about 60% RH to equal 40-50% RH on the main level and avoid moisture-related issues.
You might find it less expensive to heat your basement than to run a dehumidifier full time, especially if you finish insulating it.