This switch senses humidity and turns on the bathroom fan automatically! Good for basement and top floor bathrooms. If moisture doesn't make it up to the attic it can't do any damage!
I especially recommend this attached to a bathroom fan in moist basements. If you don't have a bathroom fan already, or even a bathroom in the basement you can still install a bathroom-type fan.
Just read that dehumidifiers can use more than 1000 kwh/year, so over $200 in VA. They just take out the moisture. And you have to empty out the reservoir. A fan will get fresh air into the basement. Fans use at most 0.05 kilowatts so they would reach 1000 kw in 2.3 years running full time.
If there are HVAC registers in the basement don't close them! And turning the fan to "on" instead of "auto" from your thermostat will also get the air changing out in the basement. Don't forget to keep the basement door open either, unless you have a return in the basement. Is that enough advice?! Hey, good air means good health for you and your house.
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