Reducing humidity in tight house
I am in the process of finishing my house and have higher than ideal humidity levels and looking for advise as to the best way to overcome the humidity. I live in Massachusetts.
It is 700sqft single story with a full finished basement. On the ground level about 400sq of it is cathedral ceilings and the rest is normal 8ft ceilings. I have a semi finished loft over the 8ft ceilings with a 4’x4’ opening towards the cathedral ceiling. The ceiling is R42 closed cell spray foam and the walls are R36 open cell spray foam. I have radiant floor heat in the basement set at 68 degrees. On the ground floor I have mini splits set at 70 degrees.
I turned the mini splits on in July to dry the house out so I could instal the hardwood floors. I wasn’t living in the house throughout the summer so I don’t know the exact humidity levels but it was comfortable. Maybe a little on the humid side but nothing terrible it “felt” good inside. I moved in to the house in November and started monitoring the humidity levels then. I’m constantly around 50% humidity. If I crack a few windows and turn on the shower fan and the stove hood for a few hours the humidity will drop to around 42-45% and even that feels a ton better than the 50+
I would like to get the humidity down to 40% or even high 30’s. Since I don’t have any make up air for the house and I don’t have a central HVAC system I was thinking a dehumidifier. I don’t want the portable ones that I have to empty out every day. I was wondering if there was a permanent type of dehumidifier that I could either:
Install a permanent dehumidifier in the semi finished loft pulling air and venting into the cathedral space and finding a way to drain it
Install a permanent dehumidifier in the basement and run ductwork to pull air and return air to the floor below the cathedral portion of the first floor
Sorry for my lack of knowledge on the subject I don’t even know if such a dehumidifier exists or if it’s possible to hook it into ductwork I’m just looking for some input from people on the best way to deal with this higher than ideal humidity permanently. Thanks in advance
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