We have a 1000 sf basement with 3.75 sides undergrade. We have been experiencing humidity and mold problems since we moved in in July. We beleive all moisture problems from outside source have been solved. We live in Alabama and it has rained most of June and July. We have a 5 ton Trane with varible speed blower. The main level of house is fairly consistent RH at 48-50%. The basement remains between 63-70% even with portable dehumidifier running. I have considered many option from additional unit to control RH to the purchase of dehumidification system. The problem with the portable is the noise and heat. Please make recommendations. I would like to have a neat installation without noise and heat. If one can go into existing ductwork would be a plus.