I have a 1500 sq foot bi-level which is 10 years old. The problem that I am having is the amount of humidity in the house. It is very well insulated.It also has an air exchanger. The basement has cement block walls with mostly ceramic tile on the floor. It has a totally finnished basement. The problem is at its worst when the temp is high 80 to 90 degrees along with high humidity. The humidity in the basement can run from 73 to 80%. The laundry room has cement floor and sweats so bad it changes colour from light to dark gray.The one room which has carpet even feels damp to the touch. I have been opening windows 2 inches at each end of the rec room to improve air circulation. I have been told that if I put an air conditioner in the house that will help bring down the humidity. Or I might buy a non-condensing dehumidification system. For your help I will make a donation to Habitat for Humanity
Answer:
Cold air holds more moisture than warm air and is, therefore, heavier. As air cools, it falls and keeps falling until it reaches the lowest level in the house. It cannot fall beyond the basement floor and that is where it has to be collected and pumped outside before that moisture gets a chance to condense in order to get rid of the moldy, musty odour and/or avoid it in the first place. A booster fan (250 CFM +) is available as a ‘pop in’ unit to fit 4”, 5” or 6” round heating duct. This can be installed in a totally separate duct line that is at least six feet from the nearest heat source. A timer on it will ensure that it operates only during the night (9pm to 9am) so cold, moist air it pumps out is not replaced by air that brings in even more humidity from outside. All joints and seams in the duct are taped and sealed for maximum efficiency and rather than a heating-type grill it should be a return air-type grill. To avoid having to core another hole in the foundation wall, this system can be vented, via a “TY” through the clothes dryer vent. Because none of the doors in the house go all the way to the floor, cold, moist air should find its way to that grill.
