You were right JT, I went out and bought a dehumidifier, plugged it in and watched my meter increase in speed. It does take alot of the moisture out of the air though. My basement is finished with a gas fireplace which heats the whole house and the humidity down there is normal. It's on the main floor where I have the problem. Bathroom and cooking fans are vented to the outside. Would it help opening the damper on the main floor wood-burning fireplace even when not in use? Obviously I have no idea what to do! By the way, I live in central Ontario, Canada at the southern tip of Georgian Bay! Also, I went to Pathfinder and posted my question! Thanks for the link!