[azasadny]

Yep, a humidifier is a "band-aid". Get to the root of the problem and get some additional ventilation in there. Can you tie in an exhaust vent in the closet with the bathroom exhaust vent and exhaust it out the roof? We have a Broan MP100, which allows up to four 4" exhaust ducts to connect to a "ramote" fan motor that exhausts it out a 6" exhaust duct. We reduced the 6" exhaust to a 4" and have two bathrooms and two showers using it and it is very effective...