Dirt + Mildew — The Ugly Truth
A dirty, mildew covered window frame isn't just gross to look at but can cause real health concerns including sneezing, coughing, wheezing, difficulty breathing, headache and fatigue.
Though every home needs proper ventilation, cracks or gaps in window or patio door frames can let in too much cold air in the winter and too much moisture in the summer. These gaps also let wind borne dirt work its way into your home and provide the perfect breeding ground for mold and mildew.
Cleaning can provide some protection against mildew but virtually all construction materials and household furnishings can support the growth of mildew. The best defense is to prevent moisture by sealing windows and doors.
FACT: Mildew isn't just a winter problem. Mold can also grow where "conditioned" cold air blows against the interior side of a window or door.