Mold Inside Walls
Can mold live inside walls? Yes! Mold can live in a wide variety of places such as Attics with roof leaks or inadequate ventilation, Basements water problems ,Behind and under showers, tubs, toilets, and bathroom walls, Books, magazines, newspapers ,Carpeting and padding , Ceilings [from roof leaks],Clothing , Crawl spaces , Drywall in ceilings/walls, Heating/cooling equipment & ducts, Paper, cardboard & other paper products , Upholstered furniture , Walls (from siding, roof, & plumbing leaks), Wallpaper & behind wallpaper.
As long as there is moisture, food and warmth, mold can grow. The moisture can be in the form of high humidity above 50%, the food can be anything containing cellulose (wood, paper, cloth, leather) and molds can grow in a wide range of temperatures but average home temps are perfect. So inside of a wall is no problem for mold as long as all three criteria are met.