A dripping faucet or leaking drain provides moisture that encourages the growth of mold. The drip increases the humidity in the air, so spores start to grow in unseen areas. Dry the house by fixing these leaks. Clean any mildew you find growing in the house.
Ventilate the space
The smell is most likely to originate in rooms where water is present. Bathrooms, kitchens and laundry facilities are likely spaces. Open a window or turn on a vent when performing operations that produce moisture, such as taking a shower or boiling water. Consider installing an automatic timer on vents to keep them operating at least 12 hours daily. Air conditioning also helps to reduce the humidity in the home. When homes have wooden floors, foundation vents should be opened during the winter to expel the moist air and closed during the summer to keep the humidity out.
Absorb the odor
Activated charcoal, baking soda and sidewalk chalk are all powerful odor absorbers. Place them in the areas where the smell is most noticeable. Commercial moisture and odor absorbers are also available.