How to Remove Outdoor Mold

Mold can grow indoors or outdoors, spreading and causing serious health risks, especially to those who have asthma or a mold allergy.

Mold and mildew spores can be brought into your home from outside
Many people take the necessary precautions to remove mold in their homes but forget about what's growing outside. Mold spores picked up outside can be brought into your home, making it important to rid the exterior of your home of mold and mildew. .

Remove any leaves and dead plants near the foundation and the exterior walls of your home.

Scrub exterior paint that has mold or mildew on it with a mixture of 1 quart bleach, 3 quarts water and 1/3 cup mild dishwashing liquid. Allow to dry and then apply a mildew-resistant paint.

Keep your roof clear of vegetation. Sweep your roof using a stiff broom to remove leaves and other debris, then use a garden hose to wash it down. Alternatively, clean your roof using 1 part bleach and 9 parts water to kill mold.

Seal outdoor wood such as decks and patios with a wood sealer to protect against the elements and keep mold growth at bay.

Scrub untreated wood with a mixture of 3 quarts water, 1 ounce mild dishwashing liquid, 1 quart bleach and 3 ounces trisodium phosphate. Rinse the area and allow to dry in direct sunlight.

Mix 1 part bleach with 4 parts water in a bucket. Scrub molded concrete with the mixture. Allow the concrete to dry.

Things You Will Need

  • Bleach
  • Water
  • Mild dishwashing liquid
  • 5-gallon bucket
  • Mildew-resistant paint
  • Paintbrush
  • Stiff broom
  • Garden hose
  • Wood sealer
  • Scrub brush
  • Trisodium phosphate


  • You may want to hire a mold inspector for a thorough evaluation of your home's exterior.

About the Author

Amanda Flanigan began writing professionally in 2007. Flanigan has written for various publications, including WV Living and American Craft Council, and has published several eBooks on craft and garden-related subjects. Flanigan completed two writing courses at Pierpont Community and Technical College.