How to Remove Exterior Mildew Stains

Person spraying liquid on a wall with mildew

Make sure to remove any mildew stains before you paint your home's exterior.

For Best Results:

Make sure to dampen the areas to be cleaned prior to applying the cleaning solution

Allow sufficient time for the cleaning solution to work (10 - 15 minutes).

  1. Step 1
    Using a garden hose or a pressure washer, wet the mildewed area with water.

  2. Step 2

    Using a pump sprayer, apply BEHR PREMIUM® All-In-One Wood Cleaner to the mildewed area.

  3. Step 3

    Reapply the cleaner as needed to keep the surface wet. Allow the solution to remain on the surface for 10-15 minutes. Scrubbing may be required on severely stained surfaces.

  4. Step 4

    Thoroughly rinse the surface with water. Allow it to dry.

Suggested Tools & Supplies
  • Bucket
  • Hose
  • Ladder
  • Pressure Washer
  • Protective Apparel
  • Pump Sprayer
  • Rags
  • Scrub Brush
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