To remove mildew from siding:

Wood Siding, Hardi-plank or Stucco - Use the following solution:

  • 1/3 cup all-purpose laundry detergent
  • 1 quart household chlorine bleach (must be fresh)
  • 3 quarts warm water
  • An alkaline cleaner such as washing soda or a cleaner containing trisodium phosphate can be added for extra cleaning. Follow package directions or use ½ to 2/3 cup.

Hose down with water, then scrub the surface with a soft brush. Avoid splashing on shrubs and other plants. Rinse well.

Commercial mildew remover/cleaners are also available. Do wear protective clothing – long sleeves, goggles, rubber gloves.

If your siding needs to be repainted, choose a mildew-resistant paint. The most mildew susceptible paints are latex paints, especially when linseed oil base primer is used. Acrylic gloss and semi-gloss latex paints are less susceptible to mildew than flat latex. Linseed oil base paints are also very susceptible. The least susceptible paints are exterior enamels. Special paints are available that contain a mildewcide.

BRICK- Once a year spray your brick off with the hose and a spray nozzle. A solution of one cup of bleach mixed with a gallon of water can be used with a stiff brush to clean this off. Don't use wire brushes or synthetic brushes--they can discolor the brick--use a natural fiber brush. Soak the brick before washing with the bleach solution.

STONE- To clean stone walls, fences or other structures, wash with a mild soap solution. Rinse well with clean water.