Useful Stuff 2: Cleaning Vinyl Siding

Anyone that has been brought up on the coast or around a large lake or humid area knows what mold, mildew and algae is and what it can do to the vinyl siding on your house. Well, here is a mold mildew cleaning solution (notice the pun) to help remove mold mildew from your vinyl siding and make your siding come out like new.

Dave's Vinyl Siding Mildew Cleaning Formula

  • 3 quarts warm water.
  • 1/2 cup liquid bleach.
  • 2/3 cup trisodium phosphate, T.S.P.
  • 1/3 cup household liquid dish washing detergent (Ivory, Sunlight, etc.)

CAUTION: Do not mix with Mr. Clean, Fantastic or ammonia. These products can form a strong reaction with bleach, forming deadly gases.


  1. Mix all ingredients together in a 2 or 5 gallon pail.
  2. Apply on surface.
  3. Let stand 5-10 minutes.
  4. Scrub with stiff brush or broom.
  5. Rinse well with water.

If cleaning your vinyl siding before painting exclude detergent, rinse thoroughly with clean water, leaving no residue before painting.

When cleaning vinyl siding, start at the bottom and work up to the top, using a round-type (turk's head) brush on a long pole, rinsing the vinyl siding as you move upwards. If near plants, spray them with clear water.

Caution: wear rubber gloves and avoid contact with eyes.

Formula for removing green algae and black spots on concrete, asphalt, and pavement, wood, vinyl siding or aluminum siding, and white or coloured stucco. Use as above.

For the clear stain or finish on wood siding. I would recommend an oil base clear stain, not a latex. It should have UV protectors in it as well as a mildicide for controlling mold and algae. A light colour may cover better.


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