How to Get Rid of Algae Growth on the North Side of a House

On the Roof

• 1

  Pour 1 gallon of warm water into an empty pump garden sprayer. Add 1 gallon of chlorine bleach.

• 2

  Wet the algae-stained portion of the roof with the cleaner. Let it sit for 15 minutes.

• 3

  Scrub the algae spots with a stiff scrub brush until they disappear. Rinse the roof with clean water. Repeat as necessary until all of the algae is gone.

On Wood, Brick or Vinyl Siding

• 4

  Mix ¾ gallons of warm water, 1 qt. of chlorine bleach and ¼ cup laundry detergent into a bucket.

• 5

  Dip a soft scrub brush into the solution. If the stains are high on the house, attach the scrub brush to an extender pole.

• 6

  Scrub the cleaner onto the algae spots. Let the cleaner sit for 15 minutes and then scrub again until the algae is gone.

• 7

  Rinse the siding with clean water from the garden hose. Repeat this process as necessary until all the algae is gone.