If your home's gutter system is clogged and mildew stains have formed on some of the shingles on the rooftop due to moisture that has accumulated, unclog the gutter system and clean the roofing materials by completing the following steps. Afterwards, keep the gutter system and rooftop maintained throughout the year to prevent mildew from forming again.


  • ladder
  • hand rake
  • handheld scrub brush
  • detergent
  • water hose
  • lawn and garden sprayer
  • oxygenated bleach
  • long-handled scrub brush
  • rake

Unclog The Gutter System And Clean Its Interior

Set up a ladder next to your home, near the gutter system. Remove leaves and debris that are clogging the gutter system with a hand rake. If any dirty residue is stuck on the surface of some of the gutter system, eliminate them with soapy water and a handheld scrub brush. Insert the tip of the scrub brush in the downspout and move it up and down to dislodge any materials that are stuck inside of it. Rinse the gutter system's and downspout's interior with a water hose when finished. 

Remove Mildew Stains From The Shingles

Disconnect a lawn and garden sprayer's tank and add equal amounts of water, detergent, and oxygenated bleach to it. Oxygenated bleach is better to use than chlorine bleach because it does not contain harsh chemicals that are found in standard bleach, which could cause permanent discoloration to the shingles. Mix the components added to the tank by turning on the machine's agitator for several minutes.

Reattach the tank and carry the machine up the ladder. Aim the sprayer's nozzle at the mildew stains and squeeze the machine's trigger to emit a liberal amount of the cleaning solution. Use a long-handled scrub brush to loosen the stains. Add more of the cleaning solution if you have a difficult time removing any of the stains. Rinse the shingles off when finished.

Maintain The Gutter System And Rooftop

Inspect the gutter system and rooftop periodically throughout the year. It is a good idea to check the condition of each one after severe storms. Remove large pieces of debris by hand or with a long-handled rake or scrub brush, because the foreign materials can damage the roofing materials and cause a blockage inside of the gutter system. Check the end of the gutter system to make sure that it is lined up properly so that water will drain away from your home.

Rinse the rooftop, the inside of the gutter system, and downspout with a water hose. Completing the same steps at random times throughout the year will prevent stains on the shingles and clogs inside of the gutter system. Contact a roofing contractor in your area for more info or assistance.