How to Clean and Get Rid of Mold on Windows with Bleach

Mildew and mold on your windows isn’t just unsightly and icky, it can be damaging to your home, and unhealthy for sensitive family members and pets.

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Use as directed.

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Bleach is best for cleaning mold and mildew.

It’s hard to beat bleach for cleaning ugly mold in your home. When used as directed, the sodium hypochlorite bleach active in Clorox® Disinfecting Bleach is highly effective at cleaning mold and mildew from a variety of bleach-safe surfaces, including glass window panes, vinyl or painted wooden window frames, grout and caulk. 

If you prefer a ready-to-use product instead of mixing up your own bleach and water solution, Clorox® Clean-Up® Cleaner + Bleach contains the same bleach active and is also effective against mold and mildew. Note that these products are not appropriate for use on aluminum windows as they will cause discoloration. If you aren’t sure what material your windows are made of, test first in an inconspicuous area.

If the bleach and water solution contacts any part of an aluminum window frame, rinse immediately with clean water.

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    Gather your supplies

    Steps to clean mold from windows

    1. Prep and ventilate the area

      Remove any window treatments from the window. Remove nearby rugs and place a towel under the window to protect the floor.

      Tip

      If desired, use a fan to circulate fresh air into the room where you will be working. Or if the room has multiple windows, open one nearby the window you are cleaning.

    2. Pre-clean surfaces

      If mold or mildew build up is heavy, first wipe surfaces with a wet microfiber cloth to reduce the amount of organic matter you have to deal with. Set the dirty cloth aside in the plastic bucket to wash later.

    3. Mix the bleach and water solution

      Wearing safety glasses and protective gloves, measure 3 cups of water into the spray bottle, then add 3 teaspoons of Clorox® Disinfecting Bleach. Insert the trigger sprayer into the bottle and tighten before adjusting the nozzle to spray a fine mist.

      Tip

      Bleach and water solutions must be made fresh daily.

    4. Clean the window

      Hold a cotton washcloth directly under the area you are going to spray to catch and wipe away drips as you are working. Spray the bleach and water solution onto the window; spraying additional solution as needed to keep the surface wet for up to 10 minutes. Wipe away drips with the washcloth and wipe the mold away with a microfiber cloth. In between sprays, use the toothbrush to gently scrub any mold out of corners or crevices.

      Tip

      Add dirty microfiber cloths and washcloths to the bucket as you work, switching them out for clean ones as needed.

    5. Rinse the window

      Soak another microfiber cloth with clean water and then wipe all the treated surfaces to rinse away any residual bleach solution.

    6. Dry the window

      Wipe the window dry with another clean microfiber cloth.

    7. Wash the cleaning cloths

      When finished rinsing and drying the window, immediately machine wash all the dirty microfiber cloths and washcloths together in the same laundry load. Select a heavy duty cycle and hot water, use a good detergent and add 1/3 cup Clorox® Disinfecting Bleach.

      Never mix ammonia or vinegar or any window cleaner with any bleach and water solution because hazardous gases can form.

    Frequently Asked Questions

    How long does a bleach and water solution last?

    Bleach and water solutions need to be made fresh each day that you use them because the bleach active, combined with your tap water, breaks down quickly into salt and water. Ready-to-use products, on the other hand, are formulated with a one-year shelf life when properly stored away from direct sunlight in a cool, dry place.

    What’s the best way to dispose of a bleach and water solution?

    The bleach and water solution can be easily disposed of by pouring it down any sink drain.