How do I stop mold from growing?

There are two ways to keep mold out of your home:

1. Keep your home clean because mold grows on surfaces contaminated with soil and grease.
2. Keep your home dry. If you clean up the mold, but don't fix the water problem, most likely the mold problem will come back.

How do I clean up and remove mold from the home?

To clean up mold, the area needs to be dried as quickly as possible. Mold will begin to grow in 24-48 hours, depending on the temperatures. Porous materials should be thrown away as they are difficult to clean. If the moldy area is less than a 3 foot by 3 foot area, in most cases the homeowner can do the job themselves. If there is greater damage, you may want to consult with a professional.

Materials such as glass, plastic, and metal can be cleaned and disinfected. Remove molds using a non-ammonia soap or detergent. Never mix bleach and ammonia. Surfaces where the entire mold cannot be completely removed should be treated with enough chlorine bleach to keep the surface wet for at least 15 minutes. Then rinse, and dry as quickly as possible. Disinfect by applying a solution of 1 cup chlorine bleach to 1 gallon of water. Keep the bleach solution on the surface for 15 minutes to kill the mold. Allow the solution to dry naturally.

What are Biocides?

Biocides are substances that can destroy living organisms. The use of a chemical or biocide that kills organisms such as mold (chlorine bleach, for example) is not recommended as a routine practice during mold cleanup.

In most cases it is no possible or desirable to sterilize an area; a background level of molds pores will remain – these spores will not grow if the moisture problem has been resolved. If you choose to use disinfectants or biocides, always ventilate the area and exhaust the air to the outdoors. Never mix chlorine bleach solution with other cleaning solutions or detergents that contain ammonia because toxic fumes can be produced.

Resources

• EPA Mold Remediation in Schools and Commercial Buildings
• EPA: Should I have my ducts cleaned?
• FEMA on Mold

Extension Publications

Preserving Family Treasures (PDF)
(Source: Kansas State University, April 1996)

How to Clean and Disinfect Tiles (PDF)
(Source: Kansas State University, August 1993)

Reducing Bacteria in Clothing and Textiles (PDF)
(Source: Kansas State University, July 1993)

How do I remove mildew?

Mildew grows when it is warm, moist and dark. Mildew grows on clothing, other textiles in the home, leather, books, paper, upholstery, mattresses, rugs and wood. Treatment varies depending on the type of item or surface you need to clean.

The following detail how to clean specific surfaces and items:

• Painted surfaces interior
  Scrub moldy surfaces with a solution of 1 cup of chlorine bleach to 1 gallon of water. A little detergent may be added to the solution, but do not mix bleach with cleaners containing ammonia. Rinse with clean water and allow to dry thoroughly before painting or papering.
• Bathrooms Scrub surface with a solution of 1 cup chlorine bleach, 1 tablespoon detergent that doesn’t contain ammonia and 1 gallon water. Keep the surface wet for about 10 minutes, rinse well with water and dry.
• Upholstered furniture and mattresses
  Brush surface mold away outdoors using a broom. Vacuum using an upholstery attachment. Discard the disposable vacuum cleaner bag. Use the services of a professional upholstery cleaner, or sponge the item with detergent suds and wipe with a clean cloth. Avoid getting the stuffing wet. Wipe the furniture with a cloth moistened with a solution of 1 cup denatured or rubbing alcohol to 1 cup water and dry thoroughly. Place the item in the sun for a few hours and air it thoroughly or use a fan and indirect heat to dry. If mold is growing deep in the padding of an upholstered piece, nothing will eliminate the mold except renovation or replacement.
• Carpet/Rugs
  Discard pads containing mold. It is nearly impossible to clean and destroy all the mold in a pad. It is best to hire a professional carpet cleaner or restorer to clean wall-to-wall carpet. If you try to save the carpet yourself, apply rug shampoo with a carpet shampooer according to manufacturer's directions. Expose mold growing on the back of carpet to the direct rays of the sun. Paint the carpet backing with a solution of 1/4 teaspoon chlorine bleach to 1 cup of water or other sanitizing product applied according to the label directions. Rinse several times. After shampooing and sanitizing, dry the carpet or rugs quickly by laying outdoors in the sun and wind, or use fans to speed up the drying.
• Clothing/Textiles
  To remove mildew from clothing or other fabrics, begin by brushing the mildewed area. It is best to do this outside. Dry the item in the sun if possible. If stains remain, colorfast items or items that can't be put in the washer can be sponged with a diluted chlorine bleach solution. This is 2 tablespoons bleach to 1 quart warm water. Test the fabric first before treating the entire item. White clothing can be soaked in the chlorine bleach solution, then washed, rinsed, and dried as usual.
• Books
  Stand books on end. Spread out pages to dry. Wipe off mold with a clean, dry cloth. After a few hours, stack and press to avoid wrinkling. Alternate opening and stacking until completely dry. Sprinkle with talcum powder or cornstarch on pages to absorb moisture. Books may be frozen until you have time to work with them. Place books in a closed container with moth crystals to stop mold growth.
• Leather
  Dyes used on leathers are very sensitive to numerous substances. Moisten a cloth with a solution of 1 cup denatured alcohol to 1 cup of water, wipe away visible mold and dry in circulating air.
• Painted surfaces exterior
  Scrub mold on paint with a solution of 1/3 cup detergent that doesn't contain ammonia, 1 quart chlorine bleach and 3 quarts of water.
• Roofs with asphalt shingles and fiberglass panels
  Use of a mixture of 3 parts chlorine bleach and 1 part water at the rate of 1 gallon per 40 square feet. The solution will damage metal rain gutters and plants, so control runoff and rinse surfaces that come in contact with the solution.
• Wood shingles, decks, untreated wood
  Scrub surfaces with a solution of 1 quart chlorine bleach and 1 ounce detergent in 3 quarts of water. Rinse thoroughly. If stain remains, increase the concentration of bleach to water and re-treat. Allow wood to dry thoroughly before painting or enclosing.