I am not that knowledgeable with mold. On my exterior front door by the head and the door stop I have mold growing. I checked the drywall and it doesn't seem to have any water damage. I was thinking to wipe away the mold but I thought it might comeback twice as worse so I wanted to check and see what the community had to say.

  • What kind of mold? – John Dec 31 '15 at 13:07

Background Information

There are really only four things necessary for mold growth:

  1. Mold Spores
  2. Mold Food (Organic Substance)
  3. Appropriate Temperatures
  4. Considerable Moisture


The best way to control mold growth, is to control moisture. One good resource available to you is the Brief Guide to Mold, Moisture and Your Home from the US EPA. The US CDC has the following recommendations for decreasing mold exposure:

  • Never mix bleach with ammonia or other household cleaners. Mixing bleach with ammonia or other cleaning products will produce dangerous, toxic fumes.
  • Open windows and doors to provide fresh air.
  • Wear non-porous gloves and protective eye wear.
  • If the area to be cleaned is more than 10 square feet, consult the U.S. Environmental Protection Agency (EPA) guide titled Mold Remediation in Schools and Commercial Buildings. Although focused on schools and commercial buildings, this document also applies to other building types. You can get it by going to the EPA web site at http://www.epa.gov/mold/mold_remediation.html.
  • Always follow the manufacturer’s instructions when using bleach or any other cleaning product.


As a Certified Indoor Air Quality Technician, I can tell you that bleach will in fact make mold worse. Bleach is very effective in removing the discoloration but leaves the microflora that will enable the mold to return in exactly the same spot when conditions are right. The most effective means of destroying molds, are biocides and anti-microbial solutions.


As far as your door is concerned, specifically:

  • Check the weather stripping and insure a good seal.
  • Check the serviceability of your HVAC system. Air Conditioners are also dehumidifiers.
  • Keep the doors clean of organic substances - mold can even grow on dirt.
  • Ask an IAQT to test the mold spores and determine the type of mold.
  • Clean the area with rubbing alcohol, or a solution with 60%-90% alcohol.
  • No biocides or anti-microbial solutions are EPA registered for use as a fungicide on wood substrates. – J Walters Jan 16 '16 at 18:45

Clorox and a hand pump tree soaker/sprayer. Then pressure wash. You will never 'win' with mother nature, but you can sack her behind the line of scrimmage and force a punt.

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