How Fast Mold Grows After A Roof Leak

How Fast Mold Grows After A Roof Leak

Every homeowner has reason to worry about mold. Mold and mildew leave unpleasant smells, and some molds can be dangerous to folks with weakened systems. Just how fast does mold grow after a water leak? Why is mold in the home dangerous? What can be done to stop it? 


Mold spores are in every cubic foot of air. Most of these spores do not interact with us or cause any problems in our homes. Ample moisture and still air can combine to allow mold spores to settle and grow. 

Black mold, the kind that causes shudders and worries doctors, can take hold on a surface in around three days, spreading invisibly but quickly to all surrounding, moist surfaces. After 18 days of propagation, black mold becomes slightly visible on walls, floors, your attic, and on any moist, slightly porous surface. 

Left unchecked (or given additional moisture by well-intentioned amateurs), mold spreads quickly. For the first 10 to 12 days, the mold colony is establishing its foothold; after 12 days, it actively spreads and grows. Spraying a weak water-bleach solution, for example, will not kill off mold but will give it the moisture needed to grow. The area needs to be dried out as quickly as possible.

Black and green molds can be complicated to eradicate and are known to aggravate respiratory problems in family members with compromised health. Asthma, allergies, congestion, watery eyes, sinus headaches, and other ills can beset anyone sensitive to black and green molds. 


Solving mold in your home may require a call to a mold remediation company. Preventing mold begins with active measures you, as the homeowner, can take in partnership with your local roofer:

  • If you find mold and mildew, dry the area out completely before doing anything to remove the mold and mildew.
  • Protect your home by having roof leaks repaired promptly by a trustworthy, professional roofer.
  • Monitor areas with mold or dampness for at least three weeks after the incident.
  • Consider dealing with the reasons your roof leaks; a substantial metal roof can solve a lot of your mold issues, helping to improve the health of your family and your bank account.

If you are a homeowner in the Iron Range or Phoenix and Tucson metropolitan areas, please contact us today or get a free metal roofing quote to learn more about metal roofing, roof leaks, and the problems mold can cause. Vertex Metal Roofing is your total solution to your concerns about mold, mildew, and water infiltration.

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