How Long Does It Take For Black Mold To Grow & Spread

Do you have water damage in your home and are concerned about the presence of black mold?

Are you wondering if it’s already too late to prevent?

In this guide you will learn:

  • Factors affecting how fast black mold can grow & spread,
  • First Signs of Black mold & Most Common Causes Of Rapid Black Mold Growth,
  • How To Keep Black Mold From Growing After Water Damage.

How Long Does It Take For Black Mold To Grow After Water Damage

Can Black Mold Grow Overnight?

It doesn’t take long at all for black mold to begin to grow if the conditions are right- This can even happen overnight!

Black mold begins to grow as soon as its spores make contact with any damp material. This can be fabric such as a carpet, wood, drywall, paint, wooden or upholstered furniture, or anything else affected by moisture.

  • Within the very first day of its presence Black mold spores begin to spread and multiply, quickly affecting the air quality within your home.
  • Black Mold spores can spread throughout your entire house within 12 to 48 hours.
  • Within one to twelve days it can grow to cover an area of several square feet.

So as you can imagine, you don’t have much time to waste once water damage appears before black mold follows.

You may not be able to see the black mold initially but you can be assured it most likely has already started to form.

The scariest part is that the black mold in some cases may not be visible for up to 3 weeks, by which time it will be difficult to combat and the air quality in your home will be hazardous.

Once water damage has occurred in your home, contact your homeowners insurance as well as a water damage restoration company so you can address the situation before it becomes a nightmare.

First Signs That You Have Black Mold In Your Home

Stachybotrys chartarum, or as it is more commonly known, black mold, is one of the most common molds found indoors.

It grows in homes in damp and humid areas. Similarly to other molds, it releases mold spores into the surrounding air which can be inhaled by humans or absorbed through your skin.

The presence of mold spores in the air also makes for easy transportation from one area to another.

Some signs that you have black mold in your home include: 

1. Visible Water Damage Appearing As Dark Rings Or Spots

One of the very first signs that black mold is forming in your home is visible dark rings or spots that can appear on your walls and ceilings.

The spots may not be visibly moldy spots but they are an indicator of water damage, which is the primary cause of mold growth.

If you see pooled or collected water or excessive moisture in your home it’s best to clean the excess water and thoroughly disinfect the area with an antifungal to prevent black mold from forming.

2. Weird or Musty Seeming Smell

If you do not see visible black mold but you are noticing that a room or area in your home has an earthy, musty, smell, you may have black mold growing.

A professional inspector may be able to assist you in locating the source of the black mold if you can’t find it. It may be beneath paint or wallpaper, tile, or drywall.

In addition, if family or friends have commented on the smell in your home you may want to take this as a cue to have it checked out.

It is common for people to grow accustomed to the smell in their own home and be unable to discern if something is not right.

3. Breathing Irritation

The earliest symptoms of black mold exposure can be itchy skin and eyes, skin irritation, sneezing, coughing, and headaches.

If you are experiencing these symptoms and have had water damage in your home, you will need to have your home investigated and treated for black mold quickly before it has a chance to grow and spread.

4. Visibly Moldy Growth (Even If It’s Not Black)

You may be able to visibly see black mold infesting your home. Although it’s true that most black mold is visibly black in color, it can have a wide range of variations.

For example you may notice a dark, furry growth or what appears to be a black stain, or there could be white, orange, brown, and even green specks.

All of these can be toxic and dangerous to your health and home.

Factors Affecting How Long Does It Take For Black Mold To Spread

There are several factors affecting how long it takes for black mold to spread.

These Mainly are:

  • Amounts of Moisture in your home from water leaks or flooding,
  • How good is your Ventilation,
  • Indoor Temperature,
  • Poor Weather / Damp conditions outdoors

The Most Common Cause Of Rapid Black Mold Growth is unaddressed water damage.

You can take action to combat these factors.

Watch For Additional Leaks Or Damage

Be on the lookout for leaks around your appliances and ventilation ducts, as this moisture can accumulate and encourage growth.

Improve Airflow And Direct Damp Air Outside

If you don’t have access to a dehumidifier, make sure your home stays well-ventilated. This is important not just for preventing mold growth but also for removing spores from the air.

Reduce Humidity And Dampness

Mold thrives in humid, warm, damp conditions. Regularly check areas in your home that accumulate dampness, like in your bathroom or around heating and cooling systems. To take it a step further, invest in a dehumidifier to keep moisture levels in your home low.

Water Damage? Now Concerned about Black Mold?

Call 844-488-0570 for a Risk Free estimate from a Licensed Water Damage Restoration Specialist in your area.

We Can Help Fix the cause of the Water Damage, Dry out your house & Prevent Black mold from forming.

How To Keep Black Mold From Growing After Water Damage

There are several ways to keep black mold from spreading after water damage. These include:

  • Fix the Cause of the water Damage
  • Soak up & Remove all the moisture after water damage as fast as possible.
  • Clean With Disinfectants and Antifungals
  • Watch For Additional Leaks or Damage
  • Improve Airflow and Direct Damp Air Outside
  • Reduce Humidity and Dampness

Clean With Disinfectants and Antifungals

Note: When cleaning black mold affected areas, wear protective clothing over the whole body to avoid contact with toxic mold spores.

Gloves, goggles, and a dusk mask are recommended.

To clean the affected area, scrub with a scrub brush and soap and water. Throw away any cleaning supplies that came into contact with the mold affected area.

To clean you can use: Bleach, Hydrogen Peroxide, White Vinegar, Tea Trea Oil, and Grapefruit Seed Extract.

These can all be used to combat mold growth. These have antifungal and disinfecting properties that will create a less mold friendly environment where applied.

Hydrogen Peroxide: Spray on the area. Leave for 10-15 minutes and then rinse.

Grapefruit Seed Extract: Combine grapefruit seed extract with 2 cups of water. Spray on the black mold affected area and let dry.

Tea Tree Oil: Combine approximately 1 teaspoon with 1 cup water, spray on the affected area, and let dry.

White Vinegar: Spray undiluted white vinegar directly on the area and let dry.

Bleach is also a good disinfectant, but it is not recommended as it is a known irritant for the eyes, nose, and throat as well as any skin that it comes into contact with during use.

When To Call A Professional

When should you call a professional to address water damage to prevent black mold from forming in your home? When should you call a professional to address black mold that is already growing?

While everyone wants to save money on cleaning and repairs with DIY techniques, sometimes it is more beneficial to call in the professionals to avoid more stress and creating a bigger problem in the future.

Professionals can bring in specialized heavy duty equipment such as dehumidifiers and specialized vacuums to address water damage and excess water while purifying the air.

Their equipment, processs, and professional techniques allow them to have quicker drying times which means less time for mold to develop and spread.

Call a Professional if:

1.You have visible black mold that is spreading.

Visible black mold means the mold has likely already been forming for several weeks and made a significant base in your home from which to spread.

2. You recently had significant flooding, burst pipes, or leaking

Water damage is the primary cause of the formation of toxic black mold.

3. If you or anyone in your household suffers from symptoms or illnesses consistent with black mold toxicity or exposure, especially if you have children.

Studies have found that exposure to mold as a baby led to asthma as a young child. Black mold has even been linked to brain inflammation and neurological deterioration.

If your health is being compromised by the mold in your home it may be necessary to call in a professional to address it as they will have the proper protective equipment to remove any toxic or harmful debris while limiting the spread to other areas.

If you have symptoms of black mold related illness, check with your doctor or physician prior to attempting to remove the black mold on your own as this can be a significant hazard to your and your families health.

We have Water Damage & Mold Remediation Technicians that can help Fix the Water Damage , Deal with any Black Mold & Prevent it from Spreading.

For Disasters of all Sizes,available in 95% of the USA

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