Most people are well aware that mold growth in the home is a dangerous condition that can easily result in extensive structural damage and various health hazards. It is also well known that the only way to prevent such troubles is to take quick and efficient measures at the first signs of a mold problem in the house.

What the majority of people don’t know, however, is how to determine the extent of the damage and decide whether professional help is necessary or not. In some cases – when the contaminated area is small and the affected materials are easy to clean – the homeowner may be able to take care of the problem on their own. In others, professional mold removal and remediation is the only viable option.

If you’re dealing with mold contamination in your home, you may not be sure how severe the problem is and what cleanup and remediation measures to take. The comprehensive guide below will help you understand the difference between the various levels of mold damage and decide on the best course of action in each particular case.

Mold Levels in House

The different stages of mold damage are usually divided into five levels. Level one is the level with the least contamination and level four is the one with the greatest degree of contamination. Level five refers to mold growth in the HVAC system.

Mold Damage Level 1: 10 Square Feet or Less

When the contaminated area is restricted to under 10 sq. ft., the mold problem is unlikely to be caused by structural or HVAC issues. It is categorized as level 1 and is fairly easy to fix. The mold spores are usually found on ceiling tiles, baseboards, and/or wall panels exposed to high humidity or temperature fluctuations. The mold can be easily removed and the affected surfaces – effectively cleaned without professional help.

All you need to do if you find mold contamination at level 1 in your home is run a wire brush over the moldy surfaces (immediately followed by disposable wipes), then clean the area with a cloth dipped in a detergent solution. Alternatively, you can spray the surfaces with vinegar or use a fungicide spray. Dry the cleaned surfaces thoroughly and keep the area well ventilated. This simple mold removal technique works well for wood surfaces and non-porous materials, such as tile, glass, and metal.

There are, however, a few important precautionary steps to take:

• Do not attempt DIY mold cleanup if you suffer from asthma or immune disorders, or if you have allergies;
• Wear personal protection gear – rubber gloves, goggles, and a disposable respirator;
• Keep children, elderly people, and people with chronic lung diseases or compromised immune systems away from the work area;
• Clean any affected items and household surfaces with uttermost care. Use appropriate cleaning products and make sure the items are fully dry before putting them back to use;
• Dispose of contaminated items and materials that cannot be properly cleaned (porous materials, such as carpeting and ceiling tiles) in sealed plastic bags to prevent the mold spores from spreading to other parts of the home;
• Ensure proper ventilation and wait until the area is completely dry before resuming any activities in it.

Mold Damage Level 2: 10 to 30 Square Feet

Level 2 mold damage refers to contaminated areas of 10 to 30 sq. ft. The larger amount of mold may be indicating an underlying problem in the plumbing or air conditioning systems, but this is not always the case.  If entire wallboard panels are contaminated, however, a careful inspection of the building is strongly recommended.
If you’re dealing with level 2 mold damage in your home, you have a good chance to fix the problem on your own. Just don’t forget to take all the precautions described above and make sure you:

• Find the source of the excessive moisture and take the necessary measures to prevent mold growth in the future;
• Cover any unsalvageable moldy materials with plastic sheets and seal them tightly with tape before taking them out of your home. This will help contain dust and debris and will prevent mold infestation in other parts of the house;
• When you’re done, vacuum the entire work area with a vacuum cleaner equipped with a HEPA filter, then wipe down all hard surfaces with a cloth or a mop dipped in a detergent solution.

Mold levels one and two are not considered to be dangerous. They do not pose a serious threat to the health of the residents or the structural integrity of the building. Even though level 2 warrants a deeper look and may quickly turn into level 3, both of the first two levels are manageable without professional help – areas of mold contamination smaller than 30 sq. ft. do not require expert mold inspection, testing, and remediation services.

Mold Damage Level 3: 30 to 100 Square Feet

Large areas of mold growth (more than 30 sq. ft.) indicate a significant problem that requires immediate action. If several wallboard panels, ceiling tiles, or other large surfaces are contaminated, the remediation efforts must start as soon as possible. The first step is to have the building professionally tested for mold (mold inspection will help define the extent of the damage and the scope of the required mold cleanup). Then, it is advisable to consult an experienced mold specialist about the best course of action.

If you have level 3 mold damage in your home, you should seriously consider hiring a professional remediation company to take care of the problem. If you prefer to attempt DIY mold removal, you need to take the same precautionary measures as for level two mold contamination and:

• Make sure you seal all the areas of the home adjacent to the infected area with plastic sheeting;
• Tape plastic sheeting over any ventilation grills and air ducts in the work area to prevent contaminating the HVAC system;
• Do not allow anyone into the infected area until the work is completed. Keep young children, seniors, people with chronic lung diseases, individuals recovering from recent surgery, and anyone with a suppressed immune system away not only from the contaminated area, but also from all other directly adjacent areas of the home.

Mold Damage Level 4: 100 Square Feet or More

Level 4 contamination (over 100 sq. ft.) poses serious health and safety risks and requires professional remediation. Everyone working on the mold removal task must be trained in handling hazardous materials and has to wear face respirators with HEPA cartridges and disposable protective clothing. The mold remediation experts will:

• Isolate the contaminated area from the rest of the home with sealed plastic sheeting over doorways, air ducts, and other openings;
• Perform all the necessary mold removal and remediation procedures, as well as any required or desirable repairs;
• Thoroughly clean the area and restore any salvageable items and household surfaces to an excellent condition;
• Set up a decontamination chamber to remove disposable clothing after the work is completed and sanitize the outside of sealed bags containing contaminated materials before taking them away from the property;
• Use air filtration machines with HEPA filters to purify the air and monitor indoor air quality to determine when it is safe for the residents to move back in.

Level 4 mold remediation is a laborious and time-consuming process that should not be left in the hands of inexperienced people. Make sure you hire highly qualified, properly licensed, and fully reliable mold remediation specialists to take care of the mold problem in your home.

Good to remember: Once your home is free of mold, take every possible measure to prevent its growth in the future and avoid similar troubles.

Mold Damage Level 5: HVAC System Contamination

All remediation procedures for air conditioning units and HVAC systems should be left to the professionals. The following precautions should be taken during the remediation work (in addition to the safety measures for all previous levels):

• The HVAC system must be shut down;
• Contaminated insulation must be removed and sealed in plastic bags, then properly disposed of;
• Biocide products (specialized antimicrobial agents) should be used with HVAC components, such as cooling coils and condensation pans, to kill inaccessible mold spores inside the ductwork and prevent mold growth in the future.

Good to remember: Any mold growth in your HVAC system should be removed by a professional, no matter how large or small the area is.

How to Check Mold Levels in House

The earlier you become aware of a mold problem in your home, the easier it will be to take care of it. Therefore, it’s very important to learn how to detect mold in its earliest stages and how to test mold levels in your home, so that you know what measures to take in order to get rid of the harmful microorganisms and prevent further troubles.

Step 1. Watch out for the first signs of mold growth in your home – musty smell, cracked or blistering paint, bulging of the walls, cracked or loose tiles, a softer, spongy feel of the floor or walls, inexplicable allergic reactions among members of your household, etc.

Step 2. Check for visible mold – inspect the areas in your home where mold is most likely to grow – the basement, shower curtains, ceiling corners, around windows, under sinks, any places recently exposed to excessive water, etc.

Step 3. Collect mold samples – use a mold test kit (in-home testing kits come with appropriate instruments and detailed instructions) to:

• take samples of the air in your home to identify the concentration of mold spores in your indoor environment; or
• take samples from different household surfaces to find the amount of mold growth on household materials.

Then, submit the sampling to a local mold testing laboratory for examination and analysis. Keep in mind, though, that the results are not very reliable because the amount of mold spores in the air can change drastically in a small amount of time and mold growth isn’t spread evenly across all surfaces in the home.

Step 4. Have your home professionally tested for mold – if you suspect a more serious mold problem, you’re advised to hire a professional mold inspector to test your home. The experts have specialized equipment and extensive experience in collecting and analyzing mold samples which guarantees that the results will be full and accurate – you will know the exact amount of mold spores (living, dormant, and dead) in your living space, as well as what species of mold are present in your home. Then, you’ll be able to determine what measures will be required to get rid of the mold and restore the safe and healthy living conditions in your home.

Mold testing will not only tell you if you have a mold problem in your house, but will also help you identify the extent of the damage (the mold level) and decide whether you can cope on your own or need professional mold removal and remediation services.