How to Test for Mold in Your Home

Thinking that you have found mold in your home can be scary, as you may worry that it will make you and your family sick. Not knowing exactly what you’re seeing–or if the mold is hiding behind a wall–could cause undue stress. Rather than spend your time worrying, use this guide to learn how to test for mold in your home, and take the necessary steps to remove it. 

Indicators of Mold

You don’t want to spend time and money on learning how to test for mold in your home if there’s no reason. Instead, look for a few indicators that you may have mold before you choose to test or schedule an inspection.

Visible Signs of Mold

Seeing mold on your walls or ceilings is the most obvious indication that you have a problem with mold. It often looks like dark, fuzzy spots that can resemble a stain. Some molds have white or orange flecks on the dark surface. However, mold can be almost any color or texture. 

Mold often has a damp, musty smell as well. If you see something that you think looks like mold, and it has this odor, it’s time to test. If you notice this odor in areas where you cannot see any mold, you could have mold growth inside your walls.

Reactions Similar to Allergies

If you and your family members are struggling with breathing problems, nasal congestion, a sore throat, itchy eyes, or similar symptoms that don’t seem to have an explanation, a high number of mold spores may be present. During an initial exposure to mold spores in the air, many people may feel like they are having an allergic reaction.

Through prolonged exposure, you may notice stronger symptoms. You could end up with a respiratory infection that leaves you with a fever or coughing up blood. Don’t wait for these serious symptoms to appear. Figure out how to test for mold when you notice unexplained allergy symptoms.

Known Areas of Moisture Problems

Mold needs significant moisture to begin to grow. If you have areas where moisture persists for whatever reason, testing for mold is a good idea. Some moisture problems can occur in instances like:

• Flooding from rain

• Broken water pipe

• Leaky roof

• Condensation on water pipes

• Condensation on HVAC ductwork

• Seeping concrete foundation

• Bathrooms without exhaust fans

• Near indoor dryer vents

• Leaky bathtub or shower

Testing Mold Safely

If you decide to test for mold on your own, rather than hiring a pro, you need to do so safely. 

Wear Protective Gear

If you will be working around mold or inspecting it up close, always wear safety goggles, gloves, and an N-95 respirator. The respirator should cover the nose and mouth. You should be able to find this gear at a local hardware store.

Cover Exposed Skin

Don’t leave the skin on your arms, legs, or neck exposed. Consider using a full-sized coverage suit or a coverall that protects your clothing and skin. The full coverage suit may have a hood and protection for your shoes, too.

Minimize Disturbance of the Mold

Even when wearing safety gear, you should try to avoid pulling the mold loose or jostling it. Each time you make contact with the mold, you could release its spores into the air, where they could spread to other areas of your home. Conduct your test as carefully as possible.

Three Ways to Test for Mold

After donning your safety gear, you can test for mold in your house in one of three ways: 

Use a Cotton Swab and Bleach

For a DIY testing method on a growth area that you can see, mix one part of bleach to 16 parts of water in a bowl or small bucket. Dip a cotton swab into the mixture and touch the area that you think is mold. If the area is mold instead of grime or dirt, it should lighten in color immediately.

Buy an At-Home Testing Kit

Most home improvement or hardware stores will have mold testing kits that you can purchase for between $10 and $50. The kit often includes a swab or a scraper for collecting some of the growth that you think is mold. The kit may tell you that mold has been detected, or you may have to send the sample to a lab. Again, this test only works if you can see spots that you believe are mold growth.

If you want to test the air in your home for elevated mold spores, you can find an air quality test at the home improvement or hardware store, as well. You will most likely have to send this sample into a lab for testing.

Hire a Professional Mold Inspector

The third option involves relying on a pro to do the inspection for you. The inspector visits your home and runs a number of tests. The cost of a mold inspection from a pro averages around $600. If you have a large amount of square footage to inspect, you could pay up to $1,000.

Common Trouble Spots for Mold Growth

According to data from Angi customers, most homeowners (38.2%) suspect they have mold on their walls and ceiling, and 19.5% suspect they have mold in their HVAC system. If you’ve ever had leaks in your roof or other areas of your home, the likelihood of mold growth increases. If you have a suspicion that there’s mold anywhere in your home, the safest way to handle it is to call a professional for mold testing.

What Happens in a Mold Inspection From a Pro?

When you hire a pro to do a mold inspection, the pro will search for visible signs of mold growth throughout your home. Additionally, they may look for signs of excess moisture that could lead to mold formation.

The mold inspector may take air readings as well, looking for a higher number of mold spores in the air than expected. It can take anywhere from 2 to 6 hours to complete the inspection. 

If signs of mold do exist, the inspector may take samples for testing. Results should be back in 1 to 2 business days in most instances. Should the inspector determine you have a mold problem that needs remediation, they may give you a list of options and a checklist to follow to keep you and your family safe.

Should I Get a Mold Inspection?

Professional inspections are costly, so you may be wondering—do I need a mold inspection? If you see active mold growing, you should call a mold inspector as soon as possible. 

However, if you are unsure if you are seeing mold, or smelling mustiness related to mold inside the walls, you may want to test for mold in your house first. If your test shows you may have a mold problem, you should contact a local mold inspection professional for a thorough mold inspection. 

Don’t put a test or inspection off. The earlier you catch a potential mold problem, the easier—and often cheaper—it is to solve. 

What to Do if a Mold Test is Positive

If you have a positive mold test, it’s important to reach out to a mold remediation expert as quickly as possible. Mold can spread quickly over several days and weeks, so you do not want to wait to treat the problem. Waiting could drive up the cost to fix the problem, and increase the risk of illness for your family.

For help with hiring a mold remediation company, you can seek recommendations from family, friends and trusted resources for finding a local mold remediation pro. The pro you hire may also have recommendations for a remediation company you can use to kill mold in your home.

Until the pro is able to remove the mold, avoid disturbing it. Don’t cover it or try to clean it, as this will likely cause more mold sports to enter the air inside your home. The remediation company may have recommendations for you to follow, too.

How Mold Impacts Your Health

People will have different health reactions to the presence of mold. Some people react severely, while other people may have no symptoms. Some of the most common reactions to mold exposure include:

• Difficulty breathing

• Irritated throat and nasal passages

• Increased congestion

• Coughing and wheezing

• Eye irritation and itchiness

• Skin rash

• Fever

• Lung infections

People with compromised breathing due to asthma, lung disease, or a weakened immune system are more likely to have a severe reaction to mold exposure.

Mold exposure usually results in short-term health issues. As long as you remove the mold from the home, your health should return to normal. However, children and elderly people could have lingering symptoms.

Because any type of mold could negatively impact your health, it’s best to take steps to prevent mold and avoid exposure. Call a pro who inspects for mold and can do the proper tests. If you have mold, hire a local mold removal pro to remove it and prevent it from coming back.

Where Does Mold Commonly Grow?

Mold is most likely to grow in places with constant dampness and a lack of ventilation. Dampness can come from leaky pipes inside walls, moisture seeping through a basement foundation, flooding, leaking roofs, and similar issues.

Some of the most common areas where you could find mold include:

• Basements

• Attics

• Bathrooms

• Near windows and doors

• Under leaky appliances

• Near leaky plumbing pipes

• Near a floor drain

• Under wet carpet or insulation

• Near wet cardboard storage boxes

• Near air conditioning condensate drain lines

• Under leaky roofs

If your home has high humidity, mold could grow anywhere. Techniques to lower the humidity in your home may include using a dehumidifier, operating fans, and running your air conditioner more often.

How Much Does Mold Remediation Cost?

The final mold remediation cost will depend on the extent of the mold infestation. An average cost is about $2,200, but you could pay significantly more or less. If the mold is inside your walls, for example, removing it will be more challenging, which will increase the price you pay. If it’s a small patch, located on easily-accessible drywall, the cost could be less than average.

You may have additional costs to replace items that suffered mold damage, such as drywall on the ceiling or walls.