A Guide to Asbestos Testing for Home Inspectors and Homeowner FAQ

September 27, 2021 | 
asbestos testing

John was renovating his attic. He noticed old and spotted insulation, and he decided to replace it with newer, more energy-efficient insulating material. He ripped out the old insulation and installed the new material himself.

Seems harmless enough, right?

Unfortunately, John didn’t realize that the old insulation contained asbestos—and when he disturbed it, he unknowingly released dangerous asbestos fibers into the air. 

Chilling as this scenario is, it could have been prevented if John had hired a home inspector to perform asbestos testing before renovating. Testing for asbestos can give homeowners the knowledge they need to keep their homes in good repair without risking asbestos exposure and the health complications that come with it.

In this article, you’ll find everything you need to know about asbestos, how asbestos testing works, and how home inspectors can add asbestos testing to their arsenal of services.

What is asbestos?

Asbestos is a naturally occurring mineral that is soft, flexible, and heat-resistant. Because of its insulating and fire-proofing properties, asbestos has been used in many paper, cloth, cement, and plastic building materials for decades. 

Due to the danger it poses when inhaled, in 1980, builders began phasing asbestos out of use in home construction. But since more than half of homes in the United States were built before 1980, that means that more than half of U.S. homes likely contain asbestos in places like:

  • Vinyl floor tiles, vinyl sheet flooring, and floor tile adhesives
  • Cement, paper, and millboard insulation around woodburning stoves and furnaces
  • Furnace ducts insulated with an asbestos blanket or asbestos paper tape
  • Seals in stove gaskets
  • Wall and ceiling insulation
  • Textured paints, like popcorn ceilings
  • Cement roofing, siding, and shingles

Asbestos is very dangerous when it is disturbed. Damaging the material or removing it improperly during a renovation can release asbestos dust into the air. And once inhaled, asbestos dust becomes trapped in the lungs—and it can cause many serious and life-threatening health problems.

Health risks associated with asbestos

Once you breathe in asbestos, the fibers are trapped in your lungs. You may not notice any symptoms right away, but prolonged exposure to airborne asbestos can create lung tissue scarring and shortness of breath. 

Asbestos exposure can cause several long-term health effects, including asbestosis and mesothelioma. Asbestosis symptoms may not appear until one to four decades after the exposure, and they include:

  • A persistent, dry cough
  • Shortness of breath
  • Chest pain or tightness
  • Loss of appetite
  • Weight loss
  • Fingertips or toes appearing rounder and wider than usual (“clubbing”)

Asbestosis can increase your risk of developing lung cancer.

A malignant mesothelioma is an aggressive form of cancer that affects the thin tissue surrounding your internal organs, usually the lungs. This type of mesothelioma usually has the following symptoms:

  • Shortness of breath
  • Chest pain
  • Painful coughing
  • Weight loss
  • Lumps under the skin on your chest

While the potential health risks associated with asbestos are scary, the best way to avoid them is to have your home inspected for high levels of asbestos. With the knowledge that comes from a professional asbestos inspection, homeowners can protect themselves and their families by avoiding disturbing any asbestos products (or having them safely removed from the home).

How asbestos inspections work

If you suspect you have asbestos in your home, don’t touch it. Disturbing or damaging the material in question makes it more likely to release dangerous asbestos fibers into the air. Instead, call a professional home inspector to take a sample of the material for analysis. You should not attempt to take the sample yourself, since improper sampling procedures can release more asbestos dust into the air and be more dangerous than doing nothing.

Asbestos testing professionals will follow safety procedures when gathering samples, such as:

  1. Being the only person in the room
  2. Wearing gloves during sampling and washing hands immediately afterward
  3. Laying a plastic sheet on the floor below the sampling area
  4. Turning off the air conditioning or heating system to minimize airflow
  5. Disturbing as little of the material as possible while taking a sample

When they’re ready to begin, the home inspector performing the asbestos test will start by spraying water and detergent onto the surface of the material. Wetting the material makes it less likely to release dust.

Next, they’ll use a knife to cut a piece from the complete depth of the material. Moving precisely and slowly, they’ll place that sample into a tightly sealed container labeled with identification data for that test, including when and where the sample was taken. 

The clean-up process is just as important as the preparation process. The asbestos tester will clean any fallen debris from the sample area using a damp cloth or paper towel, and then dispose of it and the plastic sheet according to state and local asbestos disposal procedures. They’ll then use a small piece of duct tape to patch the sampled area so that dust won’t escape from the disturbed material.

After procuring the sample, the inspector performing the asbestos test will send it to an accredited asbestos analysis lab. The test results should indicate whether there is a presence of asbestos in the material, and if so, how much is present.

Environmental air quality tests

Some homeowners don’t need specific material in their home tested; instead, they just want to check on their indoor air quality to see if there is asbestos in the air. This testing is done by evacuating the area, using fans to keep air moving throughout the testing time (usually 8 hours), and setting up a collection filter to capture fibers in the air. 

There are two types of asbestos air quality tests:

Phase-contrast microscopy (PCM)

This method measures the total number of fibers in the air and doesn’t differentiate between asbestos and other types of fibers. The inspector collects the sample in the collection filter and holds it under a polarized light microscope to identify asbestos. If asbestos is present, the inspector counts the number of asbestos particles in the sample compared to the entire sample size. This should give a rough estimate of the asbestos concentration in the air.

PCM testing is less sensitive than other types of tests and can miss the smallest fibers, so this method is generally advisable only in situations when you already know asbestos is present and simply want to see how much is present. 

Transmission electron microscopy (TEM) 

This more sensitive method collects an air sample, which is sent to a lab to be tested. The lab uses electrons to highlight the presence of asbestos in the air sample. 

TEM is a more time-consuming and expensive process, but it is the best choice in situations where the homeowner wants to know whether asbestos is present in the air at all. 

Tips for home inspectors adding asbestos testing to their services

If you’re a home inspector, offering asbestos testing services alongside your standard home inspection is a great way to provide additional peace of mind to your clients. Asbestos testing is just one of many ancillary services you might add, along with air quality inspections, lead paint inspections, and radon testing.

But if you do decide to inspect for asbestos, be sure to do your homework and get the required training. Asbestos is a very dangerous substance that could pose a health risk to you as well as to your clients if handled inappropriately. 

Where to find training for asbestos inspections

The Environmental Protection Agency requires a certain level of training for asbestos professionals under the EPA Asbestos Model Accreditation Plan (MAP), which was issued under the Asbestos Hazard Emergency Response Act of 1986 (AHERA). In order to receive a certification, aspiring asbestos inspectors must:

  • Complete the required training
  • Pass an examination
  • Meet any other state requirements

Certified professionals must have initial training according to their state requirements, as well as annual refresher training. There are many refresher courses available online, but make sure your state approves the course before you take it.

If you would like to improve your home inspection business by becoming a certified asbestos tester, contact the appropriate agency in the state where you’ll be working to find approved courses in your area.The EPA offers a list of state requirements and approved courses by state that can help you begin your search.

Homeowner tips

If you’re a homeowner, you should be very careful of starting any renovation or repair project if your home was built before 1980 or if you have any other reason to suspect that asbestos may be present. 

If you live in an older home (or simply want to be cautious), consider hiring a home inspector to test for asbestos before drilling through drywall, replacing old insulation, removing vinyl floor tiles, scraping away popcorn ceilings, or cutting through pipe insulation. 

And you may also want to think twice before removing or repairing old household appliances like stoves, furnaces, dishwashers, and even automobiles.

Asbestos testing FAQ

Do you have to disclose asbestos when selling a house?

Unfortunately, federal law doesn’t require sellers to disclose the presence of asbestos to potential homebuyers. But your state may require asbestos disclosures, in which case, you would be able to sue the seller for failing to disclose. Check your state requirements to be sure.

And if the seller cut corners by DIY-ing a renovation without a permit, you may be able to sue them for doing unpermitted work.  

How can I test my home for asbestos?

There are asbestos test kits on the market that homeowners can use to collect samples and send to a lab for analysis. However, the safest way to know if you have asbestos in your home is to hire a professional home inspector to conduct a test for you. Improper collection methods can release asbestos dust into the air, putting you and your family at even greater danger. 

How much do asbestos inspections cost?

According to The Asbestos Institute, inspections generally range from $200 to $800, with the average cost being around $500. However, pricing can vary widely depending on the size of the building and the complexity of the test in question (for example, if air quality tests are performed, or multiple materials need to be sampled).


Whether we like it or not, asbestos is a hidden danger in many homes across the United States, especially those built pre-1980. The best way to guard against the severe health complications caused by asbestos exposure is to learn which materials contain asbestos—and then either dispose of them properly, or leave them undisturbed so that asbestos fibers don’t contaminate the air.

As a home inspector, you pride yourself in giving your clients the knowledge they need to feel safe in their homes. Adding asbestos testing to your list of services can give you one additional way to ensure your clients and their families can rest—and breathe—easy in the years to come.

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