
Mold in houses has received increased attention in recent years. When you look at the damage caused to both the physical health of humans and property this concern becomes clear.
Mold is a very common type of fungus consisting of microorganisms. Mold is found practically everywhere in small amounts and is generally harmless. When mold spores find moisture inside a house, they can start to grow. As these spores grow, they are released into the air where they can be inhaled. Depending on the person, the inhalation of these spores can cause serious problems.
What Are Mold Exposure Symptoms
For people that are sensitive to mold spores, symptoms can range from a stuffy nose, irritated throat, coughing, itchy eyes to more serious problems like lung disease or lung infections. For others that do not have this type of sensitivity, mold spores can have little or no effect.
There are certain types of mold spores that tend to flourish in moist indoor environments and create serious trouble for people who are sensitive to them. While there are over 200,000 different types of mold, we tend to see only a select few types that create problems in indoor environments.
The one we hear the most about is black mold or Stachybotrys Chartarum. This is a slow-growing mold that is not commonly found in nature. Health problems from exposure to this mold have been reported as early as the 1930s.

In a 1994 report from the Centers for Disease Control, several infants in Cleveland, Ohio area became sick and some died from pulmonary hemosiderosis (bleeding within the lungs) after exposure to high levels of Stachybotrys Chartarum spores. Additionally, Stachybotrys Chartarum or black mold has been linked to “Sick Building Syndrome”.
One of the most alarming aspects of black mold is that even dormant or dead spores still contain toxins. Think of a mold spore like a plant seed. When you buy those little packets of dried seeds at the store they are in a dormant state. Put the seeds in water and soil and they are no longer dormant and start to grow.
Mold spores are similar in that they can exist in a dormant state for long periods of time as well, mold spores in this state are called non-viable. The difference is that dormant mold spores still contain toxins which can be potentially dangerous to anyone susceptible to them.
If the conditions are right; moisture, warmth, and nourishment, non-viable spores can become viable or active and begin to grow and multiply, increasing in concentration and strength. This creates a more significant reaction to those susceptible and potentially affects more people.
Mold Can Damage Houses
In addition to the physical effects it has on people, mold can damage your home as well. Mold naturally decomposes organic matter like wood, sheetrock, etc…. Left unattended in a moist environment, mold can do some serious damage.
One common example we see is in homes that are built on a crawl space. It’s not uncommon for moisture to be found in a crawlspace which is a prime environment for black mold to flourish. Wooden floor joists can become wet, attracting mold. If left unattended these joists can begin to rot. Repair or replacement of these joists can be very expensive.

We generally see mold growing in homes as the result of some kind of water leak. In many cases, the leak is not obvious until the mold has become very established and it’s starting to cause damage to both people and property.
How to Find Mold in a House
The best time to discover you have a mold problem is before you actually live in the house. Home buyers should be very concerned about the existence of mold in any home they are considering purchasing.
The time to establish whether or not there is a mold problem is during the inspection phase of the Steps to Buying a House. While a general home inspector is most likely not going to be licensed to inspect and test for mold, they can look for evidence of its existence during the home inspection.
The inspector will be looking in the attic and inspecting underneath sinks as well as other areas that are susceptible to water infiltration. These are all areas where mold is most likely to grow and flourish.
If the home inspector does find signs of mold, their job is not to identify what types of mold spores are present but to locate the source that is creating the mold. This means leaking pipes, leaking roofs, etc…
Fixing a mold problem generally consists of two different parts, eliminating the cause and remediating the mold itself.
Mold remediation is certainly a valid inspection contingency. Kyle Hiscock over at the Rochester Real Estate Blog has a great article on the “Common Real Estate Contract Contingencies You Should Consider Including In Your Purchase Offer”. The article addresses not only mold but a lot of other important contingencies.
How to Test for Black Mold

There are a number of reasons to test for the existence of mold. The obvious one is to prevent or remediate human exposure to toxic mold spores. Testing can also help head off potential structural damage caused by mold.
If think you have a problem with mold the best plan of action is to have your home tested by a professional mold tester. These companies follow strict testing guidelines and protocols implemented by organizations like the American Industrial Hygiene Association (AIHA) and the American Conference of Governmental Industrial Hygienists (ACGIH). it’s important to note that even the EPA recommends using a professional testing entity.
A professional mold testing company will use three basic methods in their testing procedure.
DIY or home testing kits are less reliable and are frankly a waste of time because most likely, the home will need to be retested by a professional before any remediation begins. In most cases, professional testing is a requirement to provide documentation for insurance claims.
- Surface Samples – The surface sample test is useful when you can actually identify an area that appears the contain mold. This test is sometimes referred to as a tape test because the technician actually uses tape in order to collect the sample.
The subsequent surface sample is then tested to see if mold spores are growing on a surface and if so what type of spores are present.
- Air Samples– There are different types of devices used for air sampling but they generally work on the same premise. These devices use a calibrated air pump that pushes air past some type of collection point, usually a slide or petri dish. Any mold spores get left behind at the collection point. These slides or Petri dishes are sent to a laboratory for testing.
The advantage to air sample testing is that it can detect spores that are small and light enough to be carried along in the air we breathe.
Air Sample tests require sampling of the outdoor air be taken at the same session as the indoor air samples. This outdoor sample is used as a control for the sake of comparison. Since mold spores exist practically everywhere, the comparison looks for elevated levels of specific spores on the indoor sample compared to the outdoor sample.
- Dust Samples – This type of sample provides a historical record of what has been in the air. This type of test uses dust from both settled dust or carpet dust in order to determine if the air or surface samples are merely a snapshot of what is in the air or if the problems have been long term.
If you are Selling a Home Where Mold Grows Sharon Paxton, a REALTOR® from Newport Beach, has a great article explaining what you need to know.
How to Get Rid of Mold and Mold Remediation
If testing proves your home contains toxic mold the next step is remediation. It’s important to mention that you should not use the same company for remediation as you did for testing. This arrangement prevents any potential conflict of interest.
Mold remediation is also a task that should be done by a professional. These people have the equipment, protection, and knowledge to safely contain the spread and eliminate mold problems. Another aspect of mold remediation people overlook is the contamination of your belongings, things like clothes, bedding, and furniture. If these items contain toxic mold spores, they need to be cleaned up as well.
Trying to perform mold remediation as a homeowner not only exposes you to the toxic mold, but the potential for the mold to return is much higher. The CDC offers some good information on how to protect yourself during the cleanup or containment of moldy areas in your home.
The mold remediation process that most professionals use generally covers mold containment, mold removal, cleaning of contents and mold prevention. As with hiring any home repair work, it is wise to research the reputation of the remediation companies you are considering and obtain at least 3 bids for the work to be done.
Once the remediation is complete the professional will retest to make sure the indoor air quality is within acceptable limits.
If you are buying a house and discover mold as a part of your inspection. This is really something the home seller should remediate and repair as a part of your “Home Inspection Repair Requests”.
Will Homeowners Insurance Cover Mold Remediation?
Coverage for mold remediation from an insurance company really depends on how the mold occurred. Insurance companies will generally cover remediation if the source of the mold is related to something already covered by the policy, like water damage. For example, if the damage was caused by a severe storm and flooding or something like a burst water heater your homeowner’s insurance will most likely cover remediation.
On the other hand, if the mold has caused through your own negligence or lack of maintenance, the insurance company will most likely deny your claim.
Coverage is important because the cost of remediation can be very expensive. This is why it is essential to address any issues that could potentially lead to the development and growth of toxic molds.
Mold Problems for Home Buyers & Sellers

Mold is a serious concern for both home buyers and home sellers. Many home buyers will quickly walk away from a home purchase if there is a mention or suspicion of a mold problem. To protect home buyers, the Colorado Division of Real Estate state law requires REALTORS® to disclose toxic mold or any other adverse condition in a home. Unfortunately, even after professional remediation, some buyers will still not consider a home that has had a mold outbreak.
As a homeowner or the home seller, as part of the Home Selling Process, you should address mold problems as soon as they arise. Here are some helpful tips to head off a mold nightmare.
- Periodically inspect your home to detect any areas that may harbor a moist environment. Inspect your basement, crawl space and attic at least once a year to look for signs of leaking pipes or leaky areas of the roof and look for the presence of mold growth.
- If any leaks are detected, get them repaired immediately. While not all leaks produce mold, it is the top symptom of where a mold outbreak is likely to occur.
- If you see mold near the water leak or moist environment, stop working and contact a professional immediately.
- Hire a professional to do a mold inspection. This can be a costly endeavor, but it is often required in order to know how to remediate and control the situation.
- If mold is detected, hire a professional to perform remediation. Remediation usually first controls the existing mold, then prevents the mold from returning. Homeowner remediation is generally inadequate and often mold returns to the same area. Many reputable mold remediation companies offer a warranty for their work.
- Document the entire process and keep any and all receipts and reports from the professionals that you hire. If you are considering selling your home, documentation from professionals goes a long way to assure home buyers that the problem was handled in the proper way.
- If your home has had previous mold problems and you are considering selling, talk at length to your experienced Realtor. They should be aware of the proper disclosure forms and ramifications. If the situation or condition is particularly complicated, you should consult with an attorney that has experience in this area and in your home state’s laws. This could be costly but potentially could save you time and money in the long run on a problem property.
Red flags for potential mold sources start with things like water stains on walls, paint bubbling, sagging drywall or musty or moldy odors. Staying ahead of mold can save you financial pain down the road, it’s easier to fix small problems before they grow and spread creating a major remediation project.
Early awareness and quick action are the keys to avoiding health issues and costly cleanups of toxic mold.