Mold inspection and testing is a big business. Every year, thousands of mold testing and inspection companies put out marketing information instructing home and business owners that mold testing is necessary and to get their properties regularly inspected, just in case they have a mold problem.

Savvy property owners, however, may wonder whether mold testing is worthwhile. Does it make sense to test the mold before removing it?

The answer to that question, much to the horror of most mold removal companies, is probably not.

When mold is present at the microscopic level, it’s not usually a matter of concern. Mold spores are a natural constituent of the atmosphere and how the species propagates. They’re a part of the natural environment, and in the air we breathe both outside and in our homes. It’s only when mold grows to the size that we can see it that it becomes a problem.

Most mold inspections are usually a waste of time and money, although mold inspection companies will never tell you this. It turns out that once you can see mold, there isn’t anything else you need to do other than remove it. It’s that simple.

Most mold testing companies will charge people in the region of $300 to $1,000 to check for mold – a substantial sum of money that probably isn’t necessary. If you can’t see mold, then it’s not likely to be a problem. If you can see it, then it needs to be removed.

Why Only Visible Mold Is A Problem

You might think that it’s worth finding out what kind of mold is in their environment to determine whether it’s toxic or not. Concerned homeowners call out mold testing professionals to identify the precise species of mold in their home. The firm then cross-checks the results with their database of mold species and provides a report on the dangers it poses.

Granted, not all molds are dangerous to everyone’s health. The health related risks with mold can be subjective to an individuals personal allergy symptoms and other health issues. There are more than 100,000 species so far identified by modern science. Only a subset of them have been proven that create chemicals which can be harmful to individuals that otherwise don’t have hypersensitivities. But this fact is beside the point and underscores why testing for mold is a waste of time and money. If you have visible mold in your home, your priority should be to remove it, because it’s likely to be detrimental to your health and the overall value and pleasantness of your home.

What about testing for mold when you can’t see it?

It might seem like testing for mold when none is visible is a good policy. Tiny quantities of mold in your home could still be causing damage to your health, right?

Unfortunately, it’s not as simple as this. As discussed above, mold is a natural part of the environment, and our bodies are mostly designed to cope with spores in small quantities. If mold is not visible to the naked eye, then it’s unlikely to be pumping out sufficient numbers of spores to damage either your health or your home. However if you or are experiencing health related issues, have ruled out other causes for the symptoms you are experiencing, and it was advised by a medical professional to be a cause of your symptoms, then we would strongly suggest to make the investment of testing your home.

By contrast, if mold is visible, then it probably is churning out sufficient nasties to make it worth cleaning up. Again, there’s usually no need to perform a mold test: you’ll want to remove the mold in any case.

What Does The EPA Say About Mold Testing?

It might be hard to swallow the idea that mold testing is, in most cases, superfluous, but the EPA supports the concept. It argues that when visible mold growth is present, sampling is “unnecessary” – the mold should just be removed. It then goes into detail about the circumstances in which you might want to use a conduct mold testing, but these are few (we’ll discuss them below).

One of the reasons that the EPA doesn’t recommend mold sampling, in general, is that there are currently no officially recognized guidelines for acceptable mold levels in the home. Nobody has yet done the science to determine the level of mold exposure which an average person can tolerate without suffering any adverse health consequences.

The fact that there are no guidelines is interesting. It suggests that there is a lack of proper research in the area and that the real consequences of mold on health are difficult to quantify. Small scale studies indicate that it can lead to respiratory difficulties and “sick building syndrome,” but we don’t yet know the concentration of mold required, nor the most harmful species.

“Black mold” is often held up as a particularly pernicious form of mold. You often see mold that’s black in color on bathroom caulking or window frames. But is black mold as harmful as many people in the mold testing industry claim?

The truth is that many of the 100,000 species of mold are black, and many of them are entirely harmless. Just because mold is black doesn’t mean that it will lead to allergies or worsening asthma. Likewise, mold that isn’t black isn’t necessarily harmless either. Some non-black molds are highly detrimental to health. A black mold test is just a regular mold test as applied to species which present as black.

When Should You Inspect Or Test Mold?

Okay, so we’ve discovered that conducting a mold inspection usually isn’t necessary. But there are any circumstances in which it’s a good idea?

When You Can Smell Mold But Can’t See It

You might not be able to see mold, but if you can smell it, then that would suggest that it’s present in your home in sufficiently high quantities for concern. Mold, for instance, can buildup in the interior of drywall, because damp drywall offers both moisture and a source of food from the organic paper backing. Mold assessments help to identify whether there is, in fact, mold in your environment, and help you detect areas closest to the source.

Your Insurance Company Requires It

Sometimes insurance carrier’s need to justify objectively the existence of something in order to pay for it. It is like having to see your general doctor to get a prescription to see a specialist in order for the insurance company to pay for it. It will seem like an unnecessary waste of time and money, but very necessary if you want to be compensated for your property damages.

You’re Interested In The Air Quality Of Your Home

If you’re selling your home or renting it out, then the buyer or tenants might be interested in the internal air quality. A mold test is an essential part of that testing process, informing new owners or renters before they move in.

You Need To Perform An Air Quality Test To Protect Buyers And Sellers

Buyers and sellers want to know whether air quality in their homes meets standards set out in the sale contract. If quality is low, it could lead to a claim by the buyer that the seller did not adequately inform them about air quality in the home.

You Have Specific Health Concerns

Sometimes a patient might be suffering from headaches, constant sneezing, or coughing indoors without an obvious cause. Because people differ in their sensitivity to mold, a doctor might recommend a home mold test to rule out mold spores as a possible source of irritation, even if mold is not visible.

You’ve Got Plumbing Issues

If you’ve known about plumbing issues in your home for a while, there’s a good chance that you might have a mold problem in your home, even if you can’t see it. A mold test can rule out mold issues and help you resolve any that may be lurking out of sight.

You Had Mold In The Past And Want To Check That It Hasn’t Come Back

If you had mold in the past, either because of high humidity or a leak in your home somewhere and then had it removed, it’s often a good idea to check whether it’s stayed away or come back. Checking tells you whether you’ve genuinely resolved the underlying issue or not.

Why You Shouldn’t Buy An Over-The-Counter Mold Test Kit

With the growing perception of problems associated with mold, more and more people are looking into how to test for mold at home. Over-the-counter mold test kits are becoming increasingly popular, thanks to their convenience and apparent value-for-money. Unfortunately, many of these products are, for want of a better word, a rip-off.

Problems with interpreting results. Interpreting the results of mold test kits isn’t as simple as you might think. Over-the-counter product manufacturers want you to believe that anybody can understand what their tests say, but it’s often not as simple as that. Ideally, you want a professional to interpret the results for you.

Professionals should conduct sampling. The fact that professionals should only do sampling isn’t just the biased opinion of those in the mold testing profession; it’s the conclusion of the US Government. The EPA says that only professionals should carry out mold testing. Only professionals have the requisite experience and knowledge to design and implement mold sampling professionally. Amateurs are much more likely to generate false positives and negatives.

Mold test kits are useless when you can’t see the mold. One of the biggest reasons for testing for mold is when you can’t see it but think you can smell it. Over-the-counter mold test kits, however, require you to have visible mold in your environment – they can’t tell you whether that annoying moldy smell is, in fact, mold.

You’re almost certain to detect mold with a mold test kit whether it’s a problem or not. The atmosphere contains millions of mold spores, all looking for potential sites to inhabit and grow. The chances are, therefore, that mold will start growing on a test kit petri dish, whether or not it’s a real problem in your home. You may wrongly conclude that you have a mold problem when you don’t.

Home kits don’t tell you anything about what caused the mold outbreak in the first place. One of the jobs of a mold inspection professional is to perform a visual inspection of the mold to determine what might be causing it. Mold can grow for all kinds of reasons, from leaky plumbing to a lack of extraction vents to cracks in your drywall. A home test kit might tell you that you have mold in your home, but it won’t tell you why. It could be natural variation. It could be problems with your foundations; it could be issues related to your guttering: you just don’t know.


If you suspect mold problems in your home, there’s usually no need to conduct a mold assessment or have a mold inspection. As soon as mold is visible, it’s time to call in the removal specialists, instead of worrying whether it’s a toxic variety or not. Mold removal specialists can get rid of the mold and make recommendations for dealing with the source of the problem. Professionals wholly remove the mold problem and have the equipment to do so safely.