Five-Star Reviews Don’t Always Mean Five-Star Remediation

When choosing a mold remediation company, homeowners often rely on five-star reviews. But what are those reviews really telling you?

Most reviews reflect whether the workers were friendly, courteous, punctual, respectful, and cleaned up after themselves. Those are all good qualities, but they don’t necessarily tell you whether the mold was properly removed.

A company can have hundreds of five-star reviews and still perform inadequate mold remediation.

Most homeowners aren’t trained to recognize improper remediation practices. Fortunately, there are warning signs you can watch for, both during and after the work.

And here’s something important to remember: If something doesn’t look right, smell right, or make sense to you, question it. Don’t assume the contractor knows best simply because they’re the professional.

Warning Signs During Mold Remediation

1. Gaps or openings in plastic containment

The plastic barriers surrounding the work area are intended to prevent contaminated dust and mold spores from spreading throughout your home. Tears, loose tape, openings, or workers repeatedly lifting the plastic to enter and exit can compromise containment. The work area should also be maintained under appropriate negative air pressure.

2. Workers walking through your home in contaminated clothing

Workers should follow proper decontamination procedures when leaving the work area. Walking through your living spaces wearing contaminated protective clothing, gloves, or footwear can spread mold spores and dust into previously unaffected areas.

3. Dirty equipment brought into your home

Air scrubbers, HEPA vacuums, hoses, and other equipment should be clean and properly maintained. Equipment covered in dust or debris from previous jobs raises concerns about cross-contamination.

4. Musty or unpleasant odors escaping containment

If you suddenly notice musty odors or demolition-related smells in other parts of your home, speak up. This could indicate that contaminated air is escaping the work area. Don’t accept the explanation that it’s simply part of the process without asking how containment is being maintained.

5. Heating or cooling systems operating during demolition

Supply and return vents within the work area should be properly sealed or isolated. Allowing contaminated dust to enter the HVAC system can distribute it throughout the building. The system serving the affected area should generally be shut down or appropriately isolated during dusty demolition.

6. Contaminated debris carried through living spaces

Mold-contaminated drywall, insulation, and other materials should be securely bagged or wrapped before leaving containment. Workers should not carry loose contaminated debris through your home.

Warning Signs After Mold Remediation

7. Visible dust or debris left behind

After remediation, the work area should be thoroughly cleaned. Dust, drywall particles, sawdust, insulation fragments, or debris remaining on framing, floors, or other surfaces suggest incomplete cleaning.

8. Dark staining or suspected mold remaining on wood

Not all dark staining is mold, and some discoloration can remain after successful cleaning. However, suspicious areas should be evaluated rather than ignored, painted over, or covered with new drywall.

9. Remaining water damage or fiberglass insulation

Bubbling paint, warped baseboards, deteriorated drywall, and other signs of moisture damage should be investigated. Wet or contaminated fiberglass insulation should not be left inside wall cavities. The original moisture problem must also be corrected, or mold may return.

10. Air scrubbers running for days without filter maintenance

Air scrubbers are often left running for 24–48 hours after cleaning. However, heavily loaded pre-filters should be inspected and changed as needed, and HEPA filters should be maintained according to the manufacturer’s requirements. Ask whether the filters have been evaluated before the equipment continues operating.

11. The contractor wants to close the walls immediately

Once new drywall and insulation are installed, it becomes much harder to determine whether the remediation was successful. Independent post-remediation verification should ideally take place before reconstruction, while the affected areas are still accessible.

Five Questions to Ask Your Mold Remediation Contractor

Before work begins, ask these five questions:

1. How will you prevent mold spores and contaminated dust from spreading into the rest of my home? Ask about containment, negative air pressure, and worker decontamination.
2. How do you clean and maintain your equipment between jobs? This includes HEPA vacuums, air scrubbers, hoses, and filters.
3. How will you protect my heating and cooling system? Ask whether vents will be sealed and whether the system will be shut down or isolated during demolition.
4. How will you determine that all affected materials have been properly addressed? Ask about hidden mold, contaminated insulation, moisture measurements, and cleaning exposed framing.
5. Will you allow independent post-remediation verification before removing containment and rebuilding? A reputable contractor should be willing to have the work independently evaluated against agreed-upon clearance criteria and return to do additional cleaning if the remediation verification fails.

Trust Your Observations. You Have Every Right to Ask Questions.

This may be the most important advice in this article.

You do not need to be a mold expert to recognize that something may be wrong. 

If you see a hole in the plastic containment, ask about it. If workers are walking through your home in dirty protective clothing, question it. If you smell musty odors in rooms that previously smelled fine, say something.

Don’t dismiss your concerns because someone tells you, “We’ve been doing this for 20 years,” or “This is how we always do it.”

Experience is valuable, but it doesn’t excuse improper procedures.

A professional contractor should welcome reasonable questions, explain their procedures, and correct problems when they are identified.

Your home is not the place to remain silent because you’re afraid of questioning a professional.

The Best Way to Know Whether Remediation Was Successful

The appearance of a clean room doesn’t necessarily mean the environment is clean.

Independent post-remediation verification can help determine whether contaminated materials were adequately addressed, moisture conditions are acceptable, and the work area meets appropriate clearance criteria.

Whenever possible, this assessment should be performed before containment is removed and before walls or ceilings are closed.

Remember: A five-star review measures customer satisfaction. Independent verification evaluates the quality of the remediation. They are not the same thing.

Indoor Environmental Testing, Inc. provides independent environmental assessments and post-remediation verification to help homeowners make informed decisions about their indoor environments.

We detect what you suspect.

Have you ever noticed a musty smell in a basement—or even in your own home—while someone standing right next to you says, “I don’t smell anything”?

There may be a scientific reason for that.

Research has consistently found that women, on average, perform better than men at detecting, identifying, and distinguishing odors. A large meta-analysis published in Frontiers in Psychology confirmed this female advantage across several different measures of the sense of smell.

Why? Researchers believe there are several factors involved, including differences in the brain and the influence of sex hormones. Estrogen and testosterone both interact with the olfactory system. Some research has suggested that testosterone may decrease sensitivity to certain odors, although the relationship between hormones and smell is complicated and scientists have not established that testosterone universally suppresses the sense of smell.

We have an interesting real-world example of this from our own field.

One experienced female mold inspector had an exceptionally keen sense of smell. In fact, her nose was a valuable tool during mold inspections. She could often detect a musty or unusual odor immediately upon entering an area.

Later, she was prescribed testosterone therapy because of muscle loss. After beginning testosterone, she noticed something remarkable: her sense of smell had drastically diminished.

That is only one person’s experience, so we certainly can’t say that testosterone was proven to be the cause. But it is an interesting anecdotal observation considering what researchers have discovered about the relationship between reproductive hormones and our sense of smell.

But Sometimes It Isn’t About Whether You Smell It

There’s another fascinating part of this that we’ve noticed after years of investigating homes: two people may actually smell the same thing but interpret it differently.

During one basement inspection, a husband told us that he couldn’t smell mold. His wife, however, clearly could.

So instead of asking him again whether he smelled mold, I asked him a different question:

“Do you smell wet dirt down here?”

“Yes,” he replied.

That changed the conversation. He was detecting an odor. He simply wasn’t identifying it as a mold or musty odor.

Over the years, we’ve heard men describe odors in mold-affected environments as dirt, wet wood, earthy, damp, or an old-basement smell, while women may describe a similar odor as musty or moldy. That’s our observation from the field—not a scientifically established rule about men and women—but it demonstrates something important.

Our sense of smell isn’t just about what reaches our nose. The brain also has to recognize the odor, associate it with previous experiences, and decide what to call it.

That’s why, during an environmental investigation, asking someone “Do you smell mold?” may not be the best question.

Sometimes a better question is simply:

“What does it smell like to you?”

The answer may tell us much more.

So, if one person in your family keeps saying that something smells musty and everyone else thinks they’re imagining it, don’t dismiss them. Their nose may actually be picking up something yours isn’t—or you may both be smelling the same thing and simply describing it differently.

Martine Davis, BBEC

Indoor Environmental Testing, Inc.
We detect what you suspect.

Scientific references:
Sorokowski, P., et al. (2019). Sex Differences in Human Olfaction: A Meta-Analysis. Frontiers in Psychology, 10, 242.

Doty, R. L., & Cameron, E. L. (2009). Sex Differences and Reproductive Hormone Influences on Human Odor Perception. Physiology & Behavior, 97(2), 213–228.

Carpeting in a basement often creates problems because the environment is fundamentally different from upper floors. Concrete slabs routinely transmit moisture vapor from the soil below, even when there is no visible water intrusion. Basements also tend to run cooler, which means warm indoor air can condense on or within materials near the floor. Carpet and padding are porous and absorbent, so they hold that moisture rather than allowing it to dry. Over time, this creates conditions where mold and bacteria can develop out of sight, and odors can build up without an obvious source.

Another issue is that carpet systems hide what’s happening underneath. On a hard surface, moisture problems are usually visible—discoloration, efflorescence, or damp spots. With carpet, those warning signs are concealed. The padding can stay damp for long periods, especially in low-airflow basement conditions. If a small leak, minor seepage event, or elevated humidity occurs, the carpet can become a reservoir for microbial growth. By the time a musty odor is noticeable, contamination may already be established within the carpet and pad, making simple cleaning ineffective.

The EPA advises against installing carpet in basements or any areas with chronic moisture problems.

If You Still Want Carpet: What Must Be Done First

If carpeting is going to be installed over a basement slab, moisture control has to be addressed first. This starts with verifying that the slab is dry using appropriate moisture testing, not just visual inspection. A continuous vapor barrier should be installed between the concrete and the finished flooring system to limit moisture migration. In many cases, a raised subfloor system that creates an air gap between the slab and the carpet is advisable. Dehumidification is also essential—basements should typically be maintained in the 40–50% relative humidity range year-round to reduce the risk of condensation and microbial growth.

Material selection and maintenance practices also matter. If carpet is used, it should be paired with moisture-resistant or low-absorbency padding rather than traditional foam padding that readily retains water. The space should have consistent air circulation, and any signs of moisture—odors, dampness, or spills—should be addressed immediately. Even with these precautions, carpeting remains a higher-risk flooring choice in basements.

Better Flooring Choices for Basements

For homeowners looking to reduce mold risk, non-porous or moisture-tolerant flooring options are generally a better fit for below-grade environments. Sealed concrete is one of the most reliable choices, as it eliminates layered materials that can trap moisture and is easy to clean and monitor. Luxury vinyl plank (LVP) and luxury vinyl tile (LVT) are also commonly used because they are water-resistant and do not absorb moisture like carpet or wood products.

These materials can perform well when installed over a proper vapor barrier and are less likely to support mold growth.

While LVP and similar products are often marketed as “waterproof,” that only applies to the material itself—not the conditions beneath it. If there is not an adequate vapor barrier between the slab and the flooring system, moisture can accumulate underneath the planks. This creates a concealed environment where mold can grow on the underside of the flooring or on the slab surface. In these cases, homeowners may notice a persistent musty odor even though the flooring looks clean.

Proper installation—including moisture testing and use of a continuous vapor barrier where needed—is critical to avoid these issues.

Additional Low-Risk Options

Other alternatives include ceramic or porcelain tile, which are highly resistant to moisture and durable over time. If a warmer surface is desired, removable area rugs can be used on top of hard flooring rather than installing wall-to-wall carpet. This allows for easier cleaning and removal if moisture issues arise. In situations where a finished look is needed but moisture remains a concern, engineered subfloor panel systems paired with moisture-resistant finishes can provide a more controlled assembly.

Final Thought from a Building Biologist 

“Basements don’t behave like the rest of the house. When you put absorbent materials like carpet directly over concrete, you’re often creating a hidden moisture trap. The problem isn’t always visible—but the air quality impact is real.”
— Martine Davis, Certified Building Biologist

Regardless of the flooring choice, controlling humidity and managing water at the source remain the most important factors in preventing mold in basement environments.

Environmental illness rarely begins dramatically.

It begins subtly.

A little more fatigue.
A sinus infection that doesn’t resolve.
Difficulty concentrating.
Sleep disturbances.
Mild anxiety.
Headaches that feel “off.”

You adjust your routine. You push through.

Then months pass.
Sometimes years.

Doctors test. Labs return normal. You’re told stress may be a factor.

Eventually, someone suggests mold.

You hire an inspector.

And the report says:

“No significant findings.”

This is where doubt sets in.

If the home is clean, why are you getting worse?

At Indoor Environmental Testing, Inc., we work with many individuals who have walked this debilitating path. They are not looking for validation of fear. They are looking for resolution.

And one of the most frustrating aspects of environmental illness is how often homes “test clean.”

Why Homes Test Clean When They Aren’t

There are several reasons.

1. Sampling Was Limited

One or two general air samples cannot represent:

• Wall cavities
• Ceiling spaces
• Insulation
• Subflooring
• HVAC interiors
• Soft furnishings

If those areas were not investigated, they were not ruled out.

2. Mold Was Dormant or Not Aerosolized

Mold does not constantly release spores at the same rate. If sampling occurred during low disturbance conditions, air results may appear normal despite reservoir contamination.

3. Health Context Was Ignored

A spore count interpreted as “normal” for the general population may not be tolerable for someone with environmental sensitivity.

Without considering the client’s health history, interpretation can be misleading.

4. The Investigation Was Visual, Not Analytical

If nothing is visible, many inspectors stop there.

But hidden contamination does not advertise itself.

The Emotional Toll

Being told “everything looks fine” while your health declines creates a unique psychological burden.

You question your perceptions.
You hesitate to bring it up again.
You begin to feel isolated.

We have heard this story countless times from clients in Nashville and Madison.

The debilitating path of environmental illness is not just physical. It is emotional.

And when inspections fail to uncover the problem, that burden intensifies.

What Advanced Investigation Requires

True environmental investigation is not about checking boxes.

It is about:

• Listening carefully to symptom patterns
• Identifying environmental timelines
• Evaluating hidden assemblies
• Assessing building science factors
• Testing strategically, not generically

It requires recognizing that some homes “test clean” because they were never truly examined.

You Are Not the First to Walk This Path

Many of our clients arrive after years of searching.

They are informed.
They are cautious.
They are skeptical.

They do not need basic education.

They need someone willing to go further.

We cannot promise that every home has contamination.

But we can promise that if contamination exists, we will pursue it thoroughly.

Because when someone’s health is declining, “probably fine” is not an acceptable conclusion.

When investigating mold contamination in buildings, many inspectors rely on spore trap air samples. While spore testing can provide useful information, it often misses an important part of mold exposure: microscopic fungal fragments.

Research over the past two decades shows that fungal fragments can be far more numerous than intact spores, and these particles often contain β-glucans, a key biomarker of fungal material.

Because of this, mold beta-glucan testing is increasingly used in indoor air quality (IAQ) investigations to detect hidden fungal contamination that traditional spore counts may overlook.

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What Are Beta-Glucans?

β-glucans are structural polysaccharides found in fungal cell walls. They are present in:

• Mold spores
• Fungal hyphae (the branching structures that form mold colonies)
• Fungal fragments and microscopic debris

When mold grows on building materials or when moldy materials degrade, these particles become airborne or settle into household dust.

Because β-glucans are part of the fungal cell wall, they serve as a marker of total fungal biomass.

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Why Mold Beta-Glucan Testing Matters

Traditional mold testing methods measure only intact spores. However, multiple studies have shown that spores represent only a portion of airborne fungal particles.

Research by aerosol scientists Dr. Tiina Reponen, Dr. S. A. Grinshpun, and colleagues demonstrated that fungal fragments can be released during mold growth and mechanical disturbance.

In controlled aerosolization experiments, researchers found that fungal fragments could outnumber spores by hundreds of times (Górny et al., 2002).

These fragments often measure less than 1 micron, allowing them to penetrate deep into the lungs.

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Scientific Evidence Behind Beta-Glucan Testing

Several major studies have established the importance of fungal fragments and β-glucans in indoor environments.

Fungal Fragments as Indoor Air Biocontaminants

Górny RL, Reponen T, Grinshpun SA, Willeke K.
Applied and Environmental Microbiology (2002)

This landmark study demonstrated that fungal fragments are released along with spores and may occur at concentrations hundreds of times higher than spores.

Citation:
Górny RL, Reponen T, Willeke K, Schmechel D, Robine E, Boissier M, Grinshpun SA. 2002. Fungal fragments as indoor air biocontaminants. Applied and Environmental Microbiology 68(7):3522-3531.

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Fungal Fragments in Moldy Houses

Reponen T., Adhikari A., et al.
Atmospheric Environment (2007)

This field study measured airborne fungal fragments in mold-affected homes and confirmed the presence of submicron fungal particles in indoor air.

Citation:
Adhikari A, Reponen T, Grinshpun SA, Martuzevicius D, LeMasters G. 2007. Fungal fragments in moldy houses. Atmospheric Environment.

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Beta-Glucans and Respiratory Health

Rylander R.
Indoor Air (1997; 2010 reviews)

Dr. Ragnar Rylander conducted pioneering work on β-glucans as inflammatory agents, demonstrating their role in respiratory irritation and immune activation.

Citation:
Rylander R. 1997. Airborne β-glucan and respiratory disease. Indoor Air.

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Together, these studies established that fungal fragments containing β-glucans are a major component of indoor mold exposure.

According to the EPA “Allergic reactions to mold are common and can be immediate or delayed. Repeated or single exposure to mold, mold spores, or mold fragments may cause non-sensitive individuals to become sensitive to mold, and repeated exposure has the potential to increase sensitivity”.

 

Spores vs Fungal Fragments

Traditional mold tests primarily measure spores, but buildings also contain many microscopic fragments.

Because fragments are often much smaller than spores, they remain airborne longer and can travel throughout buildings.

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What Mold Beta-Glucan Testing Detects

β-glucan testing measures total fungal biomass, including:

• Spores
• Hyphal fragments
• Degraded fungal debris
• Microscopic fungal dust

This makes it useful for detecting hidden mold problems.

Common scenarios where beta-glucan testing helps include:

Hidden Mold in Wall Cavities

Mold growing inside walls may release fragments even when spores are not detected.

Post-Remediation Evaluation

Beta-glucans can identify residual fungal dust remaining after remediation.

Buildings with Symptoms but Low Spore Counts

Occupants may react to fragments rather than spores.

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Laboratories Offering Mold Beta-Glucan Testing

Several environmental laboratories offer β-glucan analysis for indoor air quality investigations.

EMSL Analytical

Large international environmental laboratory.

Typical price:
$80 – $150 per sample

Services include:

• Dust beta-glucan analysis
• Air filter analysis
• Environmental microbiology testing

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Eurofins EMLab P&K

One of the largest mold testing labs in North America.

Typical price:
$100 – $180 per sample

They provide a full range of IAQ services including:

• mold spore analysis
• fungal biomass markers
• building investigations

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Mycometrics

Specialized microbial testing laboratory focusing on fungal contamination.

Typical price:
$120 – $200 per sample

Offers assays for fungal biomass markers including β-glucans and ergosterol.

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Environmental Diagnostics Laboratory (EDLab)

Environmental testing laboratory providing advanced IAQ analyses.

Typical price:
$100 – $200 per sample

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Limitations of Beta-Glucan Testing

While beta-glucan testing is useful, it does have limitations:

• It does not identify specific mold species
• It cannot determine whether contamination is active or historical
• Small amounts may originate from non-fungal organic materials

Because of these limitations, most investigators use beta-glucan testing alongside other diagnostic methods.

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Best Practice for Mold Investigations

The most effective building investigations combine several techniques:

• Visual inspection
• Moisture mapping
• Spore trap air sampling
• Dust testing (ERMI / HERTSMI-2)
• Mold beta-glucan testing

This multi-method approach provides a more complete understanding of fungal contamination.

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Final Thoughts

Scientific research over the past two decades has shown that mold exposure is not limited to spores. Microscopic fungal fragments—often containing β-glucans—can be present at much higher concentrations and may play an important role in indoor air quality and occupant health.

Because of this, mold beta-glucan testing is becoming an important tool for detecting hidden mold contamination in buildings.

For inspectors, industrial hygienists, and building scientists, beta-glucan testing can provide valuable insight into total fungal biomass and residual mold contamination that traditional testing methods may miss.

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Key References

Górny RL, Reponen T, Willeke K, et al. 2002. Fungal fragments as indoor air biocontaminants. Applied and Environmental Microbiology.

Adhikari A, Reponen T, Grinshpun SA, et al. 2007. Fungal fragments in moldy houses. Atmospheric Environment.

Rylander R. 1997. Airborne β-glucan and respiratory disease. Indoor Air.