MOLD questions

The basic inspection will attempt to identify defects, moisture issues and conditions conducive to mold and decay that are detectable within accepted inspection standards. Unusual and dangerous mold will generally not exist if all systems of the house are correct and functioning properly. These systems are included in my basic inspection.

Beware of those claiming to be “Certified” mold inspectors.

Home inspection standards do not include identification or testing for molds. That is an extra, specialty service. Some home inspectors offer mold inspections and testing as a sideline. I have chosen to leave this to the specialists whose main or only business is environmental inspection. Any home inspector can become a mold or radon “specialist” by taking a few hours of on-line classes and a self administered, “open book” test, or attending a 1 to 3 day course. My philosophy and experience both as a builder and an inspector is that specialty areas are often, best left to the specialists. I don’t think I would be comfortable if my general physician also claimed to be a specialist for all health concerns. As a general contractor, I have personally done most of what it takes to build a house, including electrical, plumbing, roofing, wall board, etc. It doesn’t give my clients the best service to represent myself as an expert in all disciplines of this complicated business.
In most cases, it seems to be a waste of money to do mold sampling and testing.  There is more involved in determining if you have a serious mold issue than having a few samples lab tested. There are many variables and these tests can be highly unreliable and misleading. The only person who is truly qualified is someone with advanced education and training as a hygienist and air quality specialist.
In my opinion, if a home inspector is actively promoting mold investigations and testing and offering to do it for a fee, it could be motivated more by increasing their bottom line than by protecting their clients.
Seriously consider it before you hire a general home inspector to be an all inclusive specialist. Being a knowledgeable, competent generalist is a specialty unto it’s self.
These links will give you hundreds of pages of information regarding Mold issues.

What are “toxic molds”?  Some molds are referred to as “toxic molds” because under certain conditions, they can produce mycotoxins. Mycotoxins are compounds “produced by fungi that are toxic to humans or animals and have economic impact.” (Ciegler, 1980). Many common molds can produce mycotoxins. Those that arbitrarily have been cited as “toxic molds” include Stachybotrys chartarum (or atra), and various species of Aspergillus, Fusarium and Penicillium.

Mycotoxins are secondary metabolites. This means that the mold does not need to produce mycotoxins to grow or survive. Mycotoxins are produced only when certain environmental conditions are in place and when produced are found in extremely small quantities on a per-spore basis. Mycotoxins are contained in the spore itself and also may be found in the substrate or material in which the mold is growing (Jarvis, 1986).

The isolation of a mold typethat has shown to produce toxins (“toxigenic” species) does not substantiate the presence of mycotoxins(Ren, 1999). For example, known mycotoxin-producing strains of Aspergillus flavus and A. fumigatus were grown on various building and construction materials. No mycotoxins were found in extracts of densely colonized ceiling tiles, wallboard, wallpaper and air filters. These negative results were obtained even with enhanced growth when the indoor construction and finishing materials were supplemented with carbon and nitrogen (Tuomi, 2000).

Mycotoxins are relatively large and heavy molecules (Schiefer, 1990; WHO, 1990). This means they are not volatile and do not evaporate from the mold spore or substrate particle. The musty odorassociated with mold comes from volatile compounds generated as the mold reproduces (Pasanen, 1996). These compounds, which are different from the mycotoxins, may be annoying and irritating, but are not mycotoxins and are not highly toxic.The concentration of the volatile organic compounds (VOCs) is usually too low, even in damp and moldy buildings, to cause sensory irritation symptoms such as burning eyes and upper airway irritation (Pasanen, 1998; Korpi, 1999). However, the odor of these compounds may be noticeable at levels well below the concentrations that might result in sensory irritation(Pasanen, 1996; 1998).

Members of the CDC also performed a review of the available medical literature regarding molds and mycotoxin exposures in the indoor environment, and in the peer reviewed journal for the American Industrial Hygiene Association, the authors concluded:  This review of the literature indicates that there is inadequate evidence to support the conclusion that exposure to mycotoxins in the indoor (nonindustrial) environment is causally related to symptoms or illness among building occupants.    See full report here:

This is an excerpt from the study conducted by a group of physicians in the American College of Occupational & Environmental Medicine, listed below: 

“In recent years, the growth of molds in home, school, and office environments has been cited as the cause of a wide variety of human ailments and disabilities. So-called “toxic mold” has become a prominent topic in the lay press and is increasingly the basis for litigation when individuals, families, or building occupants believe they have been harmed by exposure to indoor molds. This evidence-based statement from the American College of Occupational and Environmental Medicine (ACOEM) discusses the state of scientific knowledge as to the nature of fungal-related illnesses while emphasizing the possible relationships to indoor environments. Particular attention is given to the possible health effects of mycotoxins, which give rise to much of the concern and controversy surrounding indoor molds.
Molds and other fungi may adversely affect human health through three processes: 1) allergy; 2) infection; and 3) toxicity. One can estimate that about 10% of the population has allergic antibodies to fungal antigens. Only half of these, or 5%, would be expected to show clinical illness. Furthermore, outdoor molds are generally more abundant and important in airway allergic disease than indoor molds — leaving the latter with an important, but minor overall role in allergic airway disease. Allergic responses are most commonly experienced as allergic asthma or allergic rhinitis (”hay fever”). A rare, but much more serious immune-related condition, hypersensitivity pneumonitis (HP), may follow exposure (usually occupational) to very high concentrations of fungal (and other microbial) proteins.
The present alarm over human exposure to molds in the indoor environment derives from a belief that inhalation exposures to mycotoxins cause numerous and varied, but generally nonspecific, symptoms. Current scientific evidence does not support the proposition that human health has been adversely affected by inhaled mycotoxins in the home, school, or office environment.”
And from Building Science Corporation‘s Joseph Lstiburek, Ph.D., P.Eng.
who is an ASHRAE Fellow and an internationally recognized authority on indoor air quality, moisture, and condensation in buildings.

“How Do I Know If The Mold is Cleaned Up If I Don’t Test?
The mantra for clean-up is “clean and dry.” If you don’t see it
or smell it on a surface you probably don’t have it. And if you do
have some, even though you don’t see it or smell it you certainly
don’t have much of it. A little bit of residual mold is not a problem
unless moisture is available. Remember, mold is everywhere.
if the clean-up removes 100 per cent of the mold, spores that are
in the air will reintroduce mold back into the cleaned area. The “white
glove test” and common sense are currently the best approach.
No dust and dirt – no mold. ‘If all surfaces are free of debris, dust and dirt they will be free of mold.’
There may be residual mold left in the building that is unseen, but this is acceptable. The object is not to sanitize or sterilize the building. The object is to avoid exposing people to large amounts of mold. Bear in mind that many of the molds that colonize buildings are common in the outdoor air where spore levels may be very high. Even if the clean-up does remove 100 per cent of the mold, outdoor air will quickly reintroduce mold spores into the cleaned area. This is why the underlying moisture problem must be corrected to prevent the recurrence of mold.”

For the full research report see this link:,%20research%20report%200209

The following is a discussion taken from a national inspection association forum:

I have done some research today about mold inspection and the requirements to call yourself such an expert. This stemmed from a realtor that will only use a home inspector that is also representing himself as a mold inspector, which I am not. Therefore I did the fact finding below:

I contacted the these agencies in regards to regulation of companies and certification or licensure of mold inspection: EPA, Contractor’s Board of Oregon, Attorney General of Oregon, DEQ, Building Codes Division of Oregon, OR OSHA, Department of Human Services, HUD, Marion County Housing Authority, Two “mold” inspection businesses in Salem, OR.

After many phone calls and discussion it is clear that there is no standard for “certification” at the state level or the federal level to be a “mold” inspector. There are some ANSI suggestions on how to remediate mold and protect yourself while doing it. Basically, anyone who wants to call themselves a “mold” inspector can,unlike the certification and licensure with the State of Oregon to become a Certified Home Inspector. Typically they get their “certificate” on line from a company selling tools and products for contractors. Since this is the case, the consumer has limited ability to be able to clearly delineate if the inspector they chose really has a good back ground in the area of ‘mold” inspection. This basically comes down to an area of very limited regulation. Ultimately, an Industrial Hygienist is someone who really understands mold, knows how to interpret the readings and what to do to remediate it. There are many companies that feel they have a superior product (TM-100) and service (sometimes a lifetime warranter).

I also called two “mold” inspection companies. They reported that the way they get business is because of the home inspector. The inspector states in his report that there may be mold and defer it to a “mold” specialist. Then the Realtor refers it to the company that they feel is most reputable. They both acknowledged that they do the inspection, then do the remediation even if the home inspector has done an inspection. Therefore, it is entirely possible that you will have a less than respectable individual do the exam for the “mold” then tell the client that there is mold and how much it costs to remediate it. All the while, there may have never been any mold. This may be the extreme possibility, but it is possible. This is why as an Oregon Home Inspector, we are not able to do work on a residence for 1 year after the Whole Home Inspection. If so, we would not be an unbiased opinion on the condition of a residence.

During my discussions with the EPA and OR-OSHA, they feel that there must be a reason to have a mold inspection in the residence. They don’t recommend that a sample be taken on each home sold. Additionally, there are specific conditions that must be noted when the sample is taken. There could be very little mold in the control sample outside the residence as there is on the inside. The other possibility is that the home may have a seasonal mold concern and it shows up in the winter, not during the summer when the home was inspected. Furthermore, the two “mold” inspection companies I researched stated that they do not walk into a home and immediately start taking samples. They look for causes, just like the home inspector. The difference here is that a home inspector does a limited visual inspection. The “mold” inspector may have permission to do destructive discovery. However, in the event that this is a home transaction, I am doubtful that a seller is going to allow a “mold” inspector remove such things as insulation and drywall to investigate the concern. In no way do I represent any Federal, State or Local agency. The above statements are for informational purposes only and should not be used as a standard or guideline on any remediation or inspection of “mold”.

Here are a couple of EPA brochures that are used to inform the public.


I have also made the business decision NOT to represent myself as a mold specialist for many of the reasons you have sighted. Mainly, because there IS no real regulation or standards except that those in the business of selling something have set themselves up to “certify” people. In my opinion, to step outside the umbrella of accepted inspection standards into this area is opening up huge liability, that I choose not to accept. This is an extra service completely outside the scope of a regular inspection.

I don’t know about the Willamette Valley, but here on the coast there is probably some mold somewhere in almost every house. It’s an accepted reality of life in high humidity areas. I personally think that the mold “industry” and the media and advertising hype that is part of it is way over blown. As with any fear that is well marketed, there are opportunists who will milk it for all it’s worth. Don’t get me wrong. I am not saying that there isn’t a real concern about some molds. There definitely are molds that can be toxic and need to be dealt with. The fact is, as stated in medical research, it can be a health issue for some people. The facts are that some people will die if they are stung by a bee, eat nuts or wheat.

The main thing we, as home inspectors, should be looking for are moisture issues that may cause excessive or dangerous mold conditions. If all systems are properly done and functioning, it is unlikely there will be any serious mold issues that would be of concern to most healthy people.

SEE MOLD INFORMATION in the links section on the right side of this page.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s