When to hire a professional to investigate a building for toxic mold InspectAPedia® -
Five rules of thumb help decide when a mold professional is needed
How to assess the risk of an indoor mold problem in order to decide when mold inspection & testing are needed
How to avoid conflicts of interest when hiring mold companies to inspect or test for mold contamination
Advice from U. Minnesota & other mold cleanup experts
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Five simple "rules of thumb" can help you decide when a mold problem in a building merits hiring a professional to investigate or clean
up mold or other allergens. A mold professional may have some neat gadgets to find or test for mold, but a real expert knows that a thorough building inspection and an understanding of
how buildings work and where they leak, as well as an understanding of mold itself, are critical in finding hidden mold problems and in
specifying the cleanup work needed.
We emphasize that for small areas of mold contamination, generally where less than 30 square feet of contiguous mold is present, simple building cleaning and renovation procedures are all that's needed and testing is usually not appropriate. Most building mold contamination falls in this first category. At DO IT YOURSELF MOLD CLEANUP we provide suggestions for a do-it-yourself cleanup of small areas of mold. At MOLD TEST REASONS we discuss when it is appropriate to test for mold.
These guidelines aid in protecting the building occupants not only from potential health concerns but also from
inappropriate expenses. This document provides information about how to decide when to hire a professional to investigate for the presence of allergenic and toxic mold in
residential or office buildings. Home buyers or home owners who are concerned about mold and who are considering a mold "test" should read the following articles with care:
WHEN TO HIRE A MOLD TESTING PROFESSIONAL - Five Rules of Thumb for Deciding When to Hire a Professional to Inspect for Mold & Prepare a Mold Remediation Plan
The purpose of this article is to help readers decide when it is appropriate to perform mold inspection and testing on a building. We want to know how and when mold testing is appropriate, and we want to avoid spending money on mold testing when it is not necessary. Also we want to avoid spending money on unreliable mold "tests" and inspections that do not validly support any conclusion about the building.
Our moldy home photograph (above, left) shows a cup fungus growing along the wall/floor baseboard trim in a home that had suffered a prolonged plumbing leak. The visible fungal growth is quite obvious. What is less obvious, and what will require an expert inspection, is the extent of mold cleanup needed in the building, possibly including hidden mold in wall and ceiling cavities.
To be effective and to produce advice which is based on more than a wild guess,
building investigations for mold, allergens, gases, or other indoor air quality
concerns must take a broad approach to site and building examination
for probable sources of moisture, bioaerosols, toxic/allergenic mold, or other
allergens.
In order to have some confidence that we understand the building,
how it works, where the risks and problems lie, we examine at the entire
structure, inside and out, and its mechanical systems are examined as well.
Partial inspections, like partial remediation, risk the cost of having to repeat
the process if it was not proper and complete the first time.
In the photo above, though not much mold is visible on the drywall, the presence of
fungal fruiting bodies or "mushrooms" growing indoors at the wall baseboard trim tells
us that this building was very wet for some time - professional inspection is needed
to define the location and extent of moldy material removal and cleaning.
If your ONLY concern is the identity of the mold you've already seen, and if
you are confident that there is not a possible problem elsewhere on the
property, you could simply send a mold sample to our lab (or to any mold lab) for determination. Instructions for an inexpensive and easy way to test mold or to screen settled dust for mold are at http://InspectAPedia.com/sickhouse/bulksamp.htm .
Here are five reasons to consider a more extensive on-site investigation for
toxic or allergenic mold:
People in the building are at
particular health risk: elderly, infant, immune-impaired, asthmatic, history of
respiratory illness or other medical complaints which might be caused by
or aggravated by mold, allergens, or other bioaerosols
People in the building are sick and there is reason to suspect that the building is causing or contributing to health, air quality, or similar concerns. You need a building or apartment evaluation and diagnosis to answer the question that may be posed by your doctor: might the building be contributing to or causing these complaints?
The building has or is
suspected of having had a history of significant leak events or even a single event which
flooded some areas: plumbing leaks, roof leaks, ice dam leaks, basement
water entry, sewer backup, ventilation problems, air conditioning system
problems; forced-air central heating/cooling concerns. If hidden building cavities have been wet, the mold you see may be just the tip of a "mold iceberg" that does need an expert to find the extent of mold, cause of mold, and to remove the mold.
Large areas of water damage or mold contamination have
been seen and you need an estimate of the extent of demolition and mold
remediation which will be needed to make a proper cleanup and repair.
Small mold problems: If
you are confident that the amount of mold is less than 30 sq. ft. of
contiguous mold (and that there is no significant risk of a larger hidden mold problem) then the NY City mold remediation guidelines suggest that
professional remediation is not appropriate. You do not need to hire someone other than perhaps a handyman or general cleaning service. BEWARE: if during cleanup of a small mold problem you discover that it is actually a large one, stop work and bring in a professional to advise you on how to proceed.
Large mold problems: If more than 30 sq. ft. of mold-infected material is found or is already visible, then you
need professional advice as more serious health risks and mold contamination may be involved.
Contractors have already bid a
variety of expensive mold-cleanup approaches to building cleanup/remediation and you need an
unbiased, informed professional to help sort out these proposals
Should You Clean Mold in Advance if You ARE Going to Hire a Mold Expert
If you are thinking of hiring a professional to inspect, diagnose, and test your building for mold or other problems we prefer that you do NOT conduct a "do it yourself" cleanup ahead of time. Cleaning up the mold that you see does not preclude an expert's ability to find areas of suspicion or even to find mold, but
Cleaning up the mold you see may remove some easy-to-identify materials that are useful to compare with what we find in other screening measurements find in the building - that is, it's useful to know some apparent sources of particles that we may later find in screening samples in the building.
Contamination risk: Cleaning up a large area of mold risks cross-contamination of other areas in the building
Illness risk: Doing a large mold cleanup without taking proper precautions could make someone sick
If you're not able or interested in hiring a mold professional, and/or especially if the total known moldy area is small
Remove small mold areas yourself: For small areas of mold, it's appropriate to just remove it - if you are sensitive, fragile, or sick, have someone else do the work.
Collect and hold on to some samples. If you're going to proceed anyway, try collecting some tape samples of what you see. Instead of sending these samples off to a lab, just keep the samples, but prepare them by following the sample collection instructions at Six Easy Steps to Get and Mail a Mold Test Kit - you can always save them to give to an investigator later if it becomes necessary to investigate further
If you stumble onto a large area of mold during your cleanup (more than 30 sq ft) you should stop and consult an expert
CONFLICTS OF INTEREST: Take Care in Hiring Mold Contractors: Avoid Conflicts of Interests
How to avoid conflicts of interest during a mold remediation project: the person who evaluates your property to tell you what (possibly costly) cleanup work
is needed certainly should not be the same person who is going to perform that work.
Similarly, after a mold cleanup has been
completed, the person who inspects and tests to certify that the work has been done properly should have no connection with the
company who performed the cleaning.
In the photo the author is examining a very moldy basement. He will find the extent of cleanup needed, perform appropriate
testing in this and other building areas, and will assist the homeowner in evaluating the results of the cleaning effort.
But it
would be unethical and a conflict of interest for the investigator who is going to specify what mold remediation cleanup work is needed in a building to also offer to perform the cleanup work itself.
U. Minnesota general rules of thumb for deciding when to inspect for mold
IF these conditions are present in a building being evaluated for mold contamination risk
Fungal spore count or visual
presence indicators are high (air or bulk) [DF comment: BEWARE: while a high indoor spore count probably does indicate a problem, a low indoor airborne mold count is not a reliable clean bill of health for a building. See ACCURACY OF AIRBORNE MOLD SPORE COUNTS.]
Fungi indoors are different
from outdoors or non-complaint control areas.
Fungi are allergenic or toxic
The area is likely to be
disturbed
There is or was a source of
water or high relative humidity, AND
People are occupying the area
or have contact with air from this area
There are immune compromised
individuals or individuals with elevated sensitivity to molds
[DF Comment: we add other examples of people at special risk: elderly, infant, asthmatic, COPD sufferers]
THEN mold may be a problem in the building. -- N. Carlson, U. Minnesota [Comments added by DF]
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Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. (727) 595-4211 mark@BestTampaInspector.com 03/31/2009
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