How to Recognize Harmless "Cosmetic" Mold in buildings InspectAPedia® -
How to identify cosmetic & other low-risk or harmless black and other colored mold in buildings
Age of mold: how to determine that mold has not been actively growing on building framing
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This article discusses how to recognize mold that may be harmless, or cosmetic only in importance in buildings.
We look for mold in buildings not only where mold is visible but also by context: where do we see leak stains,
or where do we see building practices most likely to have produced a hidden leak or moisture problem? Ice dam leaks in walls,
hidden plumbing leaks, roof spillage by the foundation, are all common clues that often track to a wet building wall or ceiling cavity and
from there to a hidden mold problem which may need to be addressed.
Readers should be sure to also review more details about harmless mold at HARMLESS BLACK MOLD.
How to Recognize Harmless Cosmetic Molds and Other Low-Risk Molds
On occasion some visible mold can be determined to be harmless and "cosmetic" old mold that was present when the building was constructed.
While it is always possible that additional more harmful molds are present in addition to the cosmetic mold, if there is no leak history
nor any other evidence of mold growth in a building and if there are no health or building-related occupant complaints, the identification
of the cosmetic mold described here might be accomplished by visual inspection alone, saving on more costly professional mold tests.
Cosmetic-only Ceratocystis/Ophistoma bluestain mold is shown on the floor joists in the new construction framing in the photo
just above. This is a harmless, cosmetic-only mold that does not damage the lumber and is not a pathogen
for humans. Here's a good example of the observation that not all "black mold" is "toxic black mold". It will be totally
hidden when the ceiling drywall is installed.
The mold shown in the photograph above is plain to see during construction, but will be covered and hidden completely when
the contractor installs the ceiling drywall.
One of our clients discovered this scary-looking black mold during a renovation and was quite
concerned that a major toxic black mold reservoir had been found in the building.
He client was
facing a very costly mold cleanup project if this mold had to be addressed as a toxic material. Luckily this was not the case in this
instance, as was easily demonstrated both by a simple inexpensive lab test and confirmed by onsite inspection of
other framing details discussed at "Cosmetic Molds" linked-below.
So sometimes the mold in your house might be only a cosmetic concern.
"Bluestain" or
Ceratocystis/Ophistoma is common on framing lumber and we often find it in attics on the
under side of roof sheathing. Unless it's in finished portions of living space where it creates
a cosmetic problem, no particular action needed to address this black mold.
Detailed advice about spotting harmless black mold including how to determine by visual inspection
alone whether or not you're probably looking at one of these common framing lumber cosmetic molds
is at HARMLESS BLACK MOLD.
Warning notice about Cleaning Up Mold Yourself
Guidelines defining what's a "large amount" of mold and what's reasonable for a
homeowner to handle have been published by several states including New
York and California. Links to some key documents describing mold cleanup and mold remediation procedures
are at MOLD CLEANUP GUIDE- HOW TO GET RID OF MOLD
People who
are allergic, asthmatic, infant, elderly, immune-impaired, etc., should not disturb mold and should
not be in the area where mold remediation is being performed. Consult with your doctor, health
department or other professional before tackling this job yourself.
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Additional technical contributors & reference sources for this article are listed below.
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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp
"A Brief Guide to Mold, Moisture, and Your Home",
U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
Allergen Tests in buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building
"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA
http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.
Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases
Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests
Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
Rodent control issues, including dander, fecal, and urine contamination of buildings and Building insulation are discussed at our
Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources
Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon)
Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination
Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html
"Disease Prevention in Home Vegetable Gardens,"
Patricia Donald,
Department of Plant Microbiology and Pathology,
Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202
Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.
OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold
Mold or allergens may not be the only or even the main indoor environmental contaminant. Don't let media attention to mold
cause so much enviro-scare fear that other, possibly more urgent hazards go un-addressed.
Ozone Warnings - Use of Ozone as a "mold"
remedy is ineffective and may be dangerous.
Pet control - if you can't say goodbye to your bird, cat, dog, guinea pig, hamster, tropical fish, then limit the
areas they occupy and limit the airflow from that area to sleeping or other areas of the building, use allergenic
bedding, eliminate wall-to-wall carpeting, improve housecleaning including use of a HEPA-rated vacuum cleaner. For more details
see our article Dog, Cat, and Other Animal Dander - Information for Asthmatics and Indoor Air Quality
Rodents, Mice, Squirrel Control - I find high levels of mouse and rodent dander, fecal dust, and urine-contaminated dust in some buildings,
and high levels of these materials in building insulation in those locations. If you have a mouse problem, particularly if mice and their waste (fecals or urine) are contaminating
the building HVAC or building insulation, may need both steps to clean up or remove infected materials and steps to stop an ongoing
rodent problem. If squirrels are a problem, the cleanup needs to include closing off entry openings into the building. Get some
help from a licensed pest control expert.
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