Guide to Hidden Mold in Rental Homes, Apartments, Offices InspectAPedia® -
Guide to hidden mold in rental properties
The mold you see or the mold you tested may not be the only concern nor the main risk
How to handle hidden or "non-visible" mold contaimnation complaints or problems in rental property, apartments, rental homes, offices
Hidden mold contamination testing advice for rental tenants
Hidden mold contamination complaint advice for landlords
This article describes the steps that a tenant in a rental apartment or rental home can take to look for and test for
hidden mold contamination, we discuss when such testing is appropriate, and we make suggestions on how to inform building management of a mold problem, what to expect the rental property managers to do if they
are going to address a mold problem properly, and what the rental apartment tenant needs to watch out for during
a mold investigation and mold remediation of their home.
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A Guide to Possible Hidden Mold in Rental Apartments, Houses, Offices
The mold that you *see* may not by any means be the whole problem, or even much of the problem; various species could be
in building cavities and in the HVAC system.
Too often we find that "black mold" on building surfaces has received attention but hard-to-see Penicillium sp. or Aspergillus sp. (for example) remain in large reservoirs on building surfaces or in insulation.
Magic bullets: Also, "bleaching mold" or "fogging" or "encapsulating" mold is never a successful remedy for a moldy building.
The places where mold is growing must be found, moldy material removed, exposed surfaces cleaned, and the causes of mold
growth corrected.
If the area of mold growth is large (more than 30 sq ft) the work needs to proceed with special
procedures to avoid spreading moldy dusty debris around.
Tenant-identified possible mold reservoirs
The tenant or building maintenance staff may have already identified apparent mold reservoirs or sources, and of course there could be other sources from other leaks or problems they haven't
discovered:
Roof leaks - can have leaked into ceilings and walls; depending on what building materials used, they could be moldy with
problem molds.
HVAC systems - If there is a common A/C duct system which has become mold contaminated, no amount of cleaning in your immediate
apartment would be sufficient since it is possible that the whole system needs to be cleaned, or possibly some duct
sections replaced, and the cause corrected. Also it is common for A/C condensate or water from a chiller system to
leak; water could have leaked into your closet ceiling and walls, also creating a problem mold reservoir.
Building insulation - often building insulation has become mold contaminated but looks "clean" to the naked eye. Few mold inspectors test this material, yet it is often discovered to be the principal problem mold reservoir in some building areas.
Very often when I visit a site I find other leaks and mold sources that need to be addressed, so I wouldn't assume these
are the full extent of what needs attention.
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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.
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