Apartment buildings may look crisp outside but individual rental apartments may be discovered by their tenants to have suffered leak damage and extensive hidden mold - here we give some basic advice Guide to Hidden Mold in Rental Homes, Apartments, Offices

  • HIDDEN MOLD RISKS for RENTERS - 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 or Hidden mold contamination complaint advice for landlords
  • POST a QUESTION or READ FAQs about hidden mold problems in rental apartments
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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

Photograph of - Black mold on drywall, green mold on drywall and trim, were hidden behind the paneling  in
this apartment bathroom

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.

Moldy apartment (C) Daniel Friedman

Rental Unit & Tenants Guide to Mold & Indoor Environmental Hazards


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