I have reviewed far too many reports that site an interstitial/wall cavity sample as the reason that a building or home requires extensive if not complete remediation. The cases brought to me have increase recently at an alarming rate. Some of these samples have been collected on homes and buildings on crawl spaces that were built as much as 75 years ago.
All of the reports that I have reviewed included very little background information and all had no elevated spore trap levels in the living/occupied space. A few identified elevated moisture but none identified the cause and origin of the moisture. All fell to the collection of air samples within several walls for a period of 5 minutes at a rate of 15 liters to provide the clients with a smoking gun and an answer to what in their home or office was making them sick.
I believe the samples are collected in an attempt to justify the cost of the assessment by providing some form of a conclusion via laboratory results.
If anyone out there is collecting wall cavity air sampling please help me understand how costly remediation can be based on these samples alone. More specifically why anyone would collect a wall sample from a 75 year old building on a crawl space with openings from the crawl space to the wall cavity. A lath and plaster wall cavity at that. Then recommend remediation and further investigation.
But then again I prefer to sample as little as possible during the initial investigation.
Just venting a bit
P.S. My clients are the property owners and/or the property management company. The reports were all from tenant hired inspectors.
•John P. Lapotaire, CIEC
•Certified Indoor Environmental Consultant
•Microshield Environmental Services, LLC