Show Resources:
Danny Gough 12:07 PM
the handheld calculator
Charles Leahy - Eco-Panels 12:23 PM
For Dr. Joe - would you expect a more air "leaky" house to have greater correlation between poor air quality inside the wall and air quality inside the house?
Charles Leahy - Eco-Panels 12:34 PM
If there is no mold growth - does that mean that the mold colony is dead? Or is it still viable and alive?
You 12:07 PM
Jack Kilby presented his findings to Texas Instruments' management for a discovery for which he was later awarded a nobel prize. What did he invent?
Ed Light 12:43 PM
Wall cavity sampling does not define contamination and is not needed!Visible inspection for suspect growth by borescope or cutting inspection holes is sufficient to determine if remediation is needed. The critical question is health risk. The science establishes that the criteria used to interpret airborne mold sampling data does not determine occupant health risk. The only relevant standard with respect to mold growth is that supported by most public health officials- Visible suspect growth is not acceptable and should be remediated.
Occupant exposure to mold growth in cavities is moisture dependent. Under dry conditions, growth is dormant and exposure is negligible unless disturbed. If moist conditions reoccur, then occupant exposure is likely. In my projects, the potential for cavity growth can be predicted based on current and historical conditions. The extent of visible growth is then determined by inspection of cavity surfaces and growth must be treated or removed.
KISS!!
Charles Leahy - Eco-Panels 12:47 PM
attics can be HOT. I wonder if the second floors are simply providing the heat energy to encourage mold growth on the second level.
ralph froehlich 12:47 PM
Ed-Cutting holes in each wall, even each exterior wall, is expensive to perform, repair and clean up, may involve both asbestos and lead-containing paint, and may miss visible growths. Would you only cut drywall in areas where moisture had already exited the wall at baseboards or carpet tack strips?
Irene Grant 12:54 PM
Clinical specimens are cultured at lower temps to isolate molds.
Ed Light 12:56 PM
Elevated moisture readings in cavities is not acceptable. Where trapped moisture is likely, hidden surfaces must be dried or future mold growth is likely.
IAQ RADIO+
Show Number: 762
Joe Spurgeon, PhD
Danny Gough
Mold in wall cavities; a growing Issue?
Good day and welcome to IAQ Radio+ episode 762 blog. This week we welcomed Dr. Joe Spurgeon and Danny Gough to discuss issues with moisture and mold in wall cavities and to provide answers to questions: Is mold commonly found in wall cavities? Is mold in wall cavities a growing problem? What causes mold inside wall cavities? Is mold inside of wall cavities geographically variable? How do you sample for and explain findings to clients?
Joe Spurgeon, PHD, has a multidisciplinary doctorate degree in Analytical Chemistry and Environmental Health from the University of Pittsburgh; and was a Certified Industrial Hygienist from 1993 – 2013. His career has included working as a research chemist on the NBS Lead-Paint Poisoning Program, directing the FAA’s Combustion Toxicology Laboratory, performing Health Assessments for CDC/ATSDR, implementing US EPA’s Laboratory Exposure Assessment Project, and working as a consultant specializing in microbial indoor air quality for US PHS. He has performed numerous residential and commercial investigations involving water intrusions and microbial contaminants; has taught courses on mold investigations, sampling, and data interpretation methods; and has served as an expert witness in numerous mold cases. His books are available at http://expertonmold.com/
Danny Gough calls himself a slow learner trying to retire. He works out of Yadkinville, NC and his specialties include Building Performance Consulting, Psychometric analysis and advanced humidity control, Design of HVAC systems for Low Energy Buildings, Geothermal, Solar, Radiant, and Service hot water. Mr. Gough is also an Approved Instructor for the National Association of Home Builders (NAHB) and the Air Conditioning Contractors of America (ACCA). He also provides continuing education Instruction for American Institute of Architects (AIA) and for builders for the NC licensing board for General contractors.
Nuggets mined from this week’s episode:
Danny, what got you interested in this subject? I’m encountering moisture and mold problems in homes where owners are cooling their homes to 65⁰ F-68⁰ F and water is visually dripping out of wall switches and electrical outlets.
Joe, do you opine that wall sampling a good technique? Yes, wall sampling is a good technique, unfortunately it is often used inappropriately. Wall sampling demonstrates building related fungal contamination NOT occupant exposure. Joe’s experience is that what is in the wall cavity, stays in the wall cavity.
Comments from Joe and Danny:
Joe uses PCM filter cassettes. Errors in sampling volume can exceed 20% factor
When sampling a suspected leaky window, Joe samples 50% on left side and 50% on right side.
Joe prefers aggressive sampling, using palm of hand or rubber mallet to tap on wall during sampling. Don’t use a black mallet on white walls!
Two options drive mold amplification inside wall cavities: 1) Infiltration of humid air from outdoors OR 2) water damage history.
Joe’s experience on wall cavities sampling is based upon newer homes.
Danny’s experience is that mold in wall cavities is a problem in newer homes and is NOT a problem in older homes.
Joe Spurgeon's slide presentation is attached below.
Trivia:
On Sept. 12, 1958, Jack Kilby presented his findings to Texas Instruments' management for a discovery for which he later was awarded the Noble Prize. What was this invention?
Answer: Integrated circuit
