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Should Exposed Fiberglass Insulation Be Used Below Grade or in HVAC systems? -- Jeff May

Exposed fiberglass insulation in basements and crawl spaces and exposed fibrous lining material in mechanical systems can be riddled, often invisibly, with mold-growth. This presentation discusses such problems, includes photographs, micrographs, and case studies and ways to avoid them. The section on fiberglass insulation below-grade covers testing methods and results of one study, mold problems endemic to finished and unfinished basements as well as crawl spaces, and mites that can be found foraging in mold growth. Questions to be discussed include: Why does mold grow in such fiberglass? Can basements ever be mold free? Should crawl spaces be vented to the exterior or be part of a duct system? The section on exposed fibrous lining material in heating and cooling equipment will include studies of the problem and health issues caused and cover the where and why, and how to avoid. Filtration will be a major topic in this part of the presentation. The construction and HVAC industries have to wake up to the fact that their practices are leading to mold growth that in turn can sicken building occupants. The presentation will stretch indoor air quality professionals’ knowledge of building science and home inspectors’ knowledge of indoor air quality issues, including mold. Learning goals: Participants will learn (1) novel ways to identify mold problems in fiberglass and (2) how to avoid these problems; they will also learn (3) the true importance of filtration in HVAC systems and (4) the ways in which contaminated systems affect health. Jeff May, Principal Scientist of May Indoor Air Investigations LLC in Tyngsborough, MA, has been investigating residential IAQ problems for over 25 years and has collected and examined by microscopy over 40,000 air and dust samples. He is author or co-author of 4 books on IAQ, published by Johns Hopkins University Press: “My House is Killing Me!” (2nd edition due in Fall 2020); “My Office is Killing Me!”; “The Mold Survival Guide”; and “Jeff May’s Healthy Home Tips.”