Jeasto moved into her energy-efficient home just two months ago and is now wondering whether she and her husband are facing a serious air quality problem.
As she explains in this recent Q&A post, the one-story house is extremely tight (tested with a blower door at 0.44 ACH50). It has a conditioned attic where HVAC equipment including an energy-recovery ventilator (ERV) have been installed. The roof is insulated with a mix of closed-cell spray polyurethane foam against the roof deck plus blown-in fiberglass insulation contained behind fabric netting. When the HVAC installer was working in the attic, he disturbed some of the insulation and he complained how itchy he was. At the time, that didn’t register with Jeasto.
“When my husband and I went up there to start storing stuff, we noticed the floor (just OSB) was really dusty, and there were pieces of insulation on the floor and on the tops of the mechanical equipment,” she writes. “Also, the fabric has penetrations where the blower hose went in. They covered those with some kind of clear tape, but it fell off.”
Two trips to the attic with a shop vac have not solved the problem. Worse, she noticed pieces of insulation stuck in supply grilles in both the office and in the mudroom. The couple has been running the Fujitsu heat pump in the attic on its fan setting to circulate air but to date the ERV has been enough to control both humidity and temperature in the house.
Jeasto has three questions:
- Should she be worried about fiberglass dust?
- Is fiberglass dust being sucked into the HVAC system and distributed throughout the house?
- Should the contractor have done something more to contain dust from the insulation?
“I’m having trouble finding anything online because my understanding is…
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