Vermiculite insulation
Riley Leppo
| Posted in Energy Efficiency and Durability on
Hi, I have two or three inches of vermiculite insulation in my attic. I have already read up on all the hazards and removal options. I don’t use my attic for storage or any other reason to enter. I don’t feel the vermiculite is adequate insulation and want to reinsulate. Can l blow 6 to 7 inches of insulation of the top of it? I was thinking of using the block insulation you buy from Home Depot.
Thank you for the help!
Riley
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Replies
Air sealing is the first prerequisite to adding more insulation. Unless you KNOW the vermiculite is asbestos free, the air sealing process may have some hazard for the air-sealing worker and the occupants.
What is "...block insulation..."?
The problem with blowing on top (I assume you mean cellulose) is that you are missing an important opportunity to air-seal the attic floor, which is a mistake in my opinion. I would get a legitimate company to remove the vermiculite and start with a clean slate.
Riley,
Blowing insulation on top of the existing vermiculite could endanger your health and the health of your family. Don't do it.
Here is a link to a GBA article with more information: Fixing Attics With Vermiculite Insulation.