Cellulose for new walls – wet sprayed or dense packed?
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I would like to install cellulose as the main wall insulation inside 2×6 framing. There will also be 2 inches of rigid board insulation outboard. Climate zone is 6.
What is the latest know how on the relative merits of wet sprayed v.s. dense packed cellulose for stud walls? Can the dense packed be installed so it does not sag / sink down at the top over time?
Thank you!
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Replies
Hi Matthew.
I'm not aware of an appreciable difference in performance of properly installed wet spray and dense pack cellulose. Neither should have voids or settling or moisture issues if installed by an experienced installer. So, the key is to find a good contractor. Check out this article for more info: How to Install Cellulose Insulation
>"Neither should have voids or settling or moisture issues if installed by an experienced installer."
Neither SHOULD have voids, but the track record on damp sprayed isn't all that great, with shrinkage separation away from the framing if the initial moisture content is too high.
Take a look at the photos Armando Cobo posted in response to this thread:
https://www.greenbuildingadvisor.com/question/how-much-for-damp-spray-cellulose
You can't exactly toss a cat through that gap, but there's plenty of daylight:
https://s3.amazonaws.com/greenbuildingadvisor.s3.tauntoncloud.com/app/uploads/2018/08/08102458/Wet%20Cellulose%20and%20Stud%201-700x934.jpg