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Fiberglass vs cellulose

Can someone please tell which one is better and why?
I want to put more insulation in my attic and am debating between fiberglass and cellulose. Some people said fiberglass is better while others said cellulose; I am very confused!
I live in Denver Colorado.


Re: Fiberglass vs cellulose

I prefer fiberglass properly installed with bats between the joists and another layer running across the joists. Cellulose, while it does do a great job filling voids, settles over time. You can blow in 6" of cellulose and in just a few years it settles and you end up with about ½" plus it's a nightmare if you ever get a roof leak. By far the best choice would be closed cell foam. It has a greater R value per inch, fills all voids, seals along joists, and is almost structural.

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