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I have a 4-year-old home I built myself.

rcxfUnAxp6 | Posted in General Questions on

I used blown-in fiberglass up top. I went up the the attic to look lately and found that it has settled about 4 inches. I would like to use some cellulose to blow in on top of the old insulation.
Yes or no? Please help.
Fiberglass or cellulose?

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Replies

  1. Riversong | | #1

    Absolutely. Cellulose is far better insulation than fiberglass, but all loose blown fibrous insulations will settle. Blown insulations are required to have stated R-values for their settled densities.

    Cellulose will do a better job of stopping convective heat loss through the ceiling, but be sure not to block soffit vents if they exist. Vent baffles may be required to maintain a venting channel.

  2. GBA Editor
    Martin Holladay | | #2

    Ryan,
    1. Either product will work. If it were my own house, I'd choose cellulose.

    2. Remember, more insulation is better than less. As long as you're installing more insulation, you might as well install as much as you can afford.

  3. Expert Member
    Michael Maines | | #3

    Ryan, before you add more insulation you should take the opportunity to dig around and seal up any air leaks in your attic floor. Anywhere wires penetrate and around chimneys are the worse offenders. Then you can be assured that the additional insulation you add is working to its potential.

  4. Doug McEvers | | #4

    Michael Maines has it right, make sure you airseal the attic first, now is the opportunity. Sealing those attic bypasses will keep the stack effect in check and will make the lower levels far more comfortable.

  5. rcxfUnAxp6 | | #5

    thanks for the info also i am starting to finish my basement am looking at a product called insul fast trhat is glued rite on the concrete walls anyone used this product or any opion on it ?

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