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What’s the proper wall assembly for dense packed cellulose?

bRwJnaiWF2 | Posted in General Questions on

I am remodeling an older house in western New York with 2×4 framing and ¾” rough cut lumber for sheathing. The small amount of insulation in the wall cavity has fallen and sagged over time. I am contemplating pulling the old insulation out and blowing in dense packed cellulose insulation. I have also been told I should add house wrap, maybe xps rigid foam (replacement windows only stick out 1 ¼” past the sheathing though), and perhaps some kind of rain screen. However, I am really not sure what the best wall assembly would be in this situation. I have read online that the dense packed cellulose needs to be able to dry out and that house wrap can trap moisture in the wall cavity. My interior walls consist of some sort of wall board and plaster. In addition, I would like to reside the house with fiber cement siding. I would greatly appreciate ANY ADVICE on a proper wall assembly for my situation.

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  1. GBA Editor
    Martin Holladay | | #1

    You need to install a water-resistive barrier (WRB) on top of your sheathing. This can be asphalt felt or housewrap. Housewrap will not trap moisture in your wall, since housewrap is vapor-permeable.

    There are a wide number of insulation products available to improve the thermal performance of your walls. I suggest you do more online research and narrow the focus of your question.

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