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cape cod sloped ceiling

N_G | Posted in General Questions on

I am in the process of improving insulation / venting of my cape cod. I was wondering if anyone knows from their experiences what would be the minimum R-value needed in the sloped ceiling section above the knee wall attic to prevent ice dams?
Did anyone have any success with R20, R25 or R30? There will be a properly sealed air channel between insulation and roof sheathing. My climate zone is 5 and this section of house is south facing. Thank you very much.

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  1. user-2310254 | | #1


    Check out this article (, and the links in the sidebar. I've read many posts about the challenges of insulating a cape. Spray foam seems to be the most practical solution for addressing air sealing and insulation.

  2. N_G | | #2

    Steve, thank you very much for getting back to me and for sharing the link.

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