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Shell insulation

user-4221191 | Posted in Energy Efficiency and Durability on

Having researched this sight for all related information on a new house in the mountains of the southwest in region 5, I have a few unresolved questions.
My goal is to have R-60 floor and roof and R-40 walls. I’ll do the walls out of double 2 X 4 walls with dense packed cellulose. The exterior will be fire resistant Hardiplank or equivalent. Roof will be raised heel trusses with dense packed cellulose. The heels will be two foot. I’ll have a OSB deck covered with standing seam metal roof. I plan on doing a rubber torch down roof base. Do I need to address moisture in some additional way? My floor will be I-beams supported on block stem wall. What is the most efficient method to insulate the floor structure?
This site has amazing information and insight.

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  1. wjrobinson | | #1

    Is there a builder?
    Is there an architect?
    Plan source?
    Do you need building permits?
    Do you know your building code requirements for your location?

    After you learn here what you want, who is implementing the information and doing the plans and doing the work?

    Go to this site, read lots and buy some books,they are very helpful.

    Join this site and look into all the specific detail sheets your plan needs. GBA

    I am not a fan of OSB or I-joists made with OSB. Solid timber homes have a longer life and also last longer in a fire, and timber frames longer than that and stone longer still. I stick with solid wood myself as I am not a stone home builder.

    Zip sheathing is a better OSB product along with Advantech. I use both and also high grade plywood. I will use standard OSB though I do not like to for wall sheathing, but really try not to use it for roofs.

  2. GBA Editor
    Martin Holladay | | #2

    R. Ferd,
    You describe your foundation walls as "block stem walls." Although you didn't explain what you meant, this sounds like a crawl space foundation. It's also possible that you plan to build a full basement; I'm not sure.

    Whether you are planning a crawl space or a basement, I think that it makes more sense to insulate the crawl space walls (or the basement walls) rather than the floor assembly above the crawl space or basement. For more information on this topic, see:

    Building an Unvented Crawl Space

    How to Insulate a Basement Wall

    One last comment: I think it makes sense to upgrade from CMU foundation walls to poured concrete foundation walls. You'll never regret the decision.

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