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Community and Q&A

floor insulation choices in pre-fab shed

rwickman | Posted in Energy Efficiency and Durability on

12 X 32 prefabbed shed in Western Maine, Zone 5.  I believe.  Shed is a plywood subfloor on a joist system;  held off the ground by CMU’s to level it.  This will be a 3 season living space until we are able to build a home.   I am thinking about either 1″ blue board or 1″polyiso glued to the existing floor, and then add 1/2″ CDX over that, screwed to the existing sub floor.   Bottom plate junction with insulation and plywood will be airsealed.   Cost is an issue of course.  I know I will get a higher R value with the polyiso;   Wall and ceiling insulation is TBD;  floor needs to happen first.   Thoughts, comments, appreciated 

Thanks much

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  1. user-6623302 | | #1

    Think return on investment. I don't think you will save enough heat to warrant the insulation investment. Insulation gets you the most return when the weather is cold (winter).

    1. charlie_sullivan | | #2

      I think a lot depends on what is really meant by 3-seaon. Also, what heating source.

      1. rwickman | | #3

        Early Spring to Late Fall- ; heating system is either a small wood stove, or a direct vent propane stove. With the current economic situation, this could wind up being a full time home.

  2. user-6623302 | | #4

    Year round is totally different than three season. You have the plumbing issue. I would consider building on an insulated, sealed crawlspace. Site it so that it can be incorporated into the new home, for example, as a kitchen wing.

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