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What about the crawlspace?

A new 1430 sf 3 bedroom 2 bath house will be built in a cold northern climate as a vacation home.  With a rectangular footprint of 25x36 feet, it will be atop a 4-foot deep crawlspace, and the mechanicals will be in that crawlspace.

Proposed heat system will be a small mod-con wall hung unit, supplying an array of panel radiators throughout.  The main floor directly above the crawlspace will have a pair of PEX loops, supply and return, with legs up to the mainfloor rads above.

That crawlspace is essentially one large short "room," well-insulated due to the foundation being of ICF blocks (5 inches total EPS foam) and the rimjoist above it being sprayfoamed.

With the boiler, its control board, a pair of shorty 38g electric DHW tanks, the blue and red loops around the perimeter, what else is needed to condition this sealed crawlspace?


  • EricAune
    EricAune Member Posts: 432

    The boiler system will most likely condition the space as is.  Proper sill insulation is a must as this is an area where infiltration can cause major energy consumption.  
    "If you don't like change, your going to like irrelevance even less"
  • Chris S
    Chris S Member Posts: 177

    I would be concerned about humidity.   ICFs & a sprayed rim joist will make for a very tight seal.  I assume you are not going to put in  foundation vents & undo all of that.  An HRV would be the next piece of the puzzle.  It would take care of  any moisture coming up out if the ground.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    Vapor barrier is a MUST

    on the floor of the crawler, otherwise it will be an issue.

    Controlling the moisture is key, and moisture, like heat, pressure and al other things that Mother Nature creates, flows from high to low. Remember, she despise differences in temperature, pressure, and humidity, and it is our job to control ALL of these issues in order to create comfort.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
This discussion has been closed.