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Crawl space insulation

boggy17 | Posted in General Questions on

I have a large crawl space the length of my home with a concrete floor and block foundation. The crawl space tends to get water in it which appears to mostly come from condensation against one of the outside walls of the foundation. The only insulation in the crawl space is on some of the hot water baseboard pipes. There are no vents in the foundation and both entry points into the crawl space are properly sealed. 

My first floor, all hardwood flooring, is extremely cold. We’ve replaced all the windows and doors and properly sealed the home shortly after moving in so it appears the crawl space is the main culprit. The only other issue appears to be a pretty large draft coming from under my sink cabinet and dish washer. 

My main question is, based on the design of the crawl space, what type of insulation techniques should I be considering? Spray in all the joists, spray only around the edges/seals? Fiberglass in the joists?

Planning on doing this in the spring/summer time. Please help!

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  1. GBA Editor
    Brian Pontolilo | | #1

    Hi Boggy17.

    With no vents and no insulation, I wonder what the intention for this crawlspace was, though it really doesn't matter.

    If you are sure that the water is the result of condensation, and if you are not in an area prone to flooding, you can probably proceed to transform your crawlspace into a sealed, or unvented crawlspace which should help with both the condensation and comfort issues. This should be helpful: Building an Unvented Crawlspace.

    If you cannot rule out a leaky crawlspace wall, you should investigate and deal with the water issue before remodeling the space.

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