To crawlspace or not to crawlspace?
We are a group of four builders in Quebec breaking ground on a new construction this summer. We’ve been arguing over the niggly details for three years as we try to cobble together the most common sense, super-efficient, affordable house possible. As we seem to be proving, the discussions on how to build can go on forever…
SOGvsFPSF… We are not keen on concrete floors for a lot of reasons. Being in the renovation business makes you realize just how terrific it is to have a certain amount of future flexibility in the design. We’d like our house to last a good, long time but have pulled out enough bathrooms and kitchens to know just because we think it’s the bees knees doesn’t mean the next occupant won’t want to rip it all out for something brand new. We don’t like standing on concrete floors and even less breaking them to move plumbing. The environmental impact isn’t pretty.The thermal mass and in-floor heat are plusses but the level of insulation and detailing we’re looking for ought to provide a nice toasty floor without it.
We’re therefore looking at having a crawlspace (unvented, well-insulated, conditioned, vapour-sealed and properly drained) with a 4′ FPSF wall with vertical & skirt insulation to allow access from below. We don’t want a basement — again because we spend so much of our time seeing them go very wrong. Ideally the stem wall would continue at the very least a foot above grade but the interior floor would be as close to grade as we can. We are thinking of framing a notch into the concrete for hanging the joists and for door openings.
Is there a clever way of having a very well insulated close-to-grade floor with some rodent protection that we don’t know about?
Any input would be most welcome. We have read both GBA’s articles on the subject of crawlspaces and know they are unpopular because they fail. We’re looking for options. Thanks!
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