Floor system for helical piling construction
We are building a net zero home in northern BC, the temperature here can dip to – 40. We have decided to use a helical pile foundation using beams, supporting engineered joists for the floor. The crawl space will not be heated. I am looking for some advice on how to insulate and seal the floor. Any help would be greatly appreciated. Thanks
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I'd start with this article:
I did something similar in my house. I found it really, really hard to get the trades to understand that it was an unheated crawlspace with an insulated floor. Every time I turned around the plumber was trying to run a water pipe through it or the HVAC guy was wanting to run ductwork in it -- even though I had given them drawings showing where things were supposed to go. I had to get the insulation guy to come back five times before it was insulated the way it was supposed to be.
Great article, thanks!
You may find these discussions useful too: https://www.greenbuildingadvisor.com/article/the-best-way-to-insulate-a-floor
One other point perhaps not mentioned in the articles: Enclosing a crawlspace with a skirt is tricky for a few reasons:
- Building codes don't draw the distinction between a conventional crawlspace and a house on piers with a skirt. Once the underside of a house is enclosed, it's a crawlspace, with all the requirements that brings.
- You will need an insulated core to bring services up into the house without freezing. You may want to use something the detail shown in this link: https://www.southmountain.com/wp-content/uploads/2019/02/19-Small-Home-Harmony-Article-PDF.pdf
- Pests find it a lot easier to access the area. Make sure whatever protection you use on the underside of the floor system can keep them out.
Here's another link: "Crawl Spaces vs. Skirts"