David Easton, author of The Rammed Earth House and owner of Rammed Earth Works in California, shares his earth floor building method in Popular Science. Click link below for full article.
“My family and I live in a beautiful earth home with a handsome earth floor. It may sound unbelievable, but as a successful builder of rammed earth houses I’d been trying for a while to expand the use of earth to finished flooring. After much experimentation, I’ve finally found a suitable mix of soil and cement to do the job.
Why bother? Well, a soil-based floor is softer and more comfortable than a conventional concrete slab, and if you lay it yourself, it’s less expensive. As a bonus, it can be stamped to look like rustic tiling that has an earthy color. Finally, a soil-cement floor is a natural for passive solar heating and a perfect medium for hydronic radiant slab.
Soil-cement is softer underfoot because it is less dense than concrete. Unlike the aggregate used in concrete, soil expands significantly when it’s wet. As a soil-cement slab dries and the soil particles lose water, they shrink, and millions of tiny air pockets develop. These air pockets essentially make the floor a little spongy.”
[Easton goes on to explain all the steps in detail. He recommends a 1” thick layer of soil cement on top of 4” of well-compacted soil such as road base. This saves cement because only the top 1” is stabilized.]
Source: Popular Science, Dirt Cheap Dirt Floors by David Easton (type the name of the article and author in a search engine if the link doesn’t work)
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