I just finished Danielle's article on the Walipini. My first impression was "How similar to Passive Annual Heat Storage" homes. Both use soil mass and passive solar gain. The difference is that PAHS uses an insulated umbrella to protect the soil mass from heat loss (or gain). PAHS generally wants 20 feet in all directions laterally from the structure to have the umbrella (as well as any above ground structure). This allows the waterproofed, insulated soil to normalize at a higher temperature than the local temperature.

There are some PAHS references on the web, examples of homes that have been built and the 1983 book by John Hait is available in e-form from Amazon (if you are really interested). Build It Solar is also another web site that has some other solar green house ideas. The rain barrels might also provide heat storage in the winter as well as tempering the heat of summer.

I will probably not be building a Walipini, but we do plan on a PAHS house in the next 2 years.

For structural input on the design that Danielle used, the tall retaining wall on the south side is somewhat supported by the shorter wall under her beds. This design is elegant in that vertical earth faces tend from the bottom of the excavation on a diagonal line or a shallow concave. The base for the walkway appears to be 4 by 4 or 6 by 6 timbers, resulting in a brace that gives great support to the base of the taller slope. The narrow walkway and the size of the timbers keeps the timbers from bowing.

A great article. I look forward to seeing more about Danielle's Wapipini.


Neal in Iowa