Modern Updates to Old-School Building Materials
09 October 2013
In modern times, old ways of building from nearby materials have fallen into disuse, succeeded by new manufacturing techniques preferring two-by-fours, concrete, and steel. Now a form of construction known as “natural building” has attracted followers, as people realize that some housing traditions may be worth reprising — in large part because of the energy savings they can yield.
Homes built with natural materials like straw, sand, earth and rock can conserve energy by cutting down on pollution generated by producing and transporting manufactured materials, as well as significantly reducing overall energy costs and consumption. Labor costs and concerns raised by city officials and inspectors can hinder construction, but processes using straw bales and rammed earth, a material similar to adobe, are making progress.
Rammed earth walls are made of subsoils (which lack the organic content of topsoil) on or near the housing site, combined with a small percentage of cement added to the mix to meet building codes. Rammed earth has a lower insulation efficiency, or R-value, than fiberglass, but it takes a long time for the outside temperature to make its way inside. The material is “tremendous at storing thermal energy,” said David Easton, a builder and founder of Rammed Earth Works, based in Napa, Calif. In other words, it takes a long time for the outside temperature to make its way inside. Houses made of rammed earth allow cooler temperatures at night to keep the house comfortable during the day.
Juliet Hsu (B.A. Architecture '04), a 34-year-old architect, has radiant heat floors but no air-conditioning in the rammed earth house she designed for herself and her husband, Jack Menzel, in Mountain View, CA. The 2,200-square-foot house, where they have lived for two years, cost $500,000 to build; the builder, Mr. Easton, is Mr. Menzel’s stepfather.
Mr. Torcasso and Ms. Hsu said that living in a rammed earth home is aesthetically appealing.
The striation created by the layers of soil creates “beautiful lines,” Ms. Hsu said.
Image: Eric Draper/NY Times