 |
 |
 |
 |
 |
 |
Using natural
and local materials encourages a very different way of building. These
materials often have an inherent beauty that stands out without the need
for complex forms and shapes. Lacking uniformity, rigidity, and angularity,
they naturally lend themselves to soft, organic curves. They resonate
with the textures and colors of their natural context, reminding us that
the building belongs where it is placed. The walls surrounding us day
in and day out need to embrace us, our dreams and passions woven into
their very fabric. — from "The Beauty of Straw Bale
Homes" by Athena and Bill Steen, 2000
The modern revival of straw bale construction is a result of the growing number of people who want a home that is energy efficient, uses a renewable resource that is grown annually, and constructed of natural, non-toxic materials. More than that, many homeowners are looking for something that's harder to quantify: a house that feels like home. And not just the kind of hominess that colorful pillows, throw rugs, and a pot of brewing tea might add.
CC student Max Harper '04 believes that building and living in a house built of natural materials gives one an instinctive sense of belonging. "There's an incredible power that comes from understanding your house on a simple level - knowing and believing in the materials that you live and sleep within."
Harper, a senior majoring in environmental science, is no stranger to straw bale. In his sophomore year, Harper helped construct a straw bale pavilion in Armstrong Quad for Earth Week to educate people about green building techniques. During his junior year, Harper took an ecological design course at CC taught by chemistry professor Sally Meyer and visiting professor Dan Chiras, author of "The Natural House," in which he learned more about the viability of straw bale construction. And Harper has been instrumental in the development of CC's sustainable living theme house, Synergy, where he and other students hope to build a straw bale greenhouse.
"When you spend time in a straw bale house, you get a wonderful sense of serenity and peacefulness, but also a feeling of unexplained energy that I think comes from its being an extension of the earth," Harper said.
There are several methods of building with straw bales. The two most popular techniques are post-and-beam in-fill, in which the home's structure and roof support are provided by a skeleton of vertical posts and horizontal beams; and load-bearing or Nebraska-style, in which the stacked bales support the load of the roof. In both techniques, the bales are placed on a foundation and skewered on rebar pins, then sealed with a protective coating like stucco.
The thick bale walls have excellent insulating properties, keeping the house comfortable with a minimum of effort year-round. Jane Dillard's home has no air conditioning and even in last summer's grueling heat she only turned on her ceiling fan three times. A 23-inch thick straw bale has an R-value of around 50, while a conventional wood-frame wall using 2x6 studs and batt insulation is around R-20. According to Chiras, an efficiently constructed straw bale home can save homeowners approximately 50 to 75 percent on heating and cooling costs, compared to a conventional house. Straw bale homes achieve peak efficiency when they are constructed using passive solar design techniques, like proper site orientation, window placement, and thermal mass to absorb the sun's heat.
"Of all the alternative building techniques, straw
bale has the widest potential application in nearly any area because it
is easily adapted for different climates. But it is especially suited
for semi-arid areas with cold winters and warm summers like southern Colorado,"
Chiras said.
Chiras, who lives in Evergreen, Colo. in an "off-the grid" home he built using straw bales, rammed earth, and recycled tires, will be teaching a sustainable design course at CC again this summer.