Page 25 - October 2015 Green Builder Magazine
P. 25
Earth Friendly. The Norseman Great Western motel,
which features a timber frame and rammed earth
walls, is located in Western Australia, where the
building technique is fairly common.
IMAGE CREDIT: TAMSIN SLATER
successful careers. THE HUMAN FACTOR
Architect Greg Madeen has specialized in so-called “alternative”
The availability of skilled local labor has a huge impact on cost. In
building materials from the start of his career; in fact, he made Western Australia, for example, where it is much more common
the strategic decision to become a licensed architect so that he and accepted as a “legitimate” building method, rammed earth
would have more clout when doing what he calls “environmental construction is more affordable. Part of this can be attributed to
projects.” He has designed structures with sundried adobe, rammed the Aussie character, says Easton. “They see themselves as rugged
earth, pumice-crete, straw bale and other natural materials, as well and independent.” Masonry construction is also more common
as SIPs and aerated autoclaved concrete (ACC) blocks. there, so the leap from brick to rammed earth is not as great as
going from stick-frame construction.
His choice of materials is informed by the clients, the site
and what’s available locally. For example, pumice, a lightweight In the States, there are pockets where different natural building
volcanic aggregate, is abundant in parts of northern New Mexico, systems are more common, particularly in the Southwest. Madeen
and some regional concrete batch plants are willing to substitute has spent decades building a network of suppliers and craftspeople
the material for the usual heavy aggregates. The resulting material, in Colorado and New Mexico. Some are even willing to travel from
called pumice-crete, contains less cement and exhibits a balance job to job and camp on jobsites.
of insulating and thermal mass properties, and the pebbly texture
can be stuccoed or plastered without adding wire. “The Dingler cabin [see Case Study] came in at a little less than
a comparable custom home in the same neighborhood, in part
“It’s a lot of things at once,” says Madeen. “It’s a cost-effective because the crew was so efficient,” he says.
system if there’s pumice available.”
If codes are any indication, the tide may be turning when it
Madeen is motivated to develop methods which drive down comes to larger acceptance for some natural building methods. In
the cost, potentially making the technology more attractive and late 2013, the International Code Council (ICC) approved two new
accessible to more people. One of these techniques employs appendixes: one for straw bale construction (Appendix S, http://
conventional 2 x 4 or 2 x 6 wood-framed walls, but instead of bit.ly/1iSiq37) and one for light straw-clay construction (Appendix
infilling them with insulation and covering with drywall, he fills the R, http://bit.ly/1PTR4om). These appendixes are included in the
cavities with cob, which is a mixture of sand, straw, clay and water. 2015 Residential Code for one- and two-family dwellings. They
Among the benefits of “Mud Stud” walls, as Madeen calls them, include both prescriptive and performance-based requirements;
they are fire- and soundproof and have much greater thermal mass. however, methods not covered here can still be approved through
the “Alternative materials, designs and methods” section of the IRC.
“I’m pushing this as a way to reduce costs,” says Madeen. “But The bottom line? The code streamlines the path to approval, and
if you talk about anything besides painted drywall, most builders psychologically, it legitimizes the methods.
think you’re crazy.” 
