Verdi Rice Strawbale New Home
or focus during construction or remodel:
The structure sits on a nine-acre
parcel adjacent to Toyiabe National Forest. The owner decided to construct an upscale
residence rather than a funky alternative home. Owing to circumstances, a guesthouse
(and future garage) was constructed first, and plans to eventually build the main
residence were left for a later date.
Because of the steep incline
of the property, the owner needed to build into the hillside, so the original all
straw-bale structure turned into a conventional concrete structure on the ground
floor and a straw-bale on the 2nd story.
The partial underground ground
floor really reduces the summertime west facing heat load and owner reports that
during the hottest days of the summer, the first floor maintains a comfortable
environment without any external cooling loads.
Structure features conventional
construction on first level, and straw-bale construction on the second floor.
The first floor consisted of
a dining room/kitchen and living room space part of which would eventually become
a two-car garage. A portion would be walled off and become a small kitchen, which
could serve as a possible future guesthouse, apartment, or other use.
Upstairs is the living space,
which the owner uses as a home office and master bedroom. It is entirely straw-bale
construction with two-foot thick straw-bale walls, with window seats placed under
The building is designed in such
a way that when the future house is constructed, the existing building will serve
to block traffic noise and the view of interstate 80.
& Renewable Energy Measures Used in Project (LEED Cat III):
The home was designed with south-facing
windows to take advantage of the winter sun; overhangs provide shade from the hot
summer sun. The lower floor is concrete for added mass that will retain winter heat.
The two-foot thick rice straw-bale
walls have an effective insulation value of R-53 while remaining breathable with
a lime plaster exterior skin.
The metal roof was designed for
energy efficiency with R-42 blown-in fiberglass as insulation.
The three kilowatt Photovoltaic
(PV) system with a sunny boy 2500 inverter has resulted in very low utility bills;
The only exception to this has been one instance in winter when heat tapes were
used to thaw iced gutters.
Water Heating Systems:
The concrete floors are equipped
with hydronic radiant heating—hot water is generated by a roof mounted sun-earth
solar hydronic system with four 4x10 panels, with a Takagi back up on-demand propane
powered boiler. A Goldline Electronic system regulates the Takagi and the Sun Earth
system. Since May 1, all hot water required by the household (for showers, washing
and laundry) has been 100% supplied by the solar hot water system.
The roof overhangs achieve
& Green Measures Implemented in Project (LEED Cat IV):
The rice straw utilized for the
straw bale construction is a 100% reclaimed material from the production of a healthy,
sustainable crop. This straw, brought in from northern California, would otherwise
be burned, causing air pollution. Plastered rice straw is also highly resistant
to pests, mold and earthquake damage. Lime plaster was used as a component of the
interior and exterior surfaces.
Considerations Used in Project (LEED Cat V):
The upstairs ceilings are made
of bamboo, and the steps are made from cork with brushed aluminum risers. The indoor
plaster has a pleasing old world look to it.
Considerations: How well has the structure achieved its design goals? What would be done differently the next time?
If the owner could approach this
project again, he would not choose to build on such a rocky, challenging site. He
would, however, utilize straw-bale construction.
He recommends thorough research
to find the right builder; he was very happy with his choice, Stewart Construction
from Reno, Nevada. Although the builder had experience solely with conventional
building, he had the inherent skill-set and interest to effectively push his limits
and take on the straw-bale construction of this house.
The owner was also very happy
with his architect, Josh Moore of Red Company (www.redcodesign.com) of Berkeley,
California. He felt that Josh went out of his way to insure a well designed and
Another recommendation is Roger
Roepke of Blackrock Engineering in Reno, Nevada. The owner recommends him highly
as very responsive, practical, easy to follow, and extremely knowledgeable.