Private Residence, Joshua Tree, Calif.
Mary Estes ,
Posted
10/28/2011
When designing a home in the Mojave Desert, blistering sun and
gusting winds top the list of challenges. Shade and sustainable
design come at a premium, and creating it inexpensively is no easy
task.
Faced with the challenge, Los Angeles-based architect Walter
Scott Perry, AIA, found an answer in a lightweight perforated
aluminum panel. Perry's firm, Ecotechdesign, and 44 West
Construction Inc., Topanga, Calif., completed the project in early
2011. The custom-built, 2,400-square-foot home includes the owner's
private photography studio.
The unique part is the object used as the core building
material-ISO corrugated metal cargo shipping containers, which he
partially wrapped in the perforated metal panels from Tampa, Fla.-
based McNICHOLS Co. The panels serve as an exoskeleton and sunshade
to control heat. Because they diffuse light, the metal panels
reduce solar and wind impact by 50 percent.
Purchased from a Long Beach, Calif., dock, the six cargo
containers were converted off site into modular units complete with
windows, plumbing fixtures, wiring, kitchen and finishes, ready for
onsite hook up. Transported four hours on a flatbed truck, the
containers were installed in 15 minutes each, and covered with the
perforated metal panels using a system Perry calls a
"kit-of-parts."
Besides complementing the modern look of his container design,
the metal panels, like the containers, were easy to transport and
handle, says Perry. "And the installation requires only simple
everyday construction tools."
Natural Ventilation
Perry used McNICHOLS Designer Perforated Aluminum Metal with
3/16-inch round holes on a 1/4-inch staggered pattern in 16-gauge,
which was cut into 4- by 8-foot and 4- by 4-foot panels. The
material covers 1,800 square feet over the two roofs and the south
and west facing exterior walls of the living quarters.
Each panel was secured with stainless steel bolts and washers
onto Unistrut T1001, 12-gauge galvanized steel framing members
bolted together on 4-foot centers. The framing sits 8 inches off
the exterior wall and 4 to 6 inches above the roof. Unistrut
framing is by Atkore International Inc., Harvey, Ill.
"The idea was to create a home that is passively cooled using
natural ventilation," says Perry. "The extra 8-inch space between
the skin and the exterior wall allows air to circulate around the
home, create more efficient cooling, as well as facilitate cleaning
and maintenance."
"Another advantage of the perforated metal is its partial
transparency which changes during the day, based on the suns
relative position," he says. "During the late afternoon, it becomes
more reflective due to the lower sun angle, thereby reducing glare.
In the morning, it's more transparent from the inside, thereby
enhancing the views out over the desert landscape"
The residence sits on a 2.5-acre rural lot in Joshua Tree,
Calif., at the foot of Shadow Mountain, roughly 40 miles east of
Palm Springs. The 900 square feet of living area consists of five
cargo containers, two placed on top of three to create two levels
that include the kitchen, living room and half bath on the first
floor and bedroom and full bath on the second floor.
The stairwell is a U-shaped structure covered with corrugated
metal siding, complementing the steel wall panels of the
photography studio to the west, which is a 21-foot-high
pre-engineered steel building from Butler Manufacturing, Kansas
City, Mo. The sixth cargo container literally plugged into the
studio where it is used for equipment and material storage.
Installation Made Easy
Perry said the planning team first intended to use the
perforated aluminum as a shade canopy to create the 500-square-foot
outdoor living space for people to gather and socialize without
being subjected to excessive heat and wind. The idea quickly
evolved into creating an exoskeleton covering the two roofs and the
south and west exterior walls, an approach that proved economically
and environmentally beneficial.
The system accommodates the photovoltaic, hot water solar panels
and green roof modules that are bolted directly through the
perforated metal onto the Unistrut sub-framing. Perry says he was
able to install the exoskeleton system, including sub-framing,
metal panels and labor, at a cost of $10 to $12 per square foot.
According to Eric Engheben, owner of 44 West Construction, the
completed home was built for $150 per square foot.
The cargo containers, which measure 20 feet long by 8 feet wide
by 8 1/2 feet high, were cut and opened up in strategic locations
to conform to Perry's open floor plan.
"It was a true collaboration between builder and architect,
which is the main ingredient for a successful project," says
Engheben. "Using the perforated metal, for example, changed the
whole appearance of the structure. Not only does it add an
architectural element, it helps prevent heat gain."
With the container units painted a highly reflective cool white
on the sides to match the "cool roof" with an SRI=0.75, and
combined with the metal shade canopy and other energy saving
features, the construction exceeds California's Title 24 energy
requirements for code approval, says Perry. The container wall and
roof insulation systems exceed code by 50 percent.
Other energy saving features include a roof membrane of
single-ply TPO, a 10,000-gallon water storage tank, 3,000-gallon
cistern, water harvesting and grey water system, and interior walls
of plywood from a sustainable source monitored by the Forestry
Stewardship Council.
In addition, natural daylight and ventilation are used
throughout the containers with large operable windows and sliding
glass doors; the photo studio uses dimmable Velux Sun Tunnels from
Greenwood, S.C.-based VELUX America Inc., to control daylight
levels and heat buildup throughout the day. The home has a
mini-split heat pump system for air conditioning and heating with a
17 SEER rating.
The perforated metal skin makes this home architecturally
unique, says Perry, as it integrates the various hybrid building
components, creating a sophisticated and contemporary industrial
aesthetic. While the perforation already decreases the home's solar
exposure by 50 percent, Perry says he is considering adding
different panel opacities on the roof, which could achieve up to 90
percent shading, while still allowing for drainage and
ventilation.
Mary Estes is principal of Estes and Co.,
Tampa.
Private Residence, Joshua Tree,
Calif.
General contractor: 44 West Construction Inc., Topanga,
Calif.
Architect: Ecotechdesign, Los Angeles
Perforated metal panels: McNICHOLS Co., Tampa, Fla., www.mcnichols.com
Metal framing system: Atkore International Inc., Harvey,
Ill., www.unitstrut.us,
Metal building: Butler Manufacturing, Kansas City, Mo.,
www.butlermfg.com,
Skylight: VELUX America Inc., Greenwood, S.C.,
www.veluxusa.com