Sustainable architecture may appear a modern concept, but home design interwoven harmoniously with a location's climate is a cross-cultural consciousness that spans generations. Thick adobe walls control interior temperature by trapping daytime heat in the medium, transferring it indoors during cool desert nights. Snow serves as an excellent insulator for igloos where sleeping areas up high benefit from rising warm air. In tropical climates, thatched roofing keeps structures cool during the day and the correct roof pitch helps rain run off before soaking the material. And high on a hill on O'ahu's southeast shore, the home of sustainable architect Gerald Choi breathes an environmentally friendly existence where design and nature are fused together.
It's noon on a sunny Hawaiian day, and Choi's home is as a cool haven from the 85-degree weather outside, not because of air conditioning, but to the design choices he's made. Choi is known for bringing energy efficient homes and sustainable architecture design to the islands long before sustainability was a catch phrase as common as reusable shopping bags. A graduate of the University of Hawai'i's School of Environmental Design, Choi's designed a career, and a lot of homes, by going green.
"Back then, the terms 'green' and 'sustainable' weren't used," recalls O'ahu born Choi, exuding the confident air of a composed businessman balanced with a relaxed warmth that could only be cultivated in the islands. "The [environment design] program focused on home design that took into consideration a place's climate and weather for the design."
Raised nearby in what Choi calls "Hawai'i Kai before it was Hawai'i Kai," on a family-run carnation farm with pigs and chickens, it's not surprising Choi successfully blended a sustainable consciousness with four degrees (one bachelor and three masters) into a career. Decades later, semi-retired Choi is founding partner in Ferraro Choi and Associates Ltd., an established Honolulu firm focused strictly on "sustainable architecture in an effort to promote energy and resource efficiency, and worker health" in their "built environments." Making a name with interior architecture, they quickly moved to a green focus. In 2002, Choi and his business partner, Joseph Ferraro, were the first two architects to gain certification from the Leadership in Energy and Environmental Design (LEED) program that acknowledges various degrees of sustainability for construction projects. They were soon honored with platinum status, the highest level of certification. "Today we are full-blown dedicated to sustainable architecture," says Choi.
When designing his family's house, he brought his work home with him, and that's a good thing. The Choi family residence is an impressive example of how far we've come from the days when off the grid homes translated to candlelit dinners and cold-water showers. The modern home blends an air of upscale elegance with environmentally friendly features, a realistic combination as the demand for sustainable building materials has brought cost down over the last few years.
Designed and constructed in 1992 with what Choi calls "fundamental sustainable design strategies" in mind, the spacious and bright home works in unison with the natural elements. From roof and wall angles to landscaping, the Aina Haina ridgeline home is about as green as can be, metaphorically speaking. White walls and light oak flooring enhance the bright environment while white was also chosen as the exterior color to reflect solar heat. Choi says the difference between a white and dark wall can be as much as 10 to 20 degrees.
Facing directly south, Choi's home gets an unbeatable ocean view and enough sunlight to brighten nearly every nook and cranny in the nearly 4,000-square foot house. To reduce heat intake, the architect followed the "two to one ratio rule," a design strategy requiring an overhang twice as long as the tinted south facing glass doors are high. "Glass tinting is an effective and affordable way to cool homes, too," Choi advises.
Insulation, Choi's version of an inexpensive option to cool homes, lines the inside of the roof and the south, east and west facing walls. Cross ventilation keeps the inside temperature down thanks to strategically placed windows and ceiling fans instead of air conditioning. Awning-style windows, which provide 100 percent ventilation when fully opened, contribute to a comfortable indoor temperature, and the refreshing breeze moving through the house proves his green-minded decisions are effective.
Although these environmentally conscious aspects have existed in the home for decades, Choi is on a never-ending search for sustainable home additions. "Going green is not a one-time strategy," he says. "I have implemented almost all of these green strategies since we built our home and I continue to this day to add new green improvements that address other issues of sustainability, such as water conservation and rainwater harvesting. It has been fun and very rewarding to make our home a part of a greener community."
Some of the latest home improvements have been in the realm of energy efficiency. In 2009, Choi made a decision he calls a "no brainer" and installed a solar hot water heater. "It reduced our electric bill by about a third, but we knew we could do better," he says. So when facing the challenge of replacing an old 45' x 5' skylight that ran along the house's axis from east to west to maximize light entering the home, Choi arrived at his latest effort to incorporate clean energy into the home's design, the installation of a photovoltaic system that would also function as a skylight.
After an exhaustive search, Choi finally found a product that could meet both his needs for an energy-producing skylight. Unlike most photovoltaic panels mounted on racks on a rooftop, Choi's photovoltaic system feature photovoltaic cells sandwiched between panes of glass. Now, he could seal out the elements, let natural sunlight into the home and create energy at the same time.
"It's really redundant to have the system lying on top of the roof like most homes with solar do. It's like killing two birds with one stone, to have the system itself serve as roofing," says Choi, pleased with the outcome and aesthetics of his custom PV system.
Installed by Hoku Solar, Choi's 3.12 kW PV system is what is also known as integrated solar, the latest in solar panel technology. Integrated solar is touted as the way architects and designers can bridge the gap between function and aesthetics.
"Mr. Choi's project is revolutionary because it demonstrates that PV can be integrated into building design in a thoughtful and tasteful manner," says Scott Paul, CEO of Hoku Corporation. "Mr. Choi's PV system is itself a piece of modern art and it shows how PV should be designed into a home from the beginning, not just installed as an afterthought, and that it can please the most discriminating taste."
After a nearly two-month installation process, Choi had clean energy running his three-bedroom, two-and-a-half bathroom home for the cost of about three lattes a month, a drastic difference from his previously standard $200 monthly bill.
While Choi has built a career on sustainable home design, he acknowledges there are obstacles, often financial, that stand in the way of homeowners' efforts to go green. "There's the upfront costs, but there's real savings in the long term," Choi explains. "We're in for the long haul, but will definitely make out better in the long run." With a $26,000 installation cost, a tax credit half that, and savings just short of $200 a month, Choi estimates he'll break even in roughly six years, possibly faster with rising electric rates. But the savings go further. Since his PV system is a grid interface system connected to the electrical grid rather than a stand-alone system relying on batteries for storage, Choi's PV-generated electricity goes back into the grid. "This actually turns my electrical meter backwards, thereby giving us credit for the amount of electricity we contribute to the grid," says Choi.
Adding to the functionality of Choi's PV system is the bi-facial panel, which absorbs light on both sides. So even light reflecting into the house and back out is captured and converted into electricity.
Choi appears to be on an ongoing journey towards an environmentally friendly home. The yard is landscaped with plants living in their natural windward and leeward habitats. On the north side of the yard are bigger trees that naturally block wind and rain. And they shade the ground, minimizing evaporation and lessening the need for frequent watering. In the front, or the leeward side of the yard overlooking the ocean, Choi is currently in the process of installing a drought tolerant garden. The foliage he's planting is found naturally in the area and is on the shorter side, reducing the need for pruning to maintain the view.
Standing on Choi's roof, the PV system glistening in the sun, the occasional standard solar panels dotting distant rooftops are a reminder of Hawai'i's goal for a sustainable future. Not surprisingly, the environmental conscious architect is optimistic for the islands. "As time goes on, especially in the U.S., green sustainable design is becoming the norm," he reflects. "Consequently, much of the public now almost expects one to be knowledgeable in sustainable architecture, which will eventually phase out designers and builders that are not knowledgeable in sustainable architecture."
Professionally speaking, Choi says he always tried to steer people in a green direction and acknowledges there's a lot people can do on the personal level with small, yet significant choices. He says, "If one can first develop a green outlook on the way we live, there are many inexpensive investments and green practices that one can do to improve their home to become more sustainable. By adopting a green mindset, one can start with small gradual steps in behavior and green investments to make their home a more sustainable, more comfortable, and more affordable place to live."