People hear the word sustainability and green building tossed around a lot these days. But what is sustainability? It can mean different things and is often over-used. Hofmann has made sustainability more than a motto, or worse a sales pitch, “It’s designing something for life.”
Another way Hofmann looks at is, “creating with the capacity to endure.”
According to the U.S. Department of Energy, buildings use 39% of the energy and 74% of the electricity produced each year in the United States. The buildings we create are by far the greatest single consumer of energy and natural resources in the United States today. “The intention of sustainable design,” says Hofmann, “is to eliminate the negative environmental and human impact by being sensitive to your actions and the impacts they have on our world.”
So what were the steps to creating sustainable design in his home/office on wheels?
Step #1: Demo it – Remove everything – along with lots of scrubbing to eliminate the wet dog smell.
Step #2: Design it – The creative process, Hofmann believes, isn’t accomplished by adding more, but by taking away what’s distracting. The design questions were simply: How much does one remove? How much does one keep? Perfection isn’t when there is nothing more to be added, perfection is when nothing left can be taken away.
Step #3: Live It – There is a must-do list that must include the use of regional materials and reusable products, such as bamboo for flooring, countertops, the table, along with a sustainable management plan. Weight was also a huge issue. Less was more. Lighter was better. And like luggage packed on an airplane, the load needed to be properly balanced.
Here’s how Hofmann answered the sustainability questions in the design and outcome of his 1978 Airstream renovation:
Reuse an existing structure when possible
The first most unsustainable action one can take when it comes to living is to build a new home where there was no home before. A new home takes a large amount of energy and natural resources to make. Using an empty shell (floor, walls, roof) in an existing building requires significantly less embodied energy than new construction. By eliminating the need for a foundation, new walls, windows, a new roof, etc, the potential resources that would have been required to build these elements can be transferred, or saved all together. This is not only more sustainable, but much more cost effective. There are many beautiful downtown “urban loft” style projects in many city centers that have reused very old manufacturing plants, or storage facilities, many made with brick, or concrete, and remodeling them into very successful residential dwellings. The Airstream project is, at its heart, an exercise in reusing an existing space.
Local suppliers for new materials
Sustainability calls for placing a high priority in using regional materials and suppliers. The embodied energy of a material or product is how much energy is required to get a certain product from it’s natural state (forest, earth, etc.), to final installation in one’s home. There are many factors to consider, one of which is shipping. It takes more energy (fuel, pollution, $) to get a product from China, for example, than it does to get a product supplied locally. One focus on the Airstream project was to use regional material and suppliers. An example is the bamboo flooring from a company called “Cali Bamboo” (used for all flooring and countertops, table) . This supplier is less than 100 miles away.
Natural paints and finishes
Did you know that indoor air is three times more polluted than outdoor air? According to the EPA paints and finishes are considered one of the top five hazards to human health. Paints and finishes release low level toxic emissions into the air for years after application. The source of these toxins is a varitey of volatile organic compounds (VOCs) which, until recently, were essential to the performance of the paint. New environmental regulations and consumer demand have led to the development of low-VOC and zero-VOC paints and finishes. One important, but often overlooked, aspect of sustainability is the use of paints and finishes that are made from natural raw ingredients such as water, plant oils and resins, plant dyes and essential oils. There are also many natural minerals such as clay, chalk and talcum; milk casein, natural latex, bees’ wax, earth and mineral dyes that can be used in the finishing process. Water-based natural paints give off almost no smell. The oil-based natural paints usually have a pleasant fragrance of citrus or essential oils. Allergies and sensitivities to these paints is not common. Using low- or no-VOC paints is especially important in a small area, such as a trailer. It’s safest for your health and for the environment.
Sustainably-grown materials
Natural materials that take less time to grow may be replanted and grown again. Bamboo is one of the fastest growing plants on earth and typically takes just 5 to 7 years to mature. On the other hand, hardwoods such as oak take from 20 to 50 years to mature.
Heating and cooling
The Airstream uses an integrated propane heating system on colder nights. For cooling, the Airstream uses two large awnings on each side to shade windows from direct sunlight. Large open-able, screened windows promote ample cross-ventilation to take full advantage of Southern California’s ocean breeze.
Electrical
The Airstream utilizes a low voltage battery system with integrated charger. This system supplies 12 volt lighting and fans, or converted 110v power. Batteries are recharged from the automobile while in tow, and a solar panel battery charging system is currently being installed. Low voltage lighting, such as fluorescent and halogen, are utilized throughout the trailer.
Tile
Traditional tile is installed over a concrete backer board that is heavy and rigid. But it doesn’t bend in a round-walled trailer. It’s also too heavy. Fortunately, there’s a new product available – porous flexible foam with adhesive tar applied to the back. An adhesive primer is first applied over the sub-structure (wood base of shower structure) then the foam backer is adhered and secured with screws every 6” (for vertical surfaces.) The mortar for installing the tile is applied directly over the foam. The porosity of the foam secures to the mortar and creates a homogenous attachment. A flexible grout additive is used to decrease the risks for cracking. Small tiles were chosen to minimize the cracking of individual tiles. The trailer has been in tow several times with no cracking.
Water conservation
High efficiency fixtures are used throughout. Water flow control devices are installed on every water fixture. Small hot water tank encourages short showers. Extremely low flow water closet is adaptable to the type of waste. (less water for liquid waste, more for solid waste) Two separate storage tanks: graywater and blackwater. Gray water is diverted from sewer and used for landscape irrigation. The Airstream is not hooked up to city sewer, so blackwater waste is biologically-treated on-site through a leach field/septic tank.
Working with sustainably-minded companies
Sustainably minded companies have less environmental impact and often have a program in place to donate funds or time towards environmental organizations.
Hofmann says, “The solution was creating open space using honest materials. I wanted to bring a sense of outdoors in, so it needed to be bright and airy by nature, yet warm and multi-functional.”
As a licensed architect he also needs a quiet, comfortable place to work – a space that is mobile and easily converts from residence to workspace.
Hofmann is clearly comfortable blending his home and office. “For me, a space that serves only one purpose is a waste of space. But for someone else it may not work.”
Last January, Hofmann hitched up and took his first road trip to the El Capitan Mesa RV Park that overlooks the Pacific Ocean and Channel Islands. “It took just 10 minutes to hook-up and it rolled along great,” he says. “The next morning I took a long walk on the beach, went for a swim, and later worked on a new project.”
“I enjoy working with clients who are willing to step boldly into the future with gutsy audacity,” he says. “Events such as the Tea Fire remind us that life’s too short not to overstep the boundaries of the ordinary and dream big.” Matthew Hofmann is available to speak with to answer your questions and currently looking for new thoughtful and progressive architectural clients.
Check out their website and blog at www.hofarc.com for more information.
