Continuing on with my last column's topic of designing a home that is compact, and therefore space-efficient, this week I will discuss sailboat design as an analogy to house design. Form and function merge in sailboats made for cruising. The craft must be able to cut through the water easily while being driven by the wind. With proper sail and hull design, the sailboat can travel for thousands of miles without fossil fuels by using a natural power source—the wind. The craft is durable, controllable, and comfortable to live aboard. As an example, a self-contained 35-foot long sailboat can provide the comforts of home with a galley/dining area, sleeping areas, bathroom with shower, storage, electrical supply (often powered by a photovoltaic system that converts sunlight into electricity), a sewage system with a holding tank, fresh water supply for sinks and showers, and storage. Every square inch is put to maximum use. The seating in the galley contains storage underneath and converts to sleeping berths at night. The area beneath the front berths has ample storage for multiple sails (the low-tech and non-polluting "engine") and other gear. The space beneath the rear deck and cockpit may contain a sleeping berth on each side along with the auxiliary engine compartment between the berths. The lighting system will always be very energy-efficient and will use fluorescent and LED lighting exclusively. Small pumps pressurize the fresh water system and can pump any water out of the bilge (the lowest part of the boat) that happens to leak in. Cabinets and storage lockers are placed in every conceivable place. A navigation table may fold out of the wall when needed. Operable ventilation hatches and windows bring in fresh air and daylight. The stove swings on a gimbal in order to keep food from spilling as the boat rolls.
The compact quarters below deck are in contrast to the rear deck that has an unobstructed view of the entire horizon. The ocean becomes your backyard. Built-in seating is ample and very durable. With a full view of the sails, the skipper can precisely adjust the angle of the sails to take maximum advantage of the wind velocity and direction, thus powering the boat.
In a strong wind, the boat heels, or leans, to one side. Even this is a wonderful design feature that may go unnoticed by the casual viewer. The keel, or the lowest part of the hull, is filled with a heavy ballast. As the boat heels to one side in a brisk wind, less sail area is exposed to the wind, thus reducing the tendency for the boat to roll over. At the same time, the keel creates a stronger righting moment, thus always striving to keep the boat upright. In other words, the sailboat is self-balancing without any input from the skipper.
What does all of this have to do with the design of a green home? Everything. A properly designed green home will incorporate this same design mentality—comfort, compactness, using nature as a power source, and self regulation.
The sailboat incorporates the comforts of home and the ability to sail indefinitely without the need for gasoline or fossil fuels. Our homes can also be comfortable and enable us to thrive for years with little or no need for utility-supplied power. Temperature swings are minimal and self-regulating, achieved by the proper use of window placement, roof overhang design, thermal mass walls, and superior insulation. Electricity is generated by the sun, and some or all of the water is supplied by the rain collected from the roof. Buildings should function like a living system—they utilize what the local environment provides and do not harm it in return.
Next week I will start talking about the construction process, including how good design decisions can help protect the environment.
[This has been a guest post by Ted Owens, a green designer and filmmaker. More details on green building design and construction can be found on his website and in the Building with Awareness DVD and Guidebook. -Ed.]