There are some places where getting  off the grid is an admirable aim and others where it is an absolute necessity. Great Barrier Island, a four-and-a-half-hour boat trip (or half-hour flight in  a tiny plane) northeast of Auckland, New Zealand, falls firmly into the latter category: With a permanent population of approximately 1,000 people, the  island has no municipal water or electricity supplies and no sewage treatment facilities, meaning every home there has to be self-sufficient.

Some people would be daunted by the challenge, but South African–born architects Lance and Nicola Herbst relished an opportunity to design something completely off the grid. The couple first visited New Zealand in the mid-1990s and were enchanted not only by Great Barrier Island’s isolation and spectacular white-sand beaches, but by what Lance describes as “little timber shacks we had never experienced before—–tiny buildings with 20 years’ accretion of stuff.” In New Zealand, these shacks are called “bachs” (pronounced “batches”) because they were historically designed for bachelors. Nowadays, the word  is used to describe any sort of vaca tion home, no matter how lavish.  The Herbsts, however, strive to inform their design with the implicit modesty of the term.

Three years after their first visit,  the Herbsts moved permanently to New Zealand. They purchased land on Medlands Beach, on the island’s east coast, and built a small bach there. The intimate knowledge they developed of the area put them in good stead when, in 2005, their friend Marc Lindale asked them to design his vacation home on a 9,250-square-foot site a little farther down the same beach.

Lance says the lack of services on the island meant the home’s design became “a diagram of the basic provision of shelter,” not unlike early bachs. This straightforward approach was aided by their decision to dispense with the patterns of city life in favor  of predominantly outdoor living in the island’s subtropical climate. There is no front door to the home, just a few steps up to the space that serves as its heart: a covered terrace with a large dining table, backed by a gabion wall made from local stone. Behind it is a slim two-story structure containing the home’s two bedrooms and only bathroom; reaching toward the beach is  a longer structure housing the compact kitchen, dining, and living areas. At the rear is another deck with a bench designed for filleting the day’s catch of fish for dinner. The building’s pine frame sits on a base of concrete blocks and is clad in cedar.

With no water supply, the roof was designed to collect the island’s plentiful rainfall and store it in an underground tank for drinking and washing. Another tank stores treated waste  water for irrigation of the site.

Inside, all electricity needs were assessed and edited by an electrical engineer to minimize demand on the four 150-watt solar panels installed on the roof. The Herbsts took a threefold approach to keeping the amount of power the home uses to a minimum: “Firstly, by providing targeted task lighting,” explains Lance, “Secondly, by creating a low-lit ambience, which diverts attention to the night sky; and thirdly, by necessitating the use of  candles and Coleman lanterns, which are rituals associated with camping and traditional bachs, many of which relied totally on candles for light.”

The Herbsts also disconnected the oven’s electric grill and Lindale banished the toaster after discovering  that both would require energy surges the solar panels could not deliver.  “It takes a mind-set shift for people who come from the city,” Lance says. “You need to be cognizant that every time you turn something on, the power has to come from somewhere.” Compromises had to be reached over the television and the dishwasher, two things Lindale insisted on but the Herbsts opposed. Luckily, the architects located low-energy versions of both appliances.

All in all, the home’s simplicity makes it a convincing modern rendition of the improvisational shacks the Herbsts admired when they first visited the island. The surprising thing is how this pared-down approach has made living in the home feel much more like a pleasure than a chore. “City houses have become machines for living,  and there’s