Costa Rica’s Osa Peninsula is a green builder’s dream. Native and plentiful, guarada bamboo is an ideal building material, capable of taking a nail without splitting. In this tropical climate, walls are often unnecessary; everyone wants to be open to the moist air and the jungle’s breathing.
Markus Wehrmeister and Gabriela Naranjo have built five cabinas and seven bamboo tiki tents at Finca Exotica, a resort and permaculture farm on the shores of Carate Beach. “You can see my learning curve manifested in the cabins,” Markus told me as we toured the tiny portion of the vast swath of land that they’ve bought and put into protection. No one here seems to mind.
For Markus, an architect and former caterer who came to Costa Rica from Berlin nine years ago, bamboo was a new and sometimes mysterious material. He’s learned, over the years, that the hearty grass—as strong as our most durable hardwoods—must be harvested at the end of the dry season, five days after the full moon, at low tide and at night because that’s when is empty of sap. “To secure quality, the most important thing is moment and technique of harvesting,” he told me. In a pinch, he used two black bamboo plants from his property to build Finca Exotica’s yoga platform. It has held up better than he expected, and he will use it again.
Because it doesn’t hold up well against sun and rain, Markus uses bamboo from knee level and above for Rancho Exotica’s buildings. Bamboo poles provide structure for the thatched walls and thatched roofs of the cabanas and tiki tents and soars in an elegant timberframe-like structure that makes up the rancho, where the restaurant, lounge and library are located. Copious use of bamboo is one Markus’s four self-determined principles of sustainable building, which also include using as little concrete and hardwoods as he can and keeping the footprint as small as possible. “On the Osa, the culture encourages the smallest footprint,” he says. Pointing out a tiki tent that was built using only 12 babmboo poles, he says, “We’re trying to see how little we can use. That’s kind of a fun culture, to see how close you can get to just enough.”
Bamboo is not a good material for foundations and foundation posts, so Markus cajoled a local sawmill into saving him the scraps and cutoffs from hardwood boards, which were being thrown over a fence and gathered for firewood. “They had fields full of this stuff, some of it hardwood that can last hundreds of years,” he told me, adding that he’s also using the scraps to build terraces for “edible hill,” a vast garden that’s in the works. For a cabina he just completed, he let the size of the boards and beams determine height and width—so he wouldn’t create scrap wood of his own.
Many of the cabinas and tents are roofed with swita, a native grass that must be harvested within three or four days after the full moon—or it will rot in three years. Once abundant on the Osa Peninsula, swita has become popular and scarce. “It used to be poor man’s thatch, used on little cabins,” Markus says. “But the monster houses started using it, and now we have no swita left.” For more recent buildings, Markus is using tin—very typical in the vernacular construction here—although he admits that he’s still trying to find a way to “make it sexy.”
Just this year, Markus and Gabriela completed a large covered banana-shaped rancho that is the hub of Finca Exotica’s activities—where guests feast, socialize, relax on hammocks and take in the view. Inspired by Christopher Alexander’s Pattern Language, Markus says that the most important pattern in this—and all of his buildings—is positive outdoor space. A concrete core houses the pantry and storage area for the rancho’s open-air kitchen, where Gabriela can be found making magic of her farm’s bounty. Choosing between the lesser of two evils, Markus used a minimal amount of hardwood rather than concrete for the foundation, Markus, Gabriela and their staff spent four years hauling up stones from the beach for the foundation walls. A tin roof is lined underneath with reed for heat and sound insulation. (It gets pretty loud during the worst of the rains.) Then they transplanted six palm trees in strategic spots around the rancho for shade.
Once a disciple of rectilinear Bauhaus architecture, Markus had an epiphany during a train ride through Germany 10 years ago, when he realized that every building had become the same—square, spare and modern. “My beloved right angle has been betrayed,” he says. “So, no more strict rectangular modernism.”
With their curves and conical roofs, Finca Exotica’s buildings tuck into the lush hillside as if they’ve always been there. They are perfect for this place—but not what Markus thought he’d build when he landed here. “When I got here, I wanted to make something impressive,” he says. “It took a little longer for the permits, and I learned to keep it small. The designs were shrinking every year we had to wait for permits.”
Markus has come to love the way his buildings have organically unfolded—wild and unstructured, like this peninsula itself. “If you had showed me this 10 years ago and said I would build this, I would have said, no,” he says with a grin. “But if we don’t do something wild, who will?”
Photo above: An elegant weaving of bamboo poles makes up the roof of Finca Exotica's rancho, shot while it was under construction. Photo by Barbara Bourne