There’s a way of building we call the “Timber Tent” that we hope might change construction in tropical and sub-tropical climates. While the term is new, some of the techniques are quite old, dating back past the beginning of the Thermostat Age… they’ve just been forgotten in the rush to build drywall-slathered boxes everywhere around the world, irrespective of regional conditions, climate, or culture. We’ve just returned from Mahogany Bay Village, just a stone’s throw from the shores of Ambergris Caye in Belize with lots of great images of the SmartDwellings now being completed there. But before getting into all the details, let’s have a look at the Timber Tent principles behind it all.
Tropical design is hard to understand for most American architects who have been trained to think of the exterior wall as a barrier between exterior and interior conditions, and where most systems are designed to slow the flow of outside conditions to the inside so the equipment can keep us comfortable indoors. Northern buildings might be surrounded by air that is seventy degrees colder (or more) than indoor air, which gets very dry in winter. Tropical air is hardly ever more than twenty degrees warmer than our comfort range, but it’s usually loaded with humidity.
Buildings in or near the tropics therefore need to open up and breathe. The prime function of the tropical building envelope isn’t to isolate conditions inside from conditions outside, but rather to channel conditions in order to make it most comfortable inside. In short, it’s a completely different way of thinking about the building envelope, and designing this way creates buildings built more like a durable tent than a multi-layered box.
Tents are pitched with thin panels stretched across a rigid frame. Tents can open up in several ways. Their sidewalls can be rolled up to let the breeze blow through, or dropped to conserve heat on a cool evening. Tent flaps can open in isolated places to catch breezes or views. We do similar things with the Timber Tent. We first build a post-and-beam structure for much of the building, then we fill in between the posts, largely with louvers, doors, windows, and shutters that allow us to either steer or exclude the flow of breezes to create the greatest comfort. Louvers can be operable or fixed as needed. Doors can be swinging or rolling. Windows that aren’t louvered can be swinging or double-hung, and shutters can be side-hinged, top-hinged, or rolling. In short, there are lots of options.
I spent three nights last week in the “Dream Suite” at Mahogany Bay Village. I call it this because the design of the suite came to me in a dream one night several years ago… the only time that has ever happened to me in my career. But regardless of its origins, it was my chance to see firsthand whether our ideas actually work at Mahogany Bay.
The short answer is a resounding “yes”. I slept with all the louvers open, and drifted off to sleep with the soft windsong moaning through the louvers. Between photo shoots, I worked furiously in the Dream Suite to get as many photos processed as I possibly could. The first day featured a blazing sun in a glorious clear blue sky, but the sea breeze kept me deliciously cool all day, sheltered under the reflective metal roof that bounced most of the sun’s heat back up into the sky without ever getting inside the cottage. And the heat that did get in was free to rise into the rafters, several feet above my head.
The breeze died down on the last day, and the heat rose into the upper nineties by noontime. While I spend a lot of time outdoors when I’m home and am therefore comfortable in the shade on many subtropical days, the upper nineties are simply too hot for me. But no problem… when I felt the warmth rising beyond my comfort range, I merely closed the louvered windows and cut on the ceiling fan. And because a ceiling fan’s breeze lets you feel comfortable ten degrees warmer than in still air, I felt great all through that sweltering afternoon. And while every unit in Mahogany Bay Village has a small air conditioner, I never needed to cut it on during my entire time in the Dream Suite.
Lots more to come over the next several weeks… what would you like to talk about next?
Snippets to Share
Ceiling fans keep you comfortable ten degrees warmer than still air and are 1/40 the cost of running central air.
Few things are as pleasant as falling asleep to wind song, which only happens if your house can breathe.
Drywall is just wrong in the tropics, where air is moisture-laden. With drywall, not dry = no wall.