Monday, October 22, 2018

PROPER SOLAR ORIENTATION: It's More Than Just Facing Mecca

Developers just want to cram the most houses possible
on their sites—they don't give a damn about solar orientation.
Years ago, when I used to design the occasional tract house, I was always at odds with developers over solar orientation. Those guys are used to plopping down houses any which way that they’ll fit on a site—the more the merrier—and they don’t give a hoot about where and when the sun comes in. I went round and round with one developer in particular, trying to make his houses more livable. Forever after, when I mentioned the term “orientation”, he would roll his eyes.

“Here we go again,” he would complain. “Arrol’s houses always have to face Mecca.”

 The ancient Persian city of Yazd reaches temperatures
well over 100 degrees in summer—yet the tall structures
known as "badgirs" (windcatchers) in the background
have helped keep people cool for one and a half millenia.
Well, the idea of facing Mecca isn’t really that far off. Islamic cultures have long had well-established guidelines about which way buildings should face, and not just for religious reasons. In a climate often far more severe than our own, they used well-placed openings for warmth and light and mass walls to store the sun’s energy. And because cooling was at least as big a problem as heating in Islam, builders used decorative window grilles for shading, wind scoops to provide natural ventilation, and the earth itself to help stabilize interior temperatures. Even today, most of these millenia-old features are still considered radical solar devices by some folks here in the States.

By contrast, the Engineering 1 Building at IIT,  built in 1968,
still shows the western architect's total indifference
to proper solar orientation. Note the ragtag collection of
window shades hastily installed behind its glass facade.
Architect: Myron Goldsmith
(Image courtesy of Joe Ravi, CC-BY-SA 3.0)
The Chinese developed an even more elaborate set of guidelines for good orientation known as the feng shui—literally, “wind and water”.  While its precepts have become shrouded in mysticism over the centuries, its basis lies in common sense. For one, the feng shui favors houses exposed to the south and sheltered from the north as being most auspicious—in other words, the most comfortable. Nothing could be more basic; yet western architects have managed to bungle these obvious principles for more than a century—in fact, ever since they’ve had access to artificial light and mechanical heat.

Only the gas crisis of the late 1970s
finally woke Americans up to
the need for resource conservation.
Ancient cultures didn’t have the options of turning a thermostat up or down or switching on a light, however.  They necessarily understood the principles of solar orientation far better than many modern architects:  If they hadn’t, they’d have all been either roasted or frozen to death. Our own so-called “energy-efficient homes”, while certainly more comfortable than ancient ones, are at base hardly more sophisticated.  We’re just recycling what ancient builders have known for thousands of years.

Good solar orientation doesn't just save money—
it makes a home worth living in.
Even at that, it was only the oil shortages of the late 1970s that finally roused Americans from utter indifference to orientation. In a sense, it was the best thing that could have happened: tremendous strides have been made in residential energy efficiency in the past forty years as a result. For the most part, these improvements have been in mechanical heating systems and the related area of insulation—probably a good thing, since under the current administration, it seems unlikely that we’ll wean ourselves from oil dependence anytime soon.

But while it’s commendable that newer furnaces and water heaters can squeeze more heat from your petrodollar, and that better insulation now helps conserve that heat, the real foundation of energy efficiency is still what it was 2000 years ago: solar orientation. A well-designed house with south-facing windows, proper shading, and good ventilation will require less energy and be more livable than one without—end of story. Of all the things you choose to fret over in your own designs, the very first should be sunlight, and how it's going to get in.

Take it from a tract-house veteran:  You don’t have to face Mecca.  Just plain south will do.

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