Monday, January 27, 2014


If you’ve ever seen a picture of Stonehenge, the prehistoric monument near Salisbury, England, you’ll recognize the structural system known as post and lintel. It consists of two upright blocks--the posts--with another block--the lintel--spanning the gap between them. This was the earliest type of structure used to span open space.

The trouble was, the widest distance you could span with a post and lintel was limited to the size of the biggest stone lintel you could get your hands on--not to mention lift into place. Hence, even the grandest ancient buildings under roof--Egypt’s vast temple at Karnak, for instance--were little more than forests of stone columns with narrow passages left over in between. 

The invention that finally overcame this problem was the arch. It had humble enough beginnings. It was already known to the Babylonians, Assyrians, Greeks, and others, often in the form of a roof over underground drains. Yet the Romans were the first to really exploit its unique structural properties. They recognized that, unlike a lintel, an arch could span distances much greater than any single block in the structure.
Here’s why: A stone lintel carries a load by bending infinitesimally, which compresses the upper half and stretches the bottom half. Now, stone is strong under compression but fairly weak under tension, so the lintel has to be really deep relative to its span or it may crack.

An arch works differently. Because the wedge-like stones are arranged in a circular shape, placing a load on top squeezes the blocks against each other, compressing them but not putting them under tension. This takes much better advantage of the strength of the stone, and hence requires a lot less of it to do the job. 
Of course, an arch can’t just stand up by itself--something has to brace it on either side to keep it from spreading apart under load. Usually, a bit of solid wall serves this purpose. But you can also put a series of arches side by side to form a continuous arcade, letting one arch brace the next, as in the elevated Roman aquaduct known as the Pont du Gard near Nimes, France. 

Arches form the basis of even more useful structural systems, though. By stretching an arch into a tunnel shape you get a vault, an early means of roofing over space without needing intervening supports. By intersecting two vaults at right angles you get a groin vault, which the Romans used to roof their monumental Baths of Caracalla, among other things. And if you rotate an arch about its centerline, you get a dome--the basis of some of man’s greatest architectural works, from Rome’s Pantheon to Istanbul’s Hagia Sophia.

Ironically, since modern structures are now seldom built of masonry blocks, true arches are rarely used anymore except for dramatic effect or, occasionally, to support bridges, trestles, and the like. What’s most commonly used instead? Why, it’s our prehistoric pal, the post and lintel--though nowadays it’s made of wood, steel, or concrete.

Monday, January 20, 2014


A contractor once told me an interesting story about a house he’d built for a man in Connecticut. Winter was already setting in when he’d gotten the place weather tight, so as soon as he finished the fireplace, he built a fire in it to keep the house warm. When the owner found out, he demanded that the contractor tear out the bricks inside the fireplace and replace them because they’d gotten sooty. He told the contractor that he was paying for a brand new fireplace, and he was damned well going to get one.

This brought me back to a paradox I’ve pondered from time to time. When some people build, they become obsessed with getting everything absolutely perfect. It’s not uncommon for owners to have brand new materials ripped out again because they’ve picked up a tiny scratch or a little ding somewhere along the line. This happens even with materials predestined to show age or wear from normal use--say, hardwood flooring, painted trim, or in the case of our unlucky contractor’s client, the inside of a fireplace. 

What’s odd about this obsession with newness and perfection is that the sort of buildings we seem to admire most--Europe’s storied old cottages, let’s say, or perhaps China’s ancient courtyard houses--are precisely the ones that are old and thoroughly beaten up, with a patina that bespeaks their many years of history. And “patina”, after all, is really just a nice word for the flaws that arise from age and use--if anything, it’s a sort of anti-perfection. And given that we covet the patina of age in old buildings, why do we place so much value on flawlessness in new ones?  

In architecture and construction, quality--soundness, durability, and fitness of purpose--is never negotiable. On the other hand, we’d lose very little in easing our compulsion for flawless surfaces. For one thing, time and Mother Nature never allow us the pretense of perfection for any length of time--something modernist architects have usually learned the hard way. Better to start with the assumption that our work will get a good thrashing over time, and design accordingly. 

One way to do this is to use materials that don’t demand a high degree of finish: Oiled wood, rough plaster, wrought iron, to name a few. Better yet are materials requiring no additional finish at all: Natural wood, stone, brick, textured concrete, clay tile, weathering steel, and tinted stucco, among others. Beside requiring negligible maintenance, all of these materials can absorb years of abuse, and in return just keep looking better and better. 

Take a look at much of today’s architecture, though, and instead of materials that improve with age, you’ll find mirror-polished surfaces, razor-sharp corners, and demanding and intricate finishes. Seeing these flawless designs in photographs, forever protected from the indignities of daily use, it’s no wonder so many of us have come to expect flawless results in our own projects. To this rarefied school of design, I suppose, a soot-blackened fireplace would indeed be seen as a thing that’s ruined and imperfect, instead of being testament to a human tale unfolding. 

Monday, January 13, 2014


Here's a textbook example of how NOT to reach your home’s front entrance. A while back, I came across this otherwise rather charming house that was set back quite a distance uphill from the street. 

Alas, this is how you got to the front door: Assuming you even noticed the narrow flight of concrete steps hidden among the shrubs and didn’t clamber up the driveway instead--as most baffled visitors did--you were rewarded with an additional hike over uneven and badly-spaced stepping stones that drifted aimlessly up the hill. At the last minute, the route swerved to avoid a huge tree and then just barely squeezed you in at the foot of another narrow, L-shaped stair.leading up to the front porch. 

Climbing up to the first landing got you an excellent closeup view of the electric meter, the gas meter, and a tangle of assorted power and telephone lines, along with the corresponding paraphenalia belonging to the neighbor’s house. A final flight of steps to the left aimed you straight into a spiky, towering juniper bush, enroute to which you might just happen to notice the actual front door in a recess to your right.

So let’s look at each of these problems in turn:

• The beginning of your entrance approach should always be clearly discernible from the sidewalk. If it isn’t, call attention to it with a lamppost, a mailbox pylon, a gate or some other distinguishing feature. The approach should also be entirely separate from the driveway, so that people don’t have to pick their way around parked cars and oil stains to get to your front door.

• Outdoor stairs and steps need to be both broader and shallower than the ones used inside a house. Make them at least six feet wide, and even wider if appropriate. Stair risers should be no more than six inches high, and treads no less than eleven inches deep. Traditional porch steps can be a bit steeper, but in general, the easier the climb, the better.

• Your entrance path should follow a clear, rational course. If you’re after a formal approach, derive your layout from just a few basic geometric shapes. For a more naturalistic result, combine no more than one or two strong curves, and avoid feeble, tentative changes of direction--you cannot get a picturesque effect just by making your approach meander aimlessly. Avoid a layout that points people toward immovable objects like trees, bushes or blank walls--a path in nature invariably winds between obstacles, not directly toward them.  Above all, whether your approach is formal or informal, don’t make the layout too complicated, or it’ll lose its visual power. 

• Lead people past the best features of your front yard, not its worst ones. Consider potential vistas from various angles, ways to showcase favorite plants, opportunities for benches or other stopping points, and the possibility of water or arroyo features, however modest. Conversely, avoid routes that look onto gas and electric meters, garbage cans, garage doors, heat pumps, and other utilitarian features.

• Lastly, make sure the final leg of your entrance approach points people clearly toward the front door, and nowhere else. This is especially important if there are patio doors or other exterior doors nearby. There should never be any doubt about which door is the entrance.

Wednesday, January 8, 2014


In the days of laborious hand crafting, before the coming of the Industrial Revolution, ornament such as carving or engraving was a hallmark of extraordinary quality. Yet after the advent of mass production in the mid nineteenth century, automated machinery was able to replicate the most elaborate decoration at nominal cost, whether for a piece of furniture or a whole house. 

This literal cheapening of ornament set off a popular craze for mass produced items encrusted with decoration--not necessarily of high quality--and also began a trend of treating an object’s decoration as separate from its functional aspects. Hence, many late Victorian items, whether clocks, couches, or cast iron stoves, are positively wriggling with superfluous ornament, blithely gleaned from a jumble of periods and slathered on like so much wedding cake frosting. 

Likewise in architecture, the mania for mass-produced ornament yielded a series of increasingly ornate home styles, culminating in the frenetically decorated Queen Anne houses of the 1880s. Eventually, these bombastic designs overhwhelmed even the general public’s vast appetite for gewgaws, fomenting the backlash known as the Arts and Crafts Movement.

The instance of technology changing aesthetics isn’t confined to the Industrial Revolution, however. In fact, we’re in the midst of another such period today, and for many of the same reasons. Until a generation ago, objects with complex shapes--say, lots of intersecting compound curves--were relatively difficult and expensive to design, tool, and manufacture. 

Automobile bodies, to cite an extreme example, had to be hand modeled in clay at full scale and their measurements painstakingly transferred to permanent dies for mass production--one reason it used to take three years to bring a restyled car onto the market. Today practically all of this work is done on a computer; and the full-sized clay model, if it’s used at all, is more often created by a digitally-controlled milling machine than by human hands. 

The same digital methods used to design cars are used in practically all manufacturing industries today. And inevitably, the comparative ease of creating complex forms by computer affects the design of these products--just as the ease of churning out ornament during the Industrial Revolution encouraged its rampant use and eventual overuse. 

Alas, among today’s product designers, the unfettered power to create complexity seems to have brought on a corresponding fear of simple lines and clear-cut themes. Instead, objects ranging from copiers to computers to coffeemakers are loaded with gratuitous curves, bulges and distortions that contribute nothing but baffling visual chaos. On the other hand, ergonomics--design for ease of use--seems to be more neglected than ever, despite the vast computing power that could be brought to bear in its service. 

For these two reasons alone, the tortured Baroque shapes of today’s digitally-designed objects will probably mark another historic low point in aesthetics, just as the Victorian era’s overuse of its own technology eventually brought its products to the very pinnacle of aesthetic absurdity. Whether today’s supremely busy yet ergonomically bumbling designs will eventually rank with those of Victorian times, we’ll find out soon enough.