How Buildings Learn: What Happens After They're Built

by Stewart Brand

The lesson for the ages from three-aisled structures is that columns articulate space in a way that makes people feel comfortable making and remaking walls and rooms anchored to the columns. You can always visualize what you might do next to improve the space plan. The recent engineering triumph of huge free-span interior spaces is actually a loss for intuitive adaptivity. The effect of wide-open space is oppressive rather than freeing.

The space plans of vernacular buildings are typically generic and general-purpose. The identical bays of three-aisled structures and the additive identical rooms of courtyard houses had been found to be the most inexpensively adaptable over time. Vernacular design is always prudent about materials and time, seeking the most pragmatic building for the least effort and cost. It provides an economical grammar of construction. Let there be a central passageway and stair hall, say, with roughly identical pairs of rooms on each side upstairs and down. (That was the “double pile” house that the fathers of George Washington and James Madison built and that pervaded eastern America.) The specifics of material, style, and finish were left to the builder and dweller.

Folk architecture that appears unified, homogeneous, even identical becomes, on closer inspection, rich, diversified, and individualistic.

patriarch J. B. Jackson has remarked, “The older I get, the more interested I get in the future that’s waiting for us. I don’t think it will have much dignity, but it will have vitality.”8

“While the popularity of classicism has certainly waxed and waned, there hasn’t been a period in over two millennia when someone in some part of the world hasn’t been fitting architraves across column tops.”9 Modernism swore it would get rid of these pagan temple ornaments forever, and the first thing Post-Modernism did was put them back.

Something evidently drives continuity between buildings at a mythic level. Masonry fireplaces and chimneys have been utterly obsolete since the popularization of the Franklin stove by the 1830s, yet 160 years later every house that can afford it still has at least a facsimile of a masonry fireplace and chimney. Some deep lullaby croons, “Hearth and home.”

How did running water, bathrooms, central heating, and air conditioning originally get into houses? Not via architects.

In the older world [of Europe], the public facilities tended to copy the private. Inns were shaped like large private residences, town halls were fashioned after the palatial dwellings of rich citizens. But the urban communities which sprang up in the United States in the nineteenth century were bristling with newcomers, while there were still few rich men and, of course, no ancient palaces. Here public buildings and public facilities made their own style, which gradually influenced the way everyone lived.10 It was raffish commercial buildings rather than the stately institutional ones that led the way. Grand hotels, which historians consider to be an American invention, introduced gas light, spring mattresses, running water and central heating by mid-19th century. Guests soon took insistence on such luxuries home with them. Once people had experienced air conditioning in movie theaters in the 1930s, they could not bear to live without it at home. Maybe home adoption is the final test of the success of a new building element. That the sealed windows and services-hiding dropped ceilings of offices have not migrated to the home may signify that they are ultimately failures.

Sometimes a building form takes off and becomes so widely popular that its design is assumed to be anonymous—“folk”—when in fact it was some individual’s bright idea. America’s roadside service stations were largely created and continuously updated, right up to the time of interstate truck stops, by one man.

It may be that one of the reasons architects are so driven toward surface originality is that their industry compels them to uniformity throughout the rest of a building. Caught between the rigid requirements of building codes, the standard solutions of professional books such as Architectural Graphic Standards, and the standard products of Sweets Catalog, there is not much room for creativity, so architects grab what they can.

This is a gain and a loss for quality in buildings. The worst are less bad because of having to meet fairly intelligent standards. But the best are less innovative as a whole, and they are less likely to be finely adapted, or adaptable, to their unique circumstances. Instead of learning from each other, such “catalog architecture” buildings are guided by a standard homogenized pool of building lore which is no longer regional and often not even national, but world-encompassing, inescapable and unchallengeable. How else can we explain the survival from decade to decade of the aluminum-frame sliding glass door? It seems to serve simultaneously as door, window, and wall, but it’s terrible at all three. As a door it’s fiddly and awkward to open, and dangerous, since it has the vicious property of looking the same when open or closed, and people walk smack into the glass. As a window it reveals too much in both directions and makes any view quickly boring. And it’s worthless as wall, being nonstructural and noninsulated, bleeding heat in whatever is the wrong direction. The sliding glass door is a measure of how remote the builders’ decisions have become from the users’ experience and of how powerless users are in the face of standardized building doctrine.

When the ladders were drawn up, the complex of several hundred rooms became a fortress against raids by Navajos and Apaches. New rooms were added casually to the top of the structure, turning former roofs into floors and terraces. The terraces were public walkways and the site of family activities such as food preparation.

What about the tourists? In a 1912 speech the archaeologist/booster Sylvanus Morley had proclaimed: None of us may live to see the day, but sometime in the future there will surely come a generation of Santa Feans who will not be eternally sleeping at the switch; but who will realize the possibilities of a Glorified Adobe City, and reap the golden harvest therefrom. Then, and not until then, will Santa Fe enter upon the epoch of increased and ever increasing prosperity, which is hers by right of every association, historic, geographic, and climatic.17 In 1992, newspapers reported, “Santa Fe, NM, bumped San Francisco from the top spot in Conde Nast Traveler’s annual Readers Choice poll as the best travel destination in the world.”18 A home-decor style book titled Santa Fe Style19 was a national bestseller. All through the 1980s, “Santa Fe” shops and restaurants permeated America’s malls and airports and even invaded Europe. The galleries of tiny Santa Fe became America’s third-largest market for art, following New York and Los Angeles. Commercializing vernacular had turned adobe into gold.

A mobile home is an instant house. You wheel it in one day, hook up to the local utilities, and you’re home. Everything works—plumbing, wiring, heating. It was all assembled in one smooth operation at a factory out of light wood frame on a steel chassis, clad with aluminum sheeting. The roof of white-enameled metal reflects the sun and sheds rain better than most site-built roofs. Half of all mobile homes are in specialized parks, among the last real communities in America, drawn together in part by physical closeness, in part by the need for political solidarity against enemies.

Mobile homes are always being attacked. By aesthetes for their appearance. By bigots for housing the “wrong” people. By the construction industry for “unfair” competition. By local government for paying insufficient taxes. (In fact, mobile-home park operators usually provide services such as sewage, water, garbage, and thoroughfares that government is spared paying for.) Many counties simply outlaw mobile homes. In 1970 the federal government recognized that most of the nation’s low-cost housing was in mobile homes, and it set out to help the industry, but it messed up. HUD (Housing and Urban Development) came up with such a burdensome set of regulations that small manufacturers were driven out of business. Allan Wallis points out that “the smaller manufacturers, who needed a distinctive product to compete, were often a source of design innovation.”29 A highly creative industry was made stodgy by the strictures of approval.

In no small part the success of the mobile home as a form of industrialized housing must be attributed to the fact that it readily permits user modification.”

Mobile homes are openly make-do, unfinished. They embody the vitality and unembarrassed lack of dignity that J. B. Jackson sees enlivening the American future. They demonstrate vividly that however much buildings may be sold as a product, they are lived as a process.

MOBILE OFFICES, just bare shells with a few windows and rudimentary services, are perhaps the most flexible and widely used of contemporary Low Road buildings. You see them used as film studios, classrooms, government offices, and on-site construction offices, as here on King Street in London. I confess that I looked at the highrise being built and wondered, “Why bother? Why not just keep stacking these things?”

So, what do the successes of Cape Cods, bungalows, and mobile homes tell about the vernacular process in industrial times? For one thing, vernacular is no longer regional, except in detail. (Mobile homes in really hot climates, for example, often grow an extra roof to ventilate away the radiant heat from the sun. In cold climates, pitched roofs are added to shed snow.) Successful building forms are broadcast nationally, driven by the national market economy. Builders and developers imitate the most successful of their competition. That is how buildings learn from each other in this century. Whatever buyers flock to will proliferate.

More than either Cape Cods or mobile homes, bungalows spread a pattern language—big homey living room with prominent fireplace, conveniences and furniture built in, connection to the outdoors, horizontality.

As for the elite: what might be accomplished with their abundant intelligence and creativity if architects really studied the process and history of vernacular designs and applied that lore in innovative work? We might get buildings that could be as original as needed, but still would feel profoundly familiar and right, and would invite change. It would be a relief after all those smugly decorous buildings that “refer to” stylistic details of one vernacular tradition or another and miss the integrated lore. Of all buildings they are the most maddeningly perverse. They look like they should work, and don’t.

Too eager to please the moment, over-specificity crippled all future moments. It was the image of organic, not the reality. The credo “form follows function” was a beautiful lie. Form froze function.

In architect Sim Van der Ryn’s modern translation, “Everyone who can afford it wants their home to be a nightclub big enough to entertain and impress everybody they know.” High-end houses are vastly oversized and overpriced as a result, and low-end and middle houses are always installing tokens of immensity such as jacuzzi baths, coach lamps, foundation planting, and swimming pools.4

Do-it-yourself home improvement is a huge, growth industry. Back in 1980 Americans spent $44 billion on home improvement materials, tools, books, etc. And that was a fraction of the real economic event; the value of the unpaid labor involved—and the final improvement value—has never been estimated. Nevertheless by 1990, ten non-inflationary years later, the annual amount spent had nearly tripled to $110 billion, and the collapse of real estate would send it higher still as people replaced trading up with fixing up.6 A book titled The Router Handbook (a router is a power tool for specialized shaping) sold 700,000 copies between 1983 and 1990—ten times greater than Witold Rybczynski’s bestseller, Home: A Short History of an Idea. Go ten times greater still to 8 million, and you have the worldwide sales since 1973 for the Reader’s Digest Complete Do-It-Yourself Manual.7 That’s the amateur work. In 1980 professional home remodeling came to $46 billion (this number includes labor). By 1990 it was $107 billion.8 There’s an interesting reversal in those numbers—in 1980 more was spent on professional remodeling than

We begin to understand why site-built, platform-frame houses have persisted so long in America. Site-built is site-rebuildable, much more than factory-made housing, even mobile homes. Platform frame—2-by-4 wood stud walls raised a floor at a time—is an amateur medium. You can build or rebuild an entire house with a power saw and a hammer (I did so once in Nova Scotia). For reasons unknown—perhaps our frontier history—Americans revel in doing major home projects themselves, and so we stick with forms that give us that freedom.

Most painful of all is when the expensive improvement turns out to be worse than what it replaced. In recent decades many older houses in the American south that used to be up on wood or masonry stilts were decreed by their owners to look “poor” that way, so the open sides were boarded in. This cut off ventilation—the original reason for the stilts, forgotten when the local vernacular pattern language died—and termites and rot quickly brought the buildings down. Another frequent error is installing built-in furniture. It works beautifully when the goal is to save space, as in bungalows, but it petrifies rooms around one ephemeral function. Soon enough you have to demolish the walls to move the furniture.

“Our most important responsibility to the future is not to coerce it but to attend to it,” observes city theorist Kevin Lynch. “Collectively, [such actions] might be called ‘future preservation,’ just as an analogous activity carried out in the present is called historical preservation.”7 “Future preservation” means that the building is not only built to last, but it remains always capable of offering new options for its use. Freedom to adjust and even to change direction entirely is preserved.

More specific to buildings: overbuild Structure so that heavier floor loads or extra stories can be handled later; provide excess Services capacity; go for oversize (“loose fit”) rather than undersize. Separate high- and low-volatility areas and design them differently. Work with shapes and materials that can grow easily, both interior and exterior. “Use materials from near at hand,” advises Massachusetts builder John Abrams. “They’ll be easier to match or replace.” A spatially diverse building is easier to make use adjustments in than a spatially monotonous one—people can just move around. Medium-small rooms accommodate the widest range of uses.10 When in doubt, add storage. Add nearby storage—closets, cabinets, shelving; and deep storage—attics, basements, unfinished rooms without windows. What begins as storage can always become something else, and if it doesn’t, there’s never enough storage anyway.

Shun designing tightly around anticipated technology. As energy analyst John Holdren says to all futurists, “We overestimate technology in the short run and underestimate it in the long run.” So design loose and generic around high tech. You will be wrong about what is coming, and whatever does come will soon change anyway. Playing out in imagination the potential consequences of even minor-seeming details is worth doing. (“We could put a tall window with a low sill here so it can be changed easily to a door later when we add the deck. But what if the deck turns out to be a porch and it winds up somewhere else because of a tree or something, and a drunk guest walks through the tall window one wintry night?”) Scenario-makers love imagining disasters. They are right to do so.

If you design a building that you think tourists would admire and envy in ten years, and that preservationists will fight to save in fifty years, you’ll probably get the proper mix of bemused conservatism and mythic depth. Freed of fashion, a building can become honestly interesting in its own terms.

As for shape: be square. The only configuration of space that grows well and subdivides well and is really efficient to use is the rectangle. Architects groan with boredom at the thought, but that’s tough. If you start boxy and simple, outside and in, then you can let complications develop with time, responsive to use. Prematurely convoluted surfaces are expensive to build, a nuisance to maintain, and hard to change.

The hall averages six feet in width for the entire depth of the box. Because its dimensions are generous, it can accommodate functions beyond circulation. Bathrooms can be squeezed in, leaving a three-foot passage, adequate for walking. Closets can be placed wherever leftover space occurs, easily leaving some three feet of hall space. The interior stairs are a standard item always inserted in the front of the house near the entrance, accentuating the grandeur of the hall. The rear of the hall, which can have prime access to light, can then form a single small room. Thus the hall, which diagramatically appears like mere circulation space, becomes the support core that relieves the rest of the box of clutter. The generous width of the hall is also the major reason for the inherent flexibility of the box.

If you want a lovable building, a strategic decision needs to be made right at the beginning. The design and construction can fruitfully take either the High Road or Low Road, toward beloved permanence or toward beloved disposability. The High Road requires Structure built to last and some areas of very high finish indeed, particularly with the Skin and at least some interiors, to set a high standard for future work. The major threat to an urban High Road building over time is shifting real-estate values, so either a financial endowment or great public esteem is needed to protect the property.

A Low Road building needs only to be roomy and cheap. Structurally it should be robust enough to take the major changes in use it will attract. Finish can be minimal and ornament modest or absent entirely. Initial Services can be rudimentary. Design it primarily for storage and it will soon attract creative human occupants.

Longevity has no chance without serious Structure. “A building’s foundation and frame should be capable of living 300 years,” says Chris Alexander. “That’s beyond the economic lifetime of any of the players. But construction for long life is what invites the long-term tampering it takes for a building to reach an adapted state.” The lack of economic incentive suggests a role for government, using building codes, tax credits, and even direct sponsorship to get buildings that will serve the community for generations. Some of the solidest buildings in America were constructed during the 1930s by the New Deal programs of the Public Works Administration and the Works Projects Agency—libraries, schools, park buildings, bridges, dams, viaducts. That investment by go...

Some industries, led by the German auto manufacturers, are adopting “design for reuse” (DFR) and “design for disassembly” (DFD) engineering. Design for disassembly in building construction is doubly appealing because it invites later reshaping of a building even at the Structural level.

Nailing light-construction buildings together, for example, is archaic. It’s as easy to power-drive (and undrive) self-tapping screws, and the cost of lumber keeps going up, making wood valuable enough to recycle.

Wood is already the most adaptive of all building materials because amateurs are comfortable messing with it. Easy disassembly would help even more. When stud walls were first invented in Chicago around 1833, the technique was call “balloon frame” derisively because it looked so weak and ephemeral. It wasn’t weak at all, but it was relatively ephemeral, certainly when compared to the old timber frame buildings with their massive posts, beams, and rafters fastened together with clever joints and wood pegs. Timber frame was the original design-for-disassembly building material—just knock out the pegs.

I see no reason for most American housing still being made of wood 2 × 4 studs. Nearly all new European houses, most Japanese houses, and nearly all American commercial and institutional interior walls are made with steel studs. Galvanized steel studs are cheaper, lighter (one-fourth the weight of wood), straighter (no warp), easier to cut (metal snips), and conveniently holed for stringing conduit and pipe. They don’t burn or rot. They stack compactly. They take less skill to work with than wood. The steel itself is over 60 percent recycled. And being quickly assembled with wallboard screws, steel stud walls can be as quickly taken apart and reused. I’ve seen interior sheetrock-and-steel-stud walls for an office installed over the wall-to-wall carpet that was laid down first for the whole floor. Now that’s casual.

It strikes me that external walls can take either a High Road or Low Road approach, encouraging either permanence or change. In some buildings you might want the front to be impressively High Road and the back adaptively Low Road. Low Road walls offer a further choice—they can be funky or high tech. One of the best of the funky is the highly forgiving board-and-batten. It doesn’t need precise fitting and can ignore wood expansion and contraction from moisture and temperature. Anybody with a hammer and saw can make or unmake a decent board-and-batten wall. For high-tech Low Road walls, the current acme is the variations on Dryvit known in the trade as “exterior insulation and finish systems” (EIFS). Light and cheap, they are factory-made panels of stucco and foam insulation bonded together, shortcutting weeks of work in wall construction. They can be molded to decorative shapes and look right nice in a movie-set sort of way, at least for a while. If they show dents after a few years, or the bonding compounds loosen, it is no great loss to replace them, maybe with something more lasting.

Anyone who buries services in the walls should adopt the practice of design/builder John Abrams in Martha’s Vineyard, Massachusetts (who will emerge as the hero of this chapter). In all his buildings he has a ritual just before the walls close, when the services are installed but the sheetrock hasn’t been put on yet. He walks methodically through the building photographing every open wall and ceiling and keying each photo to a set of plans. He discovered that the procedure gives him a chance for close overall supervision of the job at a critical moment, but the main purpose is to record precisely where all the services are before they get hidden—every duct, pipe joint, and outlet knockout. The color photos are then assembled with the keyed plans in a ring binder, which is known as “The Book” throughout the rest of the job. The electricians, finish carpenters, and other subcontractors consult The Book as often as they do the building plans. The electricians look to see if there’s enough slack in the wiring to move a light switch; the carpenters want to know where the blocking is for nailing the trim. At the end of the job, Abrams ceremoniously turns over The Book to the owners. With the passing years it becomes ever more precious for repair and remodeling, as original memories fade and construction practices change. Eventually it becomes a major item in the resale value of the building. It costs almost nothing to make.

Can a building learn while it is being built? Here we come into the realm of theorist/architect/contractor Chris Alexander. He insists that architects can’t really visualize how a building will look and feel, nor can anyone else—no matter how computer-enhanced they are—and so construction should be a prolonged process of cut-and-try. “Everybody wants to zoom,” he says, “and you mustn’t. You are constantly finding out about the building while constructing it, and what you will find out is inherently and necessarily unpredictable. You are watching a developing wholeness.”

Chris Alexander believes in making models. Not just one fancy presentation model but whole lineages of rough models, with everyone who will use the building getting a chance to study and critique the best of them as they evolve. Gradually the models grow in scale until they are life-size and at the site—chalk lines on the ground or the floors, tentative portions of the building jury-rigged of cardboard or cheap plywood. Opulent buildings like the Library of Congress or the Bundestag building need proportionally elaborate models to test for potential folly. Computer modeling and simulation can be helpful, but it can also misdirect designers toward illusory “optimal” solutions. These are inevitably brittle—they work only under one set of conditions. Computer-aided design (CAD) has led to weaker building that can’t handle unusual circumstances such as hurricanes. Before computers, engineers dealt with uncertainty by building in a large safety margin. They were right. Oversize your components.

The cut-and-try approach can lead to doing some parts of a building quick and dirty with the idea that they will be temporary tests. If they work well, one imagines, they will be improved later. If they don’t work, it’s no loss to replace them with something that works better. This can be a wholesomely Low Road invitation to later refinement, but beware: in the real world “temporary” is permanent most of the time. If the cheap trial worked, it will be left alone, no matter how funky it is. If it failed, it’s embarrassing to fix. Life rushes on to more pressing or interesting problems. Once “finishing” on a building begins, the guessing and trying multiplies. Contractors know that when a building is fully closed to the weather, the job is only half done. A maddening amount of debate and adjustment is coming. Even so simple a thing as paint color gets complicated. An anthropologist friend of mine studied paint-purchasing behavior for an advertising firm. It turns out that people can’t guess from the sample chips in stores how paint will actually appear on a wall. “They buy a quantity, go home and paint half a wall, groan at how it looks, and then they bring it back to change the shade, usually by lightening it.” Try modeling that on a computer; it’s worse than sample chips.

When it came time to figure the height of the tilt-up Corian cutting board, Patty stood with vegetable knife in hand and the contractor measured the distance from the blade to the floor. We did the same with the kitchen sink and the refrigerator, positioning both much higher than the norm, so we reach into the refrigerator without calisthenics and wash the dishes without backache. Our home fits us like tailored clothing.