Our buildings, ourselves.

SINCE THE END OF WORLD WAR II, MOST MODERN BUILDINGS HAVE BEEN ECOLOGICALLY ABUSIVE BOTH TO THEIR INHABITANTS AND TO THEIR ENVIRONMENT. BUT THAT'S BEGINNING TO CHANGE.

Compared to most species, homo sapiens inhabits an extraordinarily large portion of the earth. From the Inuit who circle the Arctic to the Bedouin who range across the desert of the Arabian Peninsula, people have found ingenious ways to live in climates for which our biology does not predispose us. Today, almost all of us live in places where we would die without shelter. Our buildings function as second skins--huge extensions of our bodies--protecting us from the elements, storing food, and regulating internal temperature. Through our buildings, we have become superorganisms, capable of evolving rapidly to adapt to life anywhere on the planet.

But profound problems have arisen with buildings since the advent of the industrial revolution. While mechanization has enabled modern structures to provide services once undreamed of--hot water on demand, precise climate control, lighting at the flip of a switch, remote communication, and even entertainment--it has also had more insidious effects. By magnifying human capabilities, buildings have also magnified some of our weaknesses; by insulating us so easily from the cold, for example, they have allowed us to forget what it costs to generate heat. In a thousand ways, the cheap conveniences of modern buildings have driven from our memories a kind of knowledge--painstakingly gathered by previous civilizations--that was once, and may still be, essential to longterm survival.

Today, as much as a tenth of the global economy is dedicated to buildings: to constructing, operating, and equipping homes and offices. In terms of materials, this economic activity uses even larger shares--one-sixth to one-half--of the world's wood, minerals, water, and energy. Blame for much of the environmental damage occurring today, from destruction of forests and rivers to air and water pollution and climate destabilization, must be placed squarely at the doorsteps of modern buildings. And many buildings do harm on the inside as well: they subject us to unhealthy air or alienating physical environments, making us both less healthy and less productive than we are capable of being.

The root cause of this architectural sickness lies within the tremendous complexity of our own society. The motive forces of industrialization--mechanization and specialization--have created an economy that straddles the globe and produces a vast array of goods and services. But paradoxically, this is also an economy in which individual people fill ever narrower roles, giving us little appreciation of our relationship to the larger world. These changes in our roles are directly reflected in the buildings we inhabit; as we become less responsive to our ecological connections, so do our buildings.

To begin with, mechanization has enabled miners and loggers to extract raw materials on an unprecedented scale. Yet, the remote locations of these activities tend to insulate consumers from such environmental consequences as massive deforestation or toxic runoff. The appetite for ever-larger homes continues to grow, untroubled by thoughts of their real cost. New U.S. homes--90 percent of which are framed in wood--have grown from an average 102 square meters in 1949 to 187 today, and floor space per person in new homes has more than doubled. Gopal Ahluwalia, of the U.S. National Association of Homebuilders, describes the phenomenon: "Everybody wants a media room, a home office, an exercise room, three bathrooms, a family room, a living room, and a huge, beautiful, eat-in kitchen that nobody cooks in."

Today's buildings are wasteful in other ways. From refrigerators to shower heads, the appliances typically found in them draw two to four times as much energy and water as the most efficient models available, making them cost more to use in the long run. The complex, hidden mechanical systems in buildings can also lead to extraordinary waste when they silently malfunction. In U.S. homes with forced air climate control, up to 30 percent of heating and cooling energy escapes unnoticed from leaky or uninsulated duct work.

And industrialization has split the building business into a maze of specialized roles--architect, engineer, financier, supplier, builder, inspector, broker, buyer, insurer, and sometimes, tenant. As a result, the parties who have the most influence over a building's ultimate form have become increasingly removed from what they make, and from the experience of inhabiting it. Instead, each participant behaves according to the imperative he or she faces, whether that be minimizing up-front costs, maxi-mizing a commission, or meeting a deadline. Meanwhile occupants often lack the knowledge and the tools to gauge today's complex buildings for some important characteristics: healthy interiors and low utility bills. And since consumers do not know what to ask for, they do not get it. The industry instead produces what is most expedient for it: generic, quick-to-build structures that tend to neglect long-term costs and health concerns.

Such buildings have come to dominate the landscape wherever modern commercial or residential "development" is at full throttle. Their conquest has been so sweeping, and their size and technical virtuosity so dazzling, that we tend to forget--if, indeed, we ever knew--that over the broad span of history, destructive buildings have been the exception rather than the rule. Impressed by the fashionable, high-tech look of most new houses or offices, we would never dream that these spaces could be more dangerous to health--directly and indirectly--than the more "primitive" structures of earlier times.

But for thousands of years, indigenous cultures have crafted homes that have sustainably exploited local resources--an elegant mediation between the vagaries of the weather and people's need for shelter and comfort. Since they couldn't expend huge quantities of oil, coal, or fir to stay comfortable, most people found that survival demands careful adaptation to local climatic and geologic conditions, and to the limits of local materials--whether wood, earth, straw or even snow. And since the people who lived in these buildings were the architects and construction crews, they rarely ended up in something they did not like.

Modern architects could gain much from emulating techniques traditional builders discovered long ago--for example, how to make walls from earth and how to make the most of the sun's rays in winter--yet they need not simply turn back the clock. Designers can now improve on ancient techniques without rejecting them, by integrating them into efficient new technologies such as insulating windows and low-energy lights.

The most important lesson that traditional architecture teaches is that making good buildings means making connections: understanding how the processes of designing, building, and operating affect each other, the occupants, and the environment. That will require architects, engineers, and developers to work together as a team. Each specialty will need to overcome its accustomed narrow-mindedness, in much the way that many technology companies outside the building industry have already done. Such an approach will continue to provide shelter for people without jeopardizing the health and livability of their greater home--the planet.

PROBLEMS ON THE OUTSIDE

Today, much of a building's environmental impact occurs before people ever set foot in it. The environmental consequences of a few months of building construction, mostly from producing and transporting the materials that go into it, are comparable to at least a decade of building operation.

Buildings account for roughly 40 percent of the materials entering the global economy each year: some 3 billion tons of raw materials are turned into foundations and walls, pipes and panels. (Much of the rest of the materials flow becomes roads, bridges, and vehicles to connect the buildings.) The lion's share of this tonnage comes from quarrying earth and rock (clay for bricks, gravel and sand for concrete, and stone for blocks), which leaves large wounds in the landscape.

But some of the less bulky construction materials, such as copper, steel, and plastics, entail far more environmental impact than quarry products because they require much heavier processing. For example, nearly half of U.S. copper demand--some 530,000 tons a year--ends up in buildings, primarily for pipes and electrical wires. Four-fifths of this is extracted from low-grade virgin ores, using a purification and smelting process that produces huge tailing piles: 99 percent of the ore is left behind. The process also generates one of the country's largest flows of poisonous chemicals, acid rain precursors, and heavy metals.

Modern buildings also pose threats to forests, accounting for more than three-fourths of the world's voracious appetite for wood. Two-thirds of the wood that goes into buildings is used for cooking and heating, primarily in developing countries. (These uses consumed 1.9 billion cubic meters in 1992.) The remaining third consists of lumber, plywood, particle board, and other structural materials.

And of course, buildings are major consumers of energy. One-third of global primary energy use is devoted just to keeping existing structures up and running. Manufacturing and transporting construction materials devours additional energy. Brick, steel, and cement, for instance, all require energy-intensive high-temperature manufacturing processes. In the United

States, according to one estimate, the total of all this "embodied energy" pushes the building sector's share of energy consumption to roughly 45 percent--more than all other uses combined. Systematic study would probably reveal a similar global figure as well. In terms of atmospheric emissions, buildings probably account for nearly half the global output of the greenhouse gas carbon dioxide, as well as half the output of sulphur dioxide and nitrogen oxides, the agents of acid rain. And buildings would have to take the blame for a corresponding share of the other environmental liabilities of energy production--oil spills, nuclear waste, the destruction of rivers by hydroelectric dams, run-off from mining coal, and mercury emissions from burning it.

A survey of water use in buildings tells a similar story. Domestic water use accounts for 8 percent of the world's fresh water consumption, and the strain on water resources is growing. From Beijing to Los Angeles, rapid growth in urban water consumption is depleting groundwater or encouraging far-flung projects that siphon water away from agriculture. Nuclear and fossil fuel power plants use another 20 percent of the world's water supply: half of the electricity generated is for buildings, bringing their share of global water consumption to about one-sixth. Almost all of the water used at power plants drains into rivers, pouring thermal and chemical pollution into downstream ecosystems.

Buildings produce waste on the same scale they consume: construction generates mountains of waste; demolition even more. In the United States, erecting the average home sends some seven tons of debris to the dump. And for every six houses or apartment buildings constructed, one falls to the wrecking crew--about 150,000 each year. Altogether, construction and demolition activity feeds 90 million tons of rubble into U.S. landfills each year. That amounts to half the tonnage that municipal governments annually collect from homes and businesses, but it garners far less attention from policymakers. In western Germany, construction and demolition waste actually matched municipal waste in 1990, at 24.4 million tons--enough to bury Bonn two feet deep.

PROBLEMS ON THE INSIDE

Inside their walls, the troubles with modern buildings have become a familiar phenomenon: "sick building syndrome." In 1984, an expert committee of the World Health Organization estimated that up to 30 percent of new or renovated buildings may experience such problems.

Often ventilation systems subject occupants to stale air for hours on end, or harbor and spread unhealthy molds. Sealed, climate-controlled buildings also trap volatile organic compounds (VOCs), particularly formaldehyde, that can seep out from adhesives and drying agents in furniture, paint, and carpets, often resulting in concentrations hundreds of times higher than those measured just outside. According to the U.S. Environmental Protection Agency, the medical and lost-productivity costs of workers breathing poor air amounts to tens of billions of dollars each year in the United States alone.

TABULAR DATA OMITTED

The rise of modern buildings has also resulted in a less quantifiable but perhaps more insidious problem. Traditionally, local materials and the demands of local climate tended to give each vernacular architecture its distinctive character. Today, what shapes buildings in industrial countries are the abstract theories of academic architects, the careful calculations of corporations and developers, and the short-run economics of the highly competitive development and construction industries.

From Japan to Canada to Italy, the result has been a proliferation of monotonous business and commercial neighborhoods mixed with garish commercial strips. The buildings in these settings rarely offer their visitors the psychological sustenance that comes with a sense of connection to the place where the structure was erected, or by extension, to a community.

MATERIAL CHOICES

One reason that construction today consumes so many more natural resources than it used to is that what people want from buildings and what they put into them have changed dramatically. Our demands on buildings, in terms of floor space and features, are rising rapidly. But as people move more frequently, as industries rise and fall, and as cities undergo convulsive development, people become less interested in investing in these massive capital assets for the long term.

As a result, buildings often wear out in a matter of decades, or are torn down to make way for new ones even sooner. To make the process of turning trees and rocks into modern homes and offices less destructive, builders will have to put up structures that are durable and flexible, make them out of carefully chosen materials, use these efficiently, and reuse and recycle them as much as possible.

According to writer Stewart Brand, there are several ways to make buildings more adaptable, so that they can endure in today's rapidly changing world. They should be built solidly, yet in a way that makes them easy to add on to later. Rather than being specialized for today's narrow uses, they should be general-purpose, to adapt to the unforeseeable needs of future occupants. Piping and wiring should not be embedded in a building's structural components, but left accessible so that upgrading for future needs can be done more easily.

One recent project demonstrates the environmental and economic advantages of rehabilitation over new construction. KBI, a large nonprofit housing association in Denmark, has begun upgrading old three-story apartment buildings by adding another floor at the top. This yields a 33-percent gain in floor space but consumes much less material than new construction would, and at two-thirds the cost. Along the way, energy- and water-saving features are added so that total resource use in the buildings stays the same.

Just as designers think about how to make buildings go farther, they should think about how to make the materials in them go farther too. Of the materials involved, wood is the one people have learned to use most efficiently, perhaps because forests are already disappearing in many places. In Montana, for example, the Center for Resourceful Building Technology recently built a house to demonstrate various wood-saving techniques. Instead of heavy timber framing, which requires long beams from mature trees, the walls are built of insulation sandwiched between panels made from glued-together wood scraps. The floor incorporates wooden I-beams, that, much like their steel counterparts, cut the amount of material needed by 75-percent without sacrificing strength.

Brick, concrete, and steel, too, can be used much more efficiently. Since the 1960s, the amount of steel used in new office buildings in the United States has fallen by two-thirds, as it has been replaced by less energy-intensive steel-reinforced concrete. In 1993, a new type of concrete, containing thousands of hair-sized steel wires instead of standard reinforcing bars, was developed in France. The new concrete need be only one-third to one-quarter as thick as conventional concrete, which increases the likelihood that both concrete and steel in commercial buildings will continue to decline.

Builders can make the materials they do use go even further by reusing and recycling them. In this respect, inorganic materials tend to work better than wood. Bricks, stone, and concrete blocks are easy to rescue intact from a building in demolition, and can last for millennia. St. Alban's cathedral, still standing in southern England, was built 900 years ago partly out of bricks from nearby Roman ruins now twice as old.

Even old concrete can be crushed and mixed with additional cement to make new concrete, a practice becoming increasingly common as landfilling grows more costly. In Sydney, Australia, a demolition crew recently knocked down a 41-story office building, sorted the rubble, and sent it off to the recyclers.

Structural wood, when pulped and formed into new beams, studs, or panels, can be recycled only a few times because the organic fibers are chopped shorter each time they are reprocessed. And where the building stock is growing rapidly, the demand for materials far outstrips the recyclable waste supply, so that even doubling wood efficiency may not suffice to rein in consumption to sustainable levels. Consequently, some parts of the world may have to move away from building with wood altogether, just as most Europeans did centuries ago after razing their own forests.

People in climates where organic materials are scarce have long made their dwellings out of the earth itself, a material with many environmental advantages. Ancient Chinese builders once rammed mud into rigid molds to make the Great Wall. Archaeologists have found millennia-old adobes (sun-dried mud bricks) in the Indus Valley and the Middle East. Much of Europe, from the British Isles to the Balkans, turned to adobe and rammed earth in the late Middle Ages as wood ran in short supply. To this day, an estimated 40 percent of the world's people inhabit earthen dwellings.

Unlike concrete and brick, rammed earth or adobe bricks do not require energy-intensive high-temperature firing. And earth suitable for construction lies close at hand in many parts of the world, which keeps transportation impacts low. Builders in Niger and Mali, for example, have worked with a French nongovernmental organization called Development Workshop to develop a technique for capping their buildings with domed earthen roofs that contain no wood yet remain strong, safe, and water resistant.

In industrial countries, where labor is much more expensive, some companies have mechanized earth building in order to compete with standard materials. Small diesel- or electricity-powered machines that can make up to 900 compressed earth blocks per hour have been put to work in Australia, Germany, Switzerland, and the United States. The ecological price of using these machines--in terms of energy use and pollution--is a fiftieth of that for concrete.

DESIGNING FOR CLIMATE

The use of distant fossil fuel and water supplies has replaced an essential part of traditional building: the application of craft to design and construction, to make the most of local resources. Architects used to site their buildings carefully, with an eye to water supply, prevailing breezes, or the winter sun. Today, they shape, size, and position their structures according to other expedients, confident that hidden, energy-guzzling mechanical systems will compensate for what would once have been ludicrous design.

Le Corbusier, the leading light of modern architecture and the creator of the residential high-rise, once proclaimed prophetically, "I propose one single building for all nations and climates." His gray concrete monoliths are now visible in cities everywhere, from Boston to Moscow to Tehran, their toilets, air conditioners, elevators, and heaters drawing on massive energy and water flows.

In contrast, the most resource-efficient approach to architecture is to eschew the use of machinery in favor of careful manipulation of basic design elements, often employing techniques that evolved over thousands of years. The result is a structure that alternately harnesses and buffers the sun, wind, and other natural forces in order to create comfortable indoor climates through all seasons at a minimal environmental cost. Since geography and climate vary from region to region, adaptive, passive architecture will do so as well. Thus, resource-efficient buildings will tend to exhibit more variety than resource-wasting ones.

Like warm-blooded animals, buildings need effective skins to maintain constant internal temperatures. The oil shocks of the seventies catapulted this simple idea into the public consciousness in many countries, leading millions to weather-strip their windows and add insulation to their walls and roofs. Partly as a result, home heating became 25 percent more efficient between 1973 and 1988 in Europe and Japan, and 45 percent more efficient in the United States. Adding insulation is still one of the most cost-effective ways for people to reduce the environmental impact of existing homes.

Many builders have discovered that designing from the ground up for air tightness and thermal integrity can reduce energy use even more dramatically. During the past decade, roughly 100,000 "superinsulated" homes with extra-thick insulation and careful construction to block air leaks have been built in Scandinavia and North America. So hermetic are these homes that just the warmth radiating from people, lights, and appliances goes a long way toward heating the interiors in cold weather.

New technologies are also revolutionizing windows, which are often the leakiest parts of buildings. Advanced windows with two or three panes of glass separated by thin, insulating layers of argon gas are becoming increasingly popular. Some of the windows are manufactured with chemical coatings that allow visible light to pass but block infrared radiation, which transmits heat.

Just since 1984, advanced windows have claimed 38 percent of the residential market in the United States. This shift now saves homeowners some $5 billion in energy bills each year. Not only can advanced windows insulate some six times as well as traditional single-pane glazings, but by admitting sunlight, they can actually capture more energy than they lose. (Some glazing companies are even integrating solar cells into windows which provide filtered light while generating electricity.)

The basic principles of solar architecture can be traced back at least as far as the ancient Greeks, who turned to the sun for their heat when fuelwood became scarce. Though they lacked glass for windows, the Greeks built many of their buildings with large south-facing openings. These portals captured rays from the sun in winter, when it rode low in the sky--exactly when it was most needed. But during the summer, when the sun climbed high overhead, much less light would enter inside. Today's passive solar homes work even better because advanced windows admit sunlight but trap the internal heat that it generates.

Some designers also exploit a technique known as daylighting, that supplants artificial light with sunlight by employing selectively glazed windows, skylights, and atria. Steven Ternoey, a Colorado-based daylighting pioneer, notes that "even with advanced lighting technologies, nothing is more efficient or more pleasing to the eye than using natural light to illuminate a building space." Top executives in one Chicago skyscraper vie not for window offices but for rooms fronting onto one of three daylit atriums.

In hotter climates, the design challenge is not making the most of solar heat, but getting rid of it--and builders use a variety of passive techniques to do this as well. In Hyderabad, Pakistan, many homes are topped with air scoops that face the prevailing winds and draw the air down to circulate through each story. Traditional house design in the southern United States endowed homes with generous porches to give people a place to sit in the long summer evenings, protected from the sun but exposed to the cooling breezes.

Other practices can also make buildings cooler. Light-colored roofing and cladding materials that reflect sunlight, for example, can cut peak cooling needs by as much as 40 percent in hot climates. Studies also suggest that planting trees around today's buildings could cut cooling needs by 30 percent. With nearly perfect timing, deciduous trees sprout shade-giving leaves before summer but then drop them before winter, letting the sun pass unimpeded.

MACHINES FOR LIVING

Although environmentally concerned designers always seek first to minimize the need for electrical and mechanical systems, it is almost impossible to provide all of the modern amenities often expected of a building without them. Just as important, since existing buildings cannot be fully redesigned, most of the improvements that can be made to them lie in improving the technological add-ons like heaters and lights and plumbing fixtures. Thus the challenge in every modern building is to close the gap between the climate that it naturally generates and the one people expect--with a minimum of environmental damage. The end result will be buildings that are more pleasing and more productive for their inhabitants.

Over the decades, developments in lighting have repeatedly demonstrated that new technologies can lead to dramatic improvements in a building's efficiency and livability. Incandescent lamps are over 10 times as efficient as oil lamps; they are more convenient, and provide better light. The light bulb-replacing compact fluorescent lamp (CFL) has risen spectacularly since it first appeared in 1982, and has captured 15 percent of the market from its technological predecessor. In Japan, where electricity is expensive, savings can reach $40 per bulb; not surprisingly, CFLs now fill 80 percent of the country's home fixtures.

Likewise, household appliances such as furnaces, toilets, and air conditioners have all improved markedly in recent years, and the additional savings potential remains large, more than covering the sometimes higher up-front costs. For example, electricity use in new U.S. refrigerators fell roughly by half between 1972 and 1992, thanks to better insulation, more-efficient electric motors, and other modest improvements. Some 1994 models use 30 to 50 percent less still. Other technologies likely to enter the market during the next decade could cut total appliance energy and water use by another 25 percent or more.

In buildings where cooling is a big energy consumer, every one of these improvements will carry an extra financial bonus, since the less power a machine consumes, the less heat it generates. In new buildings, engineers will be able to specify smaller air conditioning systems, which will cut capital and operating costs.

Energy-efficient buildings often have more usable space. When the cooling needs of a building are reduced, the need for air-handling ducts and blowers can also be reduced, allowing designers to downsize the hidden, wasted space between floors. So much space can be saved that for each four stories in a highly efficient structure, a fifth one can be added--meaning that less land is disturbed to provide housing for a given population.

As designers push the technological limits of efficiency, buildings function less like boxes full of separate kinds of machinery, and more like integrated organisms. For example, one way to reduce water consumption dramatically is to simply reroute "gray water" from sinks and baths to toilets. Likewise, it becomes easier to supply hot water or electricity by using sunlight.

At the same time, the advent of more highly integrated structures has brought new kinds of problems--such as the now-familiar concern that super-tight construction and superinsulation can cut heating and cooling needs at the expense of fresh air infiltration. To prevent this side-effect, most superinsulated homes use heat exchanging ventilators that automatically transfer heat from the exhaust to the cool incoming air, assuring a fresh air supply while minimizing heat loss. In designing healthy buildings, it is best to ensure adequate ventilation and to prevent internal sources of pollution.

As an added bonus, research shows that features like daylighting and high quality indoor air make employees more productive, and more likely to show up for work. In a typical office, employees' salaries cost roughly 70 times as much as the total energy bills. Boosting worker productivity just 2 percent, therefore, will save a company more than eliminating its utility bills entirely. So while a new Lockheed Corporation facility in Sunnyvale, California, uses daylighting and other efficiency features to cut lighting bills by 75 percent, what pleases the management most is that the higher quality lighting has reportedly led to an unanticipated 15 percent increase in productivity.

MAKING BETTER BUILDINGS

While the making of better buildings is a problem that must ultimately be solved by the makers themselves, governments are taking a variety of approaches to spur progress. In most industrialized countries, building codes and appliance standards stipulate minimum levels of performance, and these are beginning to catch on in developing countries like Thailand and Singapore. In the United Kingdom, government-sponsored rating systems help educate consumers about the invisible environmental impacts of their buying choices, and are quickly increasing awareness of these issues among builders. Taxes on resource depletion and pollution, though less common than subsidies for efficiency, can help market prices reflect products' ecological prices, making unhealthy building practices seem as expensive to builders as it is to society as a whole.

Government policy, new technologies, and cultural changes within the building industry--all can help reduce the environmental impact of buildings. But progress is threatened by countervailing economic and social trends. Perhaps a billion people now live and work in modern, western-style buildings. If rapid economic and population growth continues in the developing world, such buildings will house many billions more, multiplying several-fold the environmental impact of the global building stock. It is crucial, therefore, that developing countries take advantage of the lessons learned in the industrialized countries, and avoid their economic and environmental mistakes.

Growth in the building stock of affluent countries also threatens the sustainability of the industry. Consumer-oriented values have fostered a steady growth in home size for fifty years, literally pushing neighbors apart from one another, and insulating people from the natural world around them. Reversing this trend will require a shift away from materialism and towards a culture that values connection--among people and between people and the environment. This process may take a generation or more.

Fortunately, buildings themselves can be part of the solution. As Winston Churchill said, "We shape our dwellings, and afterwards our dwellings shape our lives." Buildings can bring people closer to their surroundings and to the natural systems that sustain life. They can help people to make the psychological connections necessary for building a sustainable society.

William McDonough, dean of the University of Virginia architecture school, has designed a German daycare center that illustrates this point well. A skylight would run the length of the building, providing much of its heat and light, and allowing children to follow the sun as it crosses the sky each day. If the building overheated or nap time came, the children themselves would be able to pull shutters across the windows, in effect "putting the building to sleep." Thus the building's design is fundamentally educational. It would teach young people to appreciate what most builders have forgotten: the relationship between the built environment and the natural one.

David Malin Roodman is a staff researcher and Nicholas Lenssen is a senior researcher at the Worldwatch Institute. They are co-authoring a chapter, "Making Better Buildings," for the forthcoming State of the World 1995.