Blaine Brownell, Material Strategies: Innovative Applications in Architecture ($24.95, Princeton Architectural Press, December 2011)
The excerpt below is taken from the chapter “Mineral.” It has been copyedited to match ARCHITECT’s house style.
Earthen minerals were some of the first materials that early hominids used to make shelter and tools. Many ancient myths and religions associated earth and stone with human flesh and bone, respectively—minerals of varying consistency were seen as symbolically connected to the body and its dual characteristics of suppleness and fortitude. Archaeological records indicate active manipulation of stone during the prehistoric period known as the Stone Age, which accounted for more than 99 percent of human existence. The transition from the Stone Age into the Copper and Bronze ages roughly marks the beginning of recorded history.
Loam, stone, and ceramics—the primary materials considered in this chapter—were fundamental to the genesis of civilization, and they gave physical form and order to the first cities. Because of their compressive strength, these materials were appropriate for the thick-walled, low-slung structures that emerged as layers of earth were laid and compacted to make the first load-bearing walls. For millennia this striated architecture signified weight, presence, and longevity.
Today the use of the load-bearing wall has all but disappeared in industrialized nations and has been replaced by frame construction with applied skins. The persistence of earthen materials in contemporary building despite this transformation is a testament to their powerful legacy. The current applications of stone and brick are generally suspended or self-supporting surfaces over skeletal frames—a perverse transformation from their original use. However, both the broad availability of many mineral resources and the perseverance of stone and ceramics as architectural membranes suggest continued importance of earthen materials in building construction.
Earthen materials were critical to the origins of technology. The development of stone tools and pottery, as well as the construction of early shelters, occurred during the Stone Age (2.9 million years ago–6500 BCE), the first human epoch. Megalithic monuments, such as stone circles, dolmens, and cairns, constructed of large, regularly shaped stones are enduring reminders of tombs and sacred sites of the period—Stonehenge (3100–1600 BCE) being the most familiar example.
The first stepped pyramid, the Pyramid of Djoser, was built in Egypt around 2600 BCE for Pharaoh Djoser. Imhotep, considered to be the first architect, designed and oversaw the pyramid’s construction and used rough-cut Tura limestone blocks for the enclosure wall, colonnaded entrance, and pyramid. The use of limestone was a much more durable alternative to the use of mud brick, a material common to early Nile River–valley societies and an expedient resource for settlement building, also used in earlier Egyptian tombs.
Djoser exhibits one of the first known uses of the architectural column. The colonnade at the Pyramid of Djoser consists of pillars carved to resemble bundled plants—one of the first instances of architectural transubstantiation of wood into stone. The Greeks continued this approach, developing proportion-based systems and techniques that transformed stone used in building from coarse blocks into refined, specialized modules resembling abstracted components of trees and plants.
The Greeks also further developed ceramic materials—which offer good compressive strength and moisture resistance—from the early pottery-based tiles and fired bricks used in Egypt and Mesopotamia (as early as 4000 BCE) to modular building elements such as roof tiles designed to overlap like fish scales to direct the flow of water (800 BCE). (The word ceramics derives from the Greek word keramos, meaning fired earth.) The Romans further augmented ceramic technologies in their extensive use of brick, which was often applied to walls of concrete.
Stone technology achieved its apex during the Middle Ages with the construction of soaring Gothic churches. Stonemasons developed increasingly sophisticated vaulting and buttressing technology that allowed stone to reach unprecedented heights, conveying an uncanny lightness and delicacy despite its heavy weight. Although later industrialization enabled greater control in the manufacturing and distribution of stone and ceramics, the arrival of frame construction in the 19th century rendered the load-bearing application of these materials obsolete.
Despite the change in load-management practices, stone and ceramics are still widely used. After the ascendance of steel, concrete, and wood-stud framing systems during the 19th century, earthen materials were applied in veneer form—layered with other materials to create architectural surfaces with durability and presence. Antonio Gaudí’s constructions of elaborate mosaics using broken clay tiles (called trencadís) are exuberant examples of these types of embellished surfaces. Adolf Loos’s use of highly figured Cipollino marble in the façade of his Loos House (1910) in Vienna achieves a flamboyance with the material itself. Adhering to precise geometries, the tile cladding on Jørn Utzon’s Sydney Opera House (1973) roof shells is another example of the maturation of earthen veneers.
For Uruguayan engineer Eladio Dieste, brick had a more significant role than as decorative veneer. He selected the material as the primary building block for his Church of Christ the Worker (1960) in Atlántida, Uruguay, precisely because it was more familiar to the local farmers than stucco or stone. Dieste explored the little-known structural potential of reinforced masonry in the church, transforming hand-laid brick walls into structural shells. The plan of the one-room church is elementary at ground level, but the wall contours change with altitude from rectilinear lines at the base to sinusoidal waves at the top. Composed of impossibly thin brick shells, the walls were constructed without joints to be a single undulating unit like the roof. Dieste demonstrated that a humble veneer material could exhibit the structural and geometrical sophistication of thin-shell concrete structures.
While Dieste’s church explores structural lightness with brick, the Beinecke Rare Book and Manuscript Library (1963) in New Haven, Conn., achieves visual lightness with stone. In his design for the building, Gordon Bunshaft of SOM substituted conventional glazing with translucent stone—both to convey a sense of gravitas as well as protect the rare books held within. The façade consists of a Vierendeel frame clad in Vermont Woodbury granite on the exterior and precast concrete on the interior; the frame holds translucent white Vermont Montclair Danby marble panels in place. During daytime the 1-1/4-inch- (3.18cm-) thick marble panes appear stark and opaque on the exterior, while sunlight highlights the deep, richly colored veining of the stone from inside. At night the relationship is reversed, transforming the enclosure into a softly glowing lantern.
Peter Zumthor’s Therme Vals project (1996) exploits the power of stone to create immersive, enduring spaces. Located in a remote village in Graubu¨nden, Switzerland, the thermal-baths structure conjures the image of a rock quarry, and its simple, rectilinear geometries made of many thin layers of stone contrast abruptly with the landscape. Zumthor minimized the material palette to highlight the basic architectural elements of stone, water, and light in the building. The concrete structure is faced with 3-foot-3-inch-(1m-) long slabs of local Valser quartzite stone. The approximately 60,000 slabs cut in three different heights (the three dimensions of each slab add up to approximately 6 inches [15 cm]) create an irregular rhythm while maintaining a regular module overall. Interior spaces convey a brooding atmosphere reminiscent of water-filled caverns. A grass-covered roof completes the impression of an excavated site, rendering the Therme Vals as a modern cairn that is as ageless as it is shrewdly contemporary.