Concrete is a diverse structural and design element for modern home building. In the past 10 years the Arts and Crafts movement has enjoyed a resurgence of popularity, and is being used in the design of concrete elements inside of homes. Contractors and architects have been able to take the comfort, warmth, and fine craftsmanship shown in the simple, clean lines of this style and apply it to concrete walls. In some cases, the contractors are even incorporating more creative methods, such as leaving exposed beams, nail holes or luminous effects, in order to balance a natural concrete look indoors and out.
"The site was like entering another world-a wooded hillside along the river bank with distinctive steep rock canyon walls," says David Hyman, Deca Architecture, Portland, Ore. "I felt a responsibility to respect the spectacular quality of the site and to create a house that linked the land with the river. The canyon rock was the inspiration for creating the exposed concrete wall, which travels from outside the front door through the house and out onto the back deck."
The home's battered concrete wall is thicker at the bottom and tapered toward the top and includes formed niches and window openings. The taper emphasizes triangular shadow lines similar to a riverbank. Structurally, it became a shear wall that supports the floor above and allows the rest of the structure to be lighter. However the snap ties posed a challenge for the contractor.
"The snap ties had to be specially made in decreasing sizes to accommodate the taper," says Chuck Gervovitz, Gervovitz Construction, Vancouver, British Columbia, Canada. "There was a cone on both sides. In most applications those holes are plugged, but in this one, they were left void and became a decorative feature." The entire wall-which is 16 inches thick at the base and 6 inches at the top-was placed at one time using a 7000 psi compressive strength pea gravel mix pumped through a 2 inch line. Formliners made from sheets of 4x8-foot plastic with wood grain in a raised texture were placed inside the forms, which also provided the texture for the 16-inch-square support columns. The wall and columns were left natural with no added color, stain, or sealer. "I wanted the color and design to enhance the natural concrete and to play the cool gray color against the warm wood," says Hyman. All the materials in the house were treated to bring out their natural qualities-the flooring of carbonized bamboo, the beams of fir, and even the plaster of the fireplace. "The owners worried about the unfinished voids from the snap ties and that the concrete would be a cold material, but in the end they are glad they did it," says Hyman.
Minneapolis: A Reflective Precast Panel.
Charles Stinson, architect, Charles R Stinson Architects, Deephaven, Minn., and Thomas Schrunk, artist in Lustrous Materials, Minneapolis, collaborated to produce unique precast panels for a home featured in the Minneapolis Luxury Home Tour. The concrete panels in the home are defined as anisotropic, or lustrous. "Most often, light hits material and bounces off equally in all directions in a 180 degree dispersion, or isotropic," says Schrunk. "But in an anisotropic application, light reflects stronger in one direction than another. In this application when you walk up the stairs the luster changes as the light hits the ridges and grooves. Light areas become dark and dark areas become light."
Schrunk first made the mold with its light-specific design texture. Next, the mold was cast into 12 panels that are 1 meter square and 3 inches thick using white portland cement. The panels stack on one another and attach to a stud wall that rests on a poured concrete foundation. "Stinson's interest in natural materials and my use of light-responsive surface textures combined in concrete panels. The repetitive imagery unconsciously reflected my appreciation of that aesthetic in Frank Lloyd Wright's work," says Schrunk.