Carved in stone
Rich in texture, diverse in color, durable and of the earth, stone possesses an inherent sense of solidity and strength that makes it a natural choice for institutional buildings. These characteristics, in addition to the cost of quarrying, finishing, transportation and construction, are reasons why government buildings, justice facilities, libraries and other public buildings are most often associated with its use.
Stone suppliers, fabricators and designers are cutting the material's cost through the use of computer-controlled quarry machinery, and by specifying natural stone indigenous to the region where it is used, reducing finishing and transportation costs.
"The trend is toward the use of natural, rustic materials," says Dorothy Kender, director of the Building Stone Institute, Purdys, N.Y., adding that in the aftermath of 9/11 security concerns have prompted selection of heavier materials. "People are getting back to basics," she says.
Two recent projects — the Indiana State Museum in Indianapolis and a dining hall at the University of the South in Sewanee, Tenn. — illustrate the innovative and affordable application of stone to provide institutional buildings with character reflective of their surroundings and their regions' environment and heritage.
Home-grown Hoosier stone
Appropriately, Indiana limestone supplied by Evans Limestone Co., Bedford, Ind., is the primary material adorning the exterior of the Indiana State Museum, which opened this spring.
The limestone product used most extensively on the project was a type known as rough-back — the natural cleft-finish broken face of the stone created during the quarrying process.
Rough-back limestone was chosen for its natural finish and texture (marks from quarry drills can be seen on individual pieces of stone), but also because the material was cost effective. "I don't know that this has ever been done before to this extent," says William Browne, president of locally based Ratio Architects, the project's designer. The rough backs cover most of the exterior of the 230,000-sq.-ft. building, and nearly all of the 300-ft.-wide by 64-ft.-tall south wall that includes its main entrance.
Once a plentiful byproduct of the quarrying process, rough backs are rarer today, thanks to modern stone-cutting techniques, says Frank Ira, Evans' head of sales and administration. "We had to find blocks of stone with rough backs, saw the rough backs off the block with a belt saw, stockpile them and then cut them to size with a rip-and-joint saw after we were given the dimensions," he says.
The main entrance of the Indiana State Museum is clad in limestone.
F.A. Wilhelm Construction Co., Indianapolis, was the museum's general contractor and its masonry group performed the masonry work. Because of the size and dimension of the building and the complex pattern in which the limestone was to be placed, John Hartlep, Ratio's project manager, says the masons were "called upon to be real craftsmen on this job."
Wilhelm arranged the rough backs in a modified random ashlar pattern so that neither vertical nor horizontal joints were continuous. The wall's mass necessitated the use of larger-than-typical stone sizes: 8-in., 12-in., 24-in., 36-in., 48-in., and 60-in.
The stone was mortar set with a urethane caulking sealant applied to relieving angles and control joints. Stainless-steel flashing was installed at relieving angles at the top of the walls and at the building's base.
To attach each piece of limestone to the building's steel frame, concrete masonry unit (CMU) or existing precast panel walls, the contractor together with Arsee Engineers, Fishers, Ind., designed special stainless-steel anchors.
Dining hall sparks quarry's rebirth
Though the multicolored sandstone of middle Tennessee may not be as familiar to some as Indiana limestone, it was easily recognizable to Malcolm Holzman, a principal with Hardy Holzman Pfeiffer Associates, New York, the firm selected to design the 43,000-sq.-ft. dining hall on the campus of the University of the South.
Holzman, an ardent proponent of the use of stone in building design, the recipient last year of the Building Stone Institute's first James Daniel Bybee Prize for a lifetime of work, and author of a new book, "Stonework," had worked with the material before.
The result of Holzman's selection as designer and subsequent workshops involving university faculty, staff and students was a gothic structure reflective of other prominent buildings on campus. The dining hall, which opened in spring 2001, includes two major dining spaces and a series of smaller ones, servery, kitchen, meeting rooms and support and administrative spaces.
Holzman was intrigued by the idea of a traditional main dining room — a 250-seat refectory — that reinforces the university's tradition of dining. "Most universities have gone to a more informal seating arrangement," he says.
Though Holzman regularly visits the quarries that he is considering using, in this case, Houston King, the campus stone mason, broached the idea of reopening a campus sandstone quarry that had been closed for nearly 20 years. "He said he had figured out a way to quarry the stone in large quantities from the ledges of the quarry," says Holzman.
In all, the campus quarry supplied 750 tons of sandstone for the project. Another 1,500 tons of sandstone came from nearby sources. The material was of varying size: 8 in. and 16 in. wide by 8 in. thick, and random lengths. The stone was finished with split and cut faces.
Sandstone at the university quarry is sawn for use on the dining hall project.
The most striking elements of the dining hall exterior are 13, 39-ft.-high sandstone buttresses capped by 9-ft.-4-in.-high, saw-cut limestone finials supplied by Gillis Quarries Ltd., Winnipeg, Canada. Brazos Masonry Inc., Waco, Texas, was the masonry contractor. The height of the columns required exacting work by the stone masons on the project, says Mackie Bounds, Brazos' president and CEO.
Construction of the 42 structural columns that support the dining hall's slate roof involved attaching each piece of sandstone to CMU using stainless-steel anchors. Copper flashing was used to prevent water intrusion at each of the seven different penetrating points where the columns passed through the roof.
Just as Ratio Architects did with the Indiana State Museum, Holzman had mock ups of the dining hall's sandstone wall, roof and curtain wall built before the start of construction. "We had the subcontractor, general contractor, owner and our building committee all look at the arrangement," says Holzman. "In doing so, a consensus was built early on. We do it on all our projects now." Sounds like another rock-solid tradition.