New Harmony, Indiana's Roofless Church has been an area landmark since its dedication in 1960. Designed by architect Philip Johnson, it's an open park enclosed by a brick wall that's especially popular as a venue for weddings.

Despite its name, the church is not quite roofless. The altar is sheltered by a 30-foot-wide by 50-foot-tall wood-framed dome that's as much abstract sculpture as building, with a flowing, six-lobed form that resembles a draped sheet of cloth. After a half-century of exposure to the elements, the original cedar-shake roof was badly deteriorated, and it fell to local builder Jeff Koester to replace it.

Dealing with the compound curves of the surface presented some obvious challenges, but according to Koester, the crew caught a couple of lucky breaks (see slideshow). Although many of the existing shakes were falling to pieces - particularly near the peak, where the angle flattened out - the laminated plywood sheathing underneath was in excellent condition. "It must have been laminated on the site somehow," Koester says, "but I have no idea how they did it." The 1/2-inch plywood nailing strips that provided a ventilation space between shakes and sheathing hadn't fared quite as well but were still largely intact. Where necessary, they were replaced with strips of PT plywood.

Because the quality of hand-split shakes has fallen over the decades, red cedar shingles were specified for the new roof. ("The shakes you get now are awful," Koester says, "mostly second growth. You can't get them to lie flat!") Installing the shingles would be tricky; as with the original shakes, the exposure of each successive course needed to decrease slightly - but not consistently - from the bottom of the structure to the top, to accommodate the structure's unique shape. Here, too, luck was on Koester's side: Johnson's surviving original drawings specified the required exposure for each individual course to the quarter inch.

Armed with those drawings, Koester's two-man crew used a boom lift to work their way methodically up the structure, tearing off the old shakes and shaping and hand-nailing the new shingles - a task that began in late August and ended just before Christmas. The first wedding under the new roof is expected to take place this month.