The draping concrete roof protects the interior from the hot Florida sun.
Drone Permission The draping concrete roof protects the interior from the hot Florida sun.

Reinforced Structures, Inc. (RSI) recently completed the concrete work on the Thomas P. Murphy Design Studio on the campus of the University of Miami School of Architecture. RSI provided a turnkey concrete package for the building, including the dramatic, curved concrete roof over the 20,000 square foot, open-plan building. The roof looks melted by the Florida heat, but is actually twelve-inch thick concrete that gracefully drapes over the main entrance and sides and serves as a shade from the relentless Florida sun. The overhanging roof minimizes direct sunlight, creating an energy efficient structure, but because of floor-to-ceiling windows, the building requires little interior lighting, further increasing energy efficiency.

“It’s not a big building so it was all hand-set,” says RSI, vice president Hogan Herges. “We used shoring to create a deck on the draped parts then did a lot of false work and used foam to create the drape. Layout was the trickiest part, shooting the elevations to make sure the falsework on top of the flat deck portion was going to make the thing look appropriate. It was a single pour and a stiff mix so we had to use superplasticizer to pump it but then used accelerators to make the concrete stiffen along the edges so that it didn’t just ooze over the edge.”

The concrete roof slab is exposed on the building’s interior. “We took extra care to butt the joints together on the plywood and then the guys caulked all the joints at the exposed edges of the plywood,” says Herges, “so it looks like as-cast concrete but you don’t see the ooze at the joints that you typically would on a blow and go deck.”

Getting the exposed architectural concrete walls to have a consistent color and texture was also tricky, especially with the board-formed surfaces that they achieved using rough-hewn cedar linings. “There was a little bit of water that discolored the concrete and created some darker areas where we tried to touch them up a bit, but pretty minimal. When we first stripped we thought it was a little non-uniform but the architect liked the natural look of it and it settled down into a more uniform color.”

The Thomas P. Murphy Design Studio was named after the late father of the president of the project’s general contractor, Coastal Construction Group, Miami. “The teamwork was really good,” Herges stated. “They had a great superintendent on the project and the architect was also good to work with. We got involved very early when they only had conceptual sketches, pencil drawings to try to figure out what they were after. One of the first things they showed us was literally a shoe box with a piece of paper draped over it.”

RSI’s three partners are (left to right) Hogan Herges, vice president; Steve Whitley, CEO; and Miguel Tellez, president.
RSI’s three partners are (left to right) Hogan Herges, vice president; Steve Whitley, CEO; and Miguel Tellez, president.

Architectural concrete is a specialty for RSI, having also worked on the Dali Museum in St. Petersburg. “We’re a turnkey sub and self-perform most of our work from excavation to finishing,” says Herges. “Our sweet spot is post-tensioned midrise to high-rise structures and there’s a ton of it right now. And then we tackle this sort of thing when it comes long. It’s tough to get an appropriate mark-up for architectural concrete work because it’s pretty risky and the margins are not what we think they should be but we still like to these projects when they come around.”

Steve Whitely is the CEO of RSI but there are three partners, including Herges and president Miguel Tellez. Herges explains that RSI works only in Florida and is based in St. Petersburg. “There’s plenty to do within the state both in the Tampa area and down to Sarasota and in South Florida. We have 405 tradespeople and a management staff of 115.”

Herges notes that RSI tends to lease equipment more than buy. “That’s Steve’s philosophy. Unless you’re always really busy it’s hard to keep that stuff busy and you have to have the ability to transport it and maintain it. So we lease most of our equipment. We do have a lot of formwork and tend to use Shore/Form Systems and Aluma.”