The Heldrich Hotel and Condos

Quick Facts

• 10”-thick panels weighed only 32 lbs./sq. ft.
• Lightweight precast saves $90,000 in material and labor
• Cladding replicates the look of stone
• CarbonCast facade made under license from AltusGroup, Inc.

CarbonCast Delivers High Style, Low Weight and More Sustainable Design

Owners of The Heldrich, a 250-room, $110 million hotel and conference center with retail and academic space plus luxury condominiums, desired a high-end, classical appearance that would attract users of all types to the facility. But using true stone on the façade as they suggested posed significant challenges—especially for the budget. Instead, designers chose lightweight CarbonCast Architectural Cladding to create the look of stone with more benefits, including cost efficiency.

“The owners’ intent was to use stone and brick on the exterior, but it didn’t fit into the budget or the construction timetable,” explains Timothy Cent, project manager for CMMI, Inc. “We suggested architectural precast concrete panels to provide the look of stone in a more economical manner. We’ve used precast concrete panels in other projects, but we’ve never used it in the innovative ways that were employed on this application.”

The CarbonCast Architectural Cladding panels use carbon-fiber grid as secondary reinforcement in the panel face, replacing conventional steel mesh. Because carbon fiber will not corrode and controls cracks better than steel mesh, the panels use significantly less concrete in the panel face, since there is no steel mesh to protect from the corrosive effects of wind-driven rain and ice.

The panels also were designed with EPS foam embedded in the interior for insulation. This contributed energy efficiency and made the panels more lightweight, Cent notes, since the insulation was lighter than the concrete that it replaced. Each inch of insulated panel cost only about half of what a solid-concrete panel would cost, so it created a cost savings, too.

Aesthetics

The panels were fabricated to a thickness of 10 in. to allow for deep reveals and articulation that would create the classical design the architects were seeking. The cost of casting these panels was nearly the same cost as for thinner and less dramatic 6-in. conventional precast panels, Cent notes.

Also noteworthy was the precast panels’ use of High’s recyclable Eco-Blast™ steel shot to achieve the final sandblasted finish. The shot is reused for each application, rather than using sand, which is contaminated after being used and must be disposed of.

Casting the 124 panels, 185 column covers and 84 spandrels produced no exceptional design challenges, and the erection went smoothly, Cent reports. “Precast concrete is a fairly adaptable material, which is one reason we use it as often as we do,” he says.

Lightweight Precast

The project represents the first large-scale application of CarbonCast cladding. The panels’ sizes would not have been able to be created with a 10-in. thickness using conventional precast, because the erection crane would not have been able to handle the considerably greater weight. With the lightweight panels, the crane size did not have to be increased nor the panel size reduced to erect them.

The thin-faced, back-ribbed concrete panels weighed only 32 lbs. per sq ft, about 70% less than conventional 10-in. precast concrete panels. “The lighter weight minimized crane requirements, preserved piece size and kept erection costs under control,” says Cent. Approximately $90,000 worth of perimeter steel and labor costs were saved by using the lighter panels.

The use of precast concrete also helped with the construction schedule, Cent notes. “We anticipated that the façade would be constructed in the winter, and we knew the precast concrete could continue to erect through bad winter. The fast erection time was a key benefit for the project, as erecting panels was much better than having workmen up on scaffolding.”

CarbonCast is a registered trademark of AltusGroup, Inc.

C-GRID is a registered trademark of Chomarat N.A.