Refined Design at Clear Lake

Hospital Adds Two Floors After Fourth Level Complete

By Lesley Hensell

When it seemed there was no good way to make room for new patients, Clear Lake Regional Medical Center charted a roundabout path for growth.

The Houston-area hospital struggled to find an effective method for expanding its round-shaped, 35-year-old facility. Tying in the existing building's circular shape would make new construction difficult, so the hospital instead launched plans to centralize cardiac care in a new heart hospital.

Construction began in July 2005 on the $90 million heart hospital, which will be connected to the medical center by a pedestrian bridge. With approximately 84 beds, the heart hospital will increase the campus' capacity to 454 beds and will house operating rooms, intensive care beds, a coronary care unit, catheterization laboratories and private inpatient beds. To help the new heart hospital tie visually with the existing round hospital, the rectangular building features a rounded glass curtain wall in the front, said Mark Roan, an associate at the Dallas office of architecture firm Perkins + Will.

The two buildings are connected by a 400-ft. pedestrian bridge over a busy county road. With roughly 100 tons of steel, the bridge was assembled primarily on the ground in modular sections. Once those sections were ready, the street was closed down so that they could be lifted into place.

"Probably one of the more challenging parts of the project was the connector bridge itself, with all of the restrictions and entities we had to coordinate through," Roan said. "We also were tying into an existing building with set floor-to-floor heights." The air-conditioned bridge has been finished off with metal panels and glass, while the heart hospital's skin includes a combination of glass, masonry, stucco and metal panels, said Troy Ireland, project manager for Austin-based DPR Construction, the general contractor.

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Extra care had to be taken at the project's outset due to the sandy, unstable soil on the seven-acre site.

"We did some massive excavation to get the footings done about 8 to 11 ft. below grade," Ireland said.

When ground first broke, the hospital intended to construct a facility of 160,000 sq. ft. over four stories. But months into the construction process, the hospital exercised its option to add another two floors to the project, bringing the total square footage to 210,000, Ireland said.

"Our original goal was to finish the concrete structure on March 15 of '06," Ireland said. "The hospital had always intended on future vertical expansion, but around December, we got the word that they were ready to go ahead and pull the trigger while we were here. We incorporated the added work and completed the structure for all six floors just two weeks after our original deadline."

The additional floors also required slightly different specifications, which created an even greater time crunch, Ireland said. The project is slated for completion in March 2007, although the top two floors will not be finished out until a later date.

"We are close to the bay, where there are a lot of sandy soils," Ireland said. "Based on the site's soil-bearing capacity, when the two floors were added, we could only do so much in concrete, with the rest in steel. Concrete goes quicker than steel does."

The architect chose cast-in-place concrete for the building's structure for several reasons, Roan said.

"The symmetrical shape of the building and the uniformity of the column bay distances allowed for a lot of repetitive form use, which led us toward concrete" Roan said. "We could have built it out of steel, but the lead times were simply too long. Concrete and the labor needed to get it in place were more readily available."

To ensure that the cast-in-place structure's 6,000 yds. of concrete were quickly poured, subcontractors had about 70 workers onsite up to six days a week, Ireland said.

"We were fairly fortunate that while we were working on most of the structure, we didn't get a ton of rain," he added. "We lost about two weeks during Hurricane Rita last year. We have not seen problems with material shortages."

During the cast-in-place concrete portion of the project, a four-story tower crane was installed on the site.

"When we were told that the additional two stories would be going up, we spent a weekend lifting the crane 30 ft. to accommodate them," Ireland said. "There was a scramble to get the equipment in place quickly, so we could stay on track."

For the cast-in-place work, the team used a Peri Formwork System for pours of about 15,000 sq. ft. each.

"We tried to do about a pour a week," Ireland said. "With that fast pace, we had a lot of questions that had to be resolved with the structural engineer on the fly."

The addition of two floors also meant that the building would be considered a high-rise and under different building codes.

"The added floors put us into a higher wind-load bracket, since we are close to the coast and have to allow for hurricane-force winds," Ireland said. "This has affected the design of exterior framing systems, as well as the glazing system. There are now an entirely new set of safety rules in place."