Moisture is no stranger to the South. And as in many cities with humid climates, building owners in Baton Rouge, with its large-scale plans to improve the downtown business district, are taking a hard look at the need for quality waterproofing. Of all the issues that need to be handled each day in a government office building in the central downtown area, water intrusion is not one that is welcome.

One of the newest buildings in downtown Baton Rouge, the Iberville Building is located at the gateway of the Louisiana State Capitol building. The building is part of the Capitol Complex Campus for the state of Louisiana, which houses statewide offices and includes 10 office buildings. With the Mississippi River just a short distance away, extra measures were needed to keep moisture out.

Constant water pressure would bear on the new building, so officials made plans to ensure that the building's waterproofing integrity wouldn't be an issue. “There used to be a 13-story building here,” said Don Brouillette, who has 25 years of below-grade waterproofing experience and is the owner of Don Brouillette and Associates in Baton Rouge. “We imploded the building and left the existing basement. We then began building the new basement inside the existing basement.”

With the area's average of more than 60 inches of rainfall a year, the Iberville Building, which houses the department of social services, administrative buildings, and print facilities had to be watertight. “It was like waterproofing a bathtub, but we wanted to keep the water out of the tub,” said Brouillette.

The concern over water intrusion into the nine-story building's interior led to strict specifications for this government project. “Carlisle Coatings and Waterproofing's (CCW) MiraCLAY membrane was chosen for this project for many reasons,” said Michael Holly, Holly & Smith Architects, APAC, an architectural firm in Hammond, La. “We are familiar with the system, and it has proven success. We like the involvement that CCW offers. It's as though we have eyes watching over the project, making sure everything goes as planned.”

MiraCLAY is a bentonite clay waterproofing membrane that prevents water intrusion in below-grade applications. Its impermeable composition worked especially well for this project due to its ability to self-seal punctures or penetrations. With a variety of construction workers at the jobsite and reinforcing steel being installed, this was a major benefit.

“It's easier to install than other waterproofing systems. It's like cutting butter,” said John Deare, a construction worker for Apex Waterproofing. “It's very light compared to what we were working with.”

With the 278,902-square-foot project scheduled to finish in April 2006, the initial steps of installing the Mira-CLAY did not prolong the construction. The system's uniform layer of sodium bentonite clay is between a durable puncture-resistant, non-woven polypropylene fabric and a high-tensile-strength woven polypropylene fabric that allows it to endure construction wear and tear. “The geotextile composition prevents it from deteriorating,” said Brouillette.

The fabric is needle-punched together with thousands of high-strength denier yarns. This fabric is then thermally fused to the polypropylene in a patented procedure that locks the sodium bentonite into place.

“We laid the MiraCLAY like a carpet,” said William Fey, a construction worker for Apex Waterproofing. “We installed it with a 4- to 6-inch lap seam. We then stapled the seams and placed rubber water stops where there are penetrations. The system won't allow any moisture to come from the ground into the basement.”