When it opened more than 40 years ago, Medical Towers North was a distinctive new presence on Louisville's skyline.

As the city's first "curtain wall" building, its bright blue porcelain-covered exterior panels, hanging from an aluminum grid on the eight-story structure, added "a note of cheer to the otherwise drab surrounding area," a 1963 advertisement said.

The ad praised modern features including air conditioning and a parking garage that could double as a fallout shelter. But today the medical office building at Floyd and Gray streets is out of date, and its owner, Norton Healthcare, is taking it down so a modern replacement can be built.

The demolition poses special challenges because the building is surrounded by hospitals, meaning Norton must remove the structure without spewing dust and mold around the downtown medical center.

And there can't be falling debris because of the many people who walk or drive past the busy medical corner of Floyd and Gray every day.

In addition, the job must be done without the vibration that would be caused by conventional demolition techniques, because the building's foundation is only a few inches from Norton Hospital's surgery suites. The operating rooms stretch underground about half a block from the hospital's above-ground footprint, butting up against the basement of Medical Towers North.

"Surgeons don't like vibration. A lot of them are doing some really delicate work," said Shawn Brinley, president of HCL Inc., contractor for the demolition.

For those reasons, the project is destruction with a gentle touch.
Norton put together a game plan that includes vibration detectors, daily air sampling and erecting a 42,000-square-foot black screen around Medical Towers North.

Louisville-based Micro-Analytics supplied vibration-detecting equipment and services, while Environmental Safety Technologies, also of Louisville, is doing the air sampling to gauge levels of dust particles and mold that might be stirred up.

"The goal of the project is to minimize the dust