LOUISVILLE, Ky. (WDRB) -- The old expression “cleaning up city hall” is getting a whole new meaning in downtown Louisville, where the building is undergoing an extensive restoration.

The man in charge of the project says it's been so long since the building got a major scrubbing, there's no official record of it.

City Hall was dedicated in 1871, and opened in 1873, just 80 years after the death of King Louis the 16th of France, for whom Louisville is named.

“Over the years, there's been a lot of carbon, biological buildup on the building from years of pollution,” said Mark Zoeller, assistant director of facilities and project management for metro government.

Metro Council approved a $4.8 million project to carefully clean and restore the building, which was constructed using Limestone.

“Limestone can be somewhat fragile, so you have to be very specific about what pressures you use, the hot water that you're using and on the cleaners,” Zoeller said.

The restoration job is both labor-intensive and tedious, which is why most of the building is cocooned in scaffolding.

“It's an environmentally friendly cleaner that they put on," Zoeller said. "It soaks for a couple of hours, and then they actually hand scrub every inch of City Hall."

At the same time, crews are also working across the street on Metro Hall, the old county courthouse.

“Metro Hall,  probably from the time it was constructed, wicked water, and they applied a plaster material. That has failed over the years,” Zoeller said.

So the building is being resurfaced and light fixtures restored. One fixture on the corner of the building was found in pieces stored inside Louisville Gardens. It is now rewired and back in place.

“We're talking about two jewels in the crown of Metro Louisville in City Hall and Metro Hall,” Zoeller said.

Jewels that will soon shine more brightly when years of neglect are scrubbed away.

“We're not going to be able to get every bit that off City Hall," Zoeller said. "Some of it is just too encrusted. But we'll be able to make a great improvement to the appearance of City Hall.”

The makeover includes new energy-efficient windows for City Hall. The project should be finished by the end of the year.

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