Lauth Property Group has begun erecting the steel for the 20-story NASCAR Plaza office tower next to the planned NASCAR Hall of Fame uptown on Caldwell Street.
Company officials said construction of the first floor will take about five weeks, but after that the building will rise at the rate of a floor a week.
The 390,000-square-foot "green" building is to open in March 2009, about a year ahead of the NASCAR museum.
The office building is poised to be the first one occupied among more than a half dozen new office projects under way in the center city.
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NASCAR Images and NASCAR Licenses will occupy about a third of the space. The rest is available for lease.