Downtown Nashville's third-largest private parking facility, Public Square Garage, sold for a whopping $54 million on Wednesday – nearly twice its 2015 value.

The 12-story above-ground building at 350 Deaderick Street should not be confused with Public Square Parking, a Metro-owned underground lot at the courthouse across the street.

Philadelphia-based Stoltz Real Estate Partners bought the site through its Nashville Garage LP entity. The seller was a joint venture between Nashville-based RBN Equities and an unnamed partner.

In 2015, the garage was valued at $26.2 million – up from $11.3 million in 2012.

CBRE Group, which listed the sale in April, said a growing parking shortage is buoying its value.

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"With only 20,000 parking spaces for more than 65,000 employees and an average of 35,000 other daily visitors, the central business district suffers from a severe parking shortage, which makes Public Square Garage a great investment," said Douglass Johnson, senior vice president at CBRE.

The downtown parking shortage isn't expected to clear up anytime soon, either. Four of five hotels under construction within two blocks of the garage have no on-site parking, according to CBRE officials.

The garage, built in 2004, has 1,069 spaces. A representative from Stoltz said the city's rapid growth prompted the investment, along with successes in past Nashville purchases.

Stoltz owns a 20-story office tower at 4th Avenue North and Church Street and The Stahlman apartment building on Second Avenue North.