Downtown Dallas' landmark Davis Building is getting another redo.

The 20-story Main Street tower, built in 1926 as the headquarters for Republic National Bank, was converted to apartments in 2003.

Last year, Dallas oilman and investor Tim Headington bought the historic high-rise to add to his holdings in downtown Dallas. Now the Davis Building is getting a $45 million reboot.

Mycon Construction says it's been hired to renovate the 250,000-square-foot residential and retail building at 1309 Main St. over the next 15 months.

"We are honored to be part of the project team working on revitalizing this historic building in the heart of downtown Dallas," Mycon's vice president, Scott Pitt, said in a prepared statement. "We are also working in a space that will remain occupied during construction."

Dallas architect 5G Studio Collaborative — the same designer who did downtown's Omni Hotel — is the project architect.

The renovation includes upgrades to the retail space in the building and conversion of the 183 loft-style apartments into 215 luxury rental units.

The Davis Building, which sat vacant for almost 20 years, was one of the first downtown office buildings converted to apartments.

Headington owns multiple Main Street properties including the Joule Hotel and the just-opened Forty Five Ten retail building.

Headington is spending more money to upgrade the Davis Building than the estimated $35 million developers spent to renovate the old office property 15 years ago.