Twenty-five months from today, Charleston International Airport should have a whole new look.

The $189 million makeover of the aging passenger terminal will be substantially completed by Aug. 17, 2015.

That’s the completion date announced Tuesday by a Charleston County Aviation Auhtority committee.

Already under construction is a new rental car pavilion and the central energy plant. Starting next week, passengers will begin seeing work zone signs rising around the baggage claim area as crews begin work on a third luggage carousel.

Construction workers will also add six new gates and a consolidated security checkpoint while making numerous other cosmetic and structural changes. The project will change the face of the airport inside and out.

Tom Skinner, with the Austin-Hitt construction venture overseeing the work, laid out an ambitious schedule to meet the August 2015 deadline, with the caveat that projects within the month-to-month schedule weren’t set in stone.

Hardly any part of the terminal will be unaffected by the demolition and reconstruction.

As construction ramps up, the four inner lanes in front of the terminal will be closed for several months, possibly starting in January, and pathways will direct passengers through construction zones throughout the building.

The new rental car pavilion could be finished by May, when work will begin on renovating the space of the current rental car kiosks.

Several projects will be going on at once in different parts of the airport to minimize interference with passengers and the airlines serving the airport.

Still, airports director Sue Stevens expects not everyone to be happy.

“We are going to be a construction zone,” she said. “We are going to get complaints. We will do our best to stay ahead of them.”

The airport terminal redevelopment committee unanimously voted to accept the guaranteed maximum price, including contingency funds, of $159 million. Another $30 million will pay for administration, architects and program management.

Contingency funds were set aside to handle unknown costs once walls are torn apart and to move around offices and vendors.

While construction costs were cut, none of the core projects was affected.

“We feel like we have a first-class facility,” said Len Dillinger with Michael Baker Corp., the firm hired as program manager for the project.

The 28-year-old terminal is being overhauled and expanded to accommodate the growing number of passengers at South Carolina’s busiest airport and to improve security.

Reach Warren L. Wise at 937-5524 or twitter.com/warrenlancewise.