The renovation plan has been in the works conceptually for several years, and in May was assigned to California shopping center developer The Festival Cos. for implementation.

Initial plans called for softening the center's bunkerlike appearance by applying new exterior finishes similar to the kapa patterns outside the Cheesecake Factory, and reducing three thick concrete bridges connecting mall wings to a single, less-dense bridge that opens a view to the Royal Hawaiian hotel.

More landscaping and transforming the mall's central performance area into a grovelike setting was also part of the early redesign of the four-story complex, which opened in 1981 and has long been criticized as a poorly designed concrete-paneled fortress.

New enhancements announced yesterday include "opening up" the center by adding more windows and lanais. Upper-level flooring will be upgraded. A nine-restaurant food court will be added to the second floor, and third-floor restaurants will receive dedicated escalators and elevators to improve access.

Partly because of the planning changes, the construction timetable has been pushed back by about six months. Work is now expected to begin in mid-April and be finished in July 2006.

The 293,000-square-foot mall has struggled over the last several years, with recent vacancies as high as 40 percent, though Kamehameha Schools has said the mall is profitable. A few new tenants were added to the property earlier this year, and third-quarter sales rose 19 percent, the trust said.

Kamehameha Schools expects that most new retailers and restaurants — a mix of national retailers, theme restaurants and local tenants — will be open upon completion of the revitalization project.