The new Allegheny branch of the Carnegie Library throws its grand opening party today, a free, public event from 10 a.m. to 2 p.m.

The system's newest library, at 1230 Federal St. in the Central North Side, opened two weeks ago without fanfare so staff could get used to the space and resolve early problems.

The $6 million project is only the second new construction in the library system's capital campaign to retrofit or build spaces for maximum efficiency of use and energy.

The new library, a one-story building of two-story height, is awash in natural light, with slatted wood along the front and an enclosed outdoor patio for children. The children's section is almost half the building, with elephant-shaped stools and a play area.

The Allegheny City Historic Reading Room will grow to include contributions from Allegheny City Society members, said Carlton Stout, the branch manager. The library also will have community meeting space.

"We're so happy to have our neighborhood library back," said Alida Baker, director of the Allegheny Commons park restoration project. "I'm looking forward to meeting there."

The library sits on the site of a former gas station. It is flanked by casual restaurants and a raft of new townhouses in the Federal Hill project, of which three are already occupied.

The former library, an historic landmark in Allegheny Center, was damaged by a lightning strike three years ago and deemed unfit for the library's future purposes. It is still being used for auxiliary purposes.

Dr. Barbara K. Mistick, president and director of the Carnegie Library system, will speak after a 10:15 a.m. ribbon-cutting. Other scheduled speakers are Mayor Luke Ravenstahl, City Councilwoman Tonya Payne, state Sen. Jim Ferlo, D-Highland Park, and state Sen. Wayne Fontana, D-Brookline.

The event will feature performances by the Hip-Hop on L.O.C.K. Project at 9:45 a.m.; music and storytime with Sheri Van Dyke from WWWS-FM 94.5 at 10:45 a.m.; the Ortner-Roberts Duo at 11:30 a.m.; storytime with Amir Rashidd at noon and the Pittsburgh Musical Theater 1:00 p.m.