Perpetual Savings Bank, the largest savings institution in the Washington area, last week bought a 160,000-square-foot office building in Tysons Corner, where it plans to relocate some of its revenue-generating operations over the next several years.

The building is at 1951 Kidwell Dr., near the intersection of routes 7 and 495.

The eight-story building, formerly the Entree Building, was bought for $19.5 million from J.B.G. Associates, a District partnership.

Perpetual plans to move its mortgage company into the new offices this year.

"We looked for about a year for a building that had access to the Beltway and a good vista," said Jim Pastore, a spokesman for Perpetual.

The company does not expect to do extensive renovations on the building, but will undertake "normal tenant improvement work," Pastore said.

Over the next five years, Perpetual plans to phase other operations into the building, including construction, commercial real estate, retail lending and investment management.

Perpetual Savings Bank has assets of $4.5 billion.

In other developments in commercial realty:

Licom Inc., a phone systems producer, leased 54,000 square feet at Parkview Executive Center, 593 Herndon Pkwy., Herndon, from Lerner Enterprises. Julien J. Studley Inc. was the leasing agent.

Sverdrup Corp., an engineering firm, leased 17,000 square feet at 7799 Leesburg Pike, Tysons Corner, from Lerner Enterprises and the Lenkin Co. Barrueta & Associates was the leasing agent.