The $22 million Presidential Plaza, on the corner of 19th and I streets, has been completed and is ready for occupancy.

The eight-story building and clock tower was built by Omni Constuction Inc. and will offer the I Street corridor approximately 100,000 square feet of additional office and retail space.

A spokesman for the developer of the facility, Oliver T. Carr & Co., said that more than half of the available office space has been rented.

Seven tenants, including the U.S. Telephone Association and the Aluminum Association, have leased 52 percent of the available 92,000 square feet of office space. The 8,000 square feet of retail space is vacant and being leased by the developer. The building also has a two-level underground parking garage.

The building, designed by Keyes Condon Florance Architects, is a polished granite with tinted windows and a clock tower that rises two stories above the eighth floor, overlooking the intersection of 19th and I streets.

Other recent developments in commercial realty in the Washington metropolitan area:

*The George Hyman Construction Co. completed construction on the $125 million Capitol Place. The development includes a 272-room Sheraton Grand Hotel and three 12-story office buildings containing 620,000 square feet of leasable space.

*Cambridge Development Co. has begun construction on the $23 million Monroe Business Park in Herndon. The seven-building park will have a total floor space of 264,575 square feet upon completion this summer.

*The American Bankers Association has renewed and expanded its lease at the Bender Building on 1120 Connecticut Ave. NW. The 134,261-square-foot lease has an aggregate value in excess of $40 million.

*Motorola Inc. has leased 43,785 square feet at Tysons Commerce Center in Tysons Corner. The five-year lease has an aggregate value of $4.7 million.

*Mutual of Omaha has leased 31,083 square feet in the DANAC Office Park on Gaither Road in Rockville. The lease has an aggregate value of $2.1 million.

*American Medical International/The George Washington University Health Plan has leased 14,463 square feet in the Beauregard Square Office Complex in Alexandria and 14,470 square feet at 7474 Greenway Center Dr. in Greenbelt. The two five-year leases have a total value of $2.1 million.

*The African Development Foundation leased 14,575 square feet in the Air Line Pilots Association building on 1625 Massachusetts Ave. The five-year lease has a value of $1.6 million.

*Montgomery Community Television leased 10,000 square feet in Metro Park North for its permanent headquarters and studio. Metro Park North is located at 7548 Standish Place in Rockville.