A 12-story office building with a natural stone facade will be started soon on the site of the former YWCA building that has been razed at the northwest corner of 17th and L streets NW. Completion is scheduled for June 1983.

The 180,000 square foot building will be owned by 1667 K Street NW Associates, a limited partnership involving the John Akridge Co. and Penn Mutual Life Insurance Co. The Akridge firm is the developer. Salus Corp. is the general contractor, and the architect is Weihe, Black, Jeffries, Strassman & Dove.

The building will have retail space on the first and basement levels and parking on three levels. Rental rates for office and retail space are expected to range from $35 to $42.50 a square foot.

In the Landover area of Prince George's County, ground has been broken for the second phase of Landmark Associates' Metroplex II building designed by Arthur Cotton Moore. The site is near the Metro station. Completion of the second building, which will be joined to a lower-rise existing building, is scheduled next spring. The Braedon Companies handles the management and leasing.

The National Cable Television Association has leased the new building at 1724 Massachusetts Ave. NW for its headquarters. Sub-tenants in the seven-story, glass-and-brick building will be A.T. International, a consulting firm, and the law firm of Bingham, Dana and Gould. The building, not surprisingly, will be wired for cable television and will have a microwave link for television signal reception from Communications Technology Management's earth stations at Bren Mar, Va.

Greenhoot Inc. announced that the International Bank for Reconstruction and Development will take most of the space in the new 90,000 square foot building at 2131 K St. NW. Occupancy is scheduled in July.