Hecht's, the local department-store chain, is gearing up for expansion in the 1990s with additional retail and distribution space, according to Lacy Womack, senior vice president for operations.

Currently under way is a $5 million project to expand the New York Avenue distribution center by building a 40,800-square-foot addition behind the existing 643,000-square-foot facility. Hecht's is destroying three buildings to construct the new facility.

"The construction will join the shipping and receiving areas of the complex in a cross-dock arrangement," Womack said. "The purpose is to improve the efficiency of our distribution operation and to prepare to accommodate the addition of several new stores in the short-term and long-range future of Hecht's."

The New York Avenue complex is the distribution center of all "soft" goods, including apparel, cosmetics and jewlery, for Hecht's in the Baltimore-Washington area. The center services 23 stores, but will be redesigned to handle up to 10 more.

Plans have been announced to open stores in Owings Mill and Glen Burnie by February 1987.

Completion of the addition, which will be built by Giant Construction Inc., is scheduled for July 1987.

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

*The Ramada Inn/Seminary Plaza in Alexandria reopened Friday after finishing a $3 million project to renovate all guest rooms and public areas in the hotel. The project included renovating an existing restaurant and adding a night club.

*Alan M. Porter & Associates, a Silver Spring public-relations firm, has moved its corporate headquarters to an expanded, 380,000-square-foot facility at 8700 Georgia Ave. in Silver Spring.

*William H. Gordon Associates Inc., a civil engineering firm in Northern Virginia, opened its new corporate headquarters in The Overlook Building in Reston.

*Bengtson, DeBell, Elkin & Titus, P.C., a Virginia engineering and landscaping firm, began construction on a new office at 4379 Davis Ford Rd. in Woodbridge.

*According to The Kenneth H. Michael Cos. Inc., Dr. George Malouf of Hyattsville, a board member of Prince George's Hospital, bought The Kenilcrest Building in Cheverly. The transaction was worth more than $1.8 million

*Saco Inc., an Ohio corporation that remanufactures automotive parts, will build a 30,000-square-foot facility on five acres in Charles City County's Roxbury Industrial Center. The site will be the company's headquarters, sales office and training center.