Western Development Corp., one of three owners of the Georgetown Park shopping mall, and Kan Am Realty of Atlanta, Ga., have entered into a joint venture to develop the Briggs-Chaney Shopping Center in Montgomery County.

The 194,000-square-foot complex, which is under construction on a 19-acre site at Route 29 and Briggs-Chaney Road, will include a Safeway supermarket and a First Maryland Savings and Loan branch office.

Construction financing for the $15 million center is being provided by Chase Manhattan Bank.

Western Development Corp. and Kan Am Realty are also partners in the Greenway Shopping Center in Greenbelt and in Germantown Commons in Germantown.

The Briggs-Chaney project is scheduled to open in the summer of 1983.

Developments in real estate in the Washington area:

* Construction has been completed on the condominium office project at Foxhall Road and MacArthur Boulevard NW. The building contains 15 build-to-suit suites ranging from 1,000 to 13,600 square feet. An underground garage accommodates 70 cars. The cost of the project was about $6 million.

* Barkley Pierce O'Malley Architects and Planners has been awarded a contract to design the Falls Church headquarters of the National Association of Plumbing-Heating-Cooling Contractors. The structure will be located on a 40,350-square-foot site at the intersection of Washington Street and West Annandale Road. Construction is scheduled to begin this summer, with occupancy in 1983.

* Litton Computer Services, a division of Litton Industries, has begun construction which will add 22,000 square feet of space to the company's existing building in Reston. The addition will more than double the size of Litton's headquarters there.

* Automated Sciences Group Inc., a minority-owned engineering and computer services company, has leased 2,310 square feet of space at 1725 Jefferson Davis Highway in Arlington.

* William H. Gordon Associates, a civil engineering consulting firm, has leased 3,711 square feet of space at Commerce Park Two in Reston.

* Administration Associates Inc., a firm which administers insurance programs for associations, has leased 2,023 square feet at 734 15th St. NW. The company has its main office at 1729 H St. NW.

* Computer Consoles Inc. has leased 10,165 square feet of space at 962 Wayne Ave., Silver Spring. The company provides turn-key systems to the Bell System and is currently involved in entering the office automation business.

* Bethany Travel Inc. will relocate later this month to a 2,084-square-foot office at 1600 Wilson Blvd. in Arlington.

* Sisk Mailing Service Inc. of Lanham has sublet a 40,000-square-foot warehouse at 3370-90 V St. NE.

* Vinzant and Associates, a Washington-based engineering firm, recently purchased a building at 1115 Main St. in Lynchburg to house its staff there.

* Air Techniques Inc., a manufacturer of high-efficiency air filters for pharmaceutical, electrical and nuclear industries, has purchased a 25,000-square-foot building on a one-acre lot at 1801 Whitehead Road in western Baltimore County's Security Industrial Park. The seller was Parkton Co., a clothing distribution firm. The sale price for the property was $575,000.