Work has been started on a $10 million complex of five low-rise office buildings on a 16-acre Alexandria site where the commercial zoning would have permitted a height of 150 feet and far heavier density.

The Mark Center office space, is a project of the Winkler Co's., which earlier developed four communities of Hamlet garden apartments on land around Beauregard Street and just south of Seminary Road. There are 2,281 rental apartments on the Hamlets and 2,340 rental apartments in the high-rise Southern Towers buildings on the north side of Seminary Road, which intersects Shirley Highway.

Development of the Mark Center office park on part of 150 undeveloped acres still held by the Winkler group marks another stage in the building projects that began in 1938 when the late Mark Winkler acquired a total of 423 acres. The Fairfax County tract was rezoned C-2 in 1952 and later annexed by Alexandria. Portions later were sold for the nearby Southern Towers and Seminary Towers high-rise apartments.

Charles E. Hudson, director of development for Winkler, said that initial occupancy in the new office park is expected next summer at rates of $9 to 10 a square foot. That figure is $2 less than the amount for prime-location new downtown office buildings.

Site and facade designs for the earthtone-brick Mark Center office buildings were done by Sasaki Associates of Watertown, Mass. The Nothern Virginia firm of Dewberry, Nealon and Davis is doing working drawings, plus civil and structural engineering.

The builder is Eugene Simpson & Brother, Inc. and Strickler Associates is handling mechanical engineering.

Robert T. Gates, president of Winkler, said an architectural and planning competition was held for Mark Center, with all the competing firms being paid a fee. He added that isntructions included a stipulation that density should be only 15 per cent of the maximum permitted and that 60 per cent of the site was to be green space.

Plans also call for three restaurants to be located in the new office buildings and for 639 "well-screened surface parking spaces nearby."

Winkler's Virginia management companies, now located nearby, will be moved to the new Mark Center.

Gates said that planning efforts are still under way for the remaining 130 undeveloped acres between Beauregard Street and Shirley Highway.