According to a recent survey by Julien J. Studley Inc., 266,376 square feet of building space was leased in Washington during July and August, bringing the total for the year to just under 2.35 million square feet. Most of the space leased during this period was in small units.

"It appears that this year will still be a record one, with absorption reaching as high as 3 million square feet for the year," said Studley Washington corporate vice president Stephen Goldstein. "We are well ahead of last year's total leasing and are close to 70 percent ahead of last year's leasing for the first eight months in new office buildings."

Since January, more than 2.01 million square feet have been leased in new office buildings, compared with 1.21 million square feet during the same period of 1980. Average rental costs for new space in the District have increased by $5.20 since the first of the year, to $27.53 a square foot, and by $1.94 for old space, to $23.03.

During the July/August period in northern Virginia, 365,578 square feet were leased in new buildings. In Maryland, new building leases totaled 245,786 square feet.

* Ground-breaking took place for a $3 million auditorium and classroom building at Johns Hopkins University Applied Physics Laboratory in Howard County, Md. The building, scheduled for completion in late 1982, will cover 44,000 square feet, including a 500-seat auditorium and eight classrooms. Construction will be done by Henry H. Lewis Inc. of Owings Mills, Md.

* The American Alliance, a nonprofit educational association representing health, physical education, sports and recreation professionals, dedicated their national headquarters in Reston last week. The 30,000 square foot, $1.5 million building, designed by William R. Vosbeck of VVKR Partnership in Alexandria and built by Silver Spring's Baron Builders, has been occupied for about a year.

* Macklin-Hansen Real Estate Corp. has been named as exclusive agent for the 1406 King St. Limited Partnership. The group is building a 30,000-square-foot, $3.3-million office building in Old Town Alexandria