The time appears right to lease office space in suburban Washington, with the vacancy rate at its highest mark in five years, according to the Spaulding & Slye Suburban Washington Report for the first quarter of 1986.

Vacant office space nearly doubled this year, and heavy construction activity continues to add to the oversupply of space, making leasing favorable, according to Thomas G. Owens, vice president and brokerage manager of Spaulding & Slye.

The amount of available space increased to 10.2 million square feet this year, up from 5.6 million square feet in the first quarter of 1985. A 10 percent increase in total space in the past three months contributed to the oversupply, according to the report.

"We have seen an increase in the vacancy rate over the last couple of years, but the space being absorbed has also been phenomenal. The amount of space delivered is high, but the absorption rate is also at record levels," said Vincent Chiarello, vice president and regional manager of Virginia leasing for Smithy Braedon Co.

The amount of space leased hit a record 3.4 million square feet in the first quarter of 1986, bringing the total space absorbed to 9.5 million square feet in the past 12 months.

"For tenants moving into the area without prejudice of location, the Reston/Dulles corridor is a good place to look," said Owen. "That area has experienced the largest growth rate in the past two years and has many good benefits for the amount of money being spent."

Among area jurisdictions in the first quarter of 1986:

Alexandria delivered 250,000 square feet and absorbed 164,000 square feet. The vacancy rate remains unchanged at 20 percent, but is up from 11 percent in the first quarter of 1985. Favorable leasing is projected when the 529,000 square feet under construction are delivered.

Fairfax County, which accounts for 40 percent of the space in the area, delivered 2.5 million square feet of space, increasing its market size to 26.63 million square feet. The vacancy rate is up 3 percentage points to 17 percent, while in the Reston/Herndon and Tysons Corner areas, the rate increased by 1 percentage point. Vacancy is expected to rise when the 6.7 million square feet under construction are delivered.

Montgomery County's vacancy rate rose by 3 percentage points to 17 percent. The county delivered 1.9 million square feet and absorbed 1 million square feet. Silver Spring appears to have the healthiest market, with vacancy decreasing to 7.3 percent. An 82 percent increase in total space is expected next year.

Bethesda delivered 800,000 square feet, causing vacancy to jump 5.5 percentage points to 13.5 percent. Vacancy is expected to continue rising when 35 percent of the 2 million square feet proposed for Montgomery County are delivered in Bethesda.

Prince George's County delivered 100,000 square feet, but absorption dropped to zero. The vacancy rate stayed at 17 percent. An additional 850,000 square feet are under construction and another 330,000 square feet are proposed, which could cause the vacancy rate to escalate.

Arlington delivered 180,000 square feet and absorbed 107,000 square feet. The vacancy rate was the lowest in the area at 4 percent, but is expected to increase when the 1 million square feet under construction in Ballston are delivered.

Friedman, Fuller & Hudson Inc. of Rockville acquired the following three firms to expand its risk management services: P. H. I. Risk Science Inc., P. M. Hudson Associates and Parks-Hudson Inc. Friedman, Fuller acquired assets of all three companies.

American Management Systems Inc., which declared a 2-for-1 stock split, said it intends to repurchase up to 100,000 shares of its common stock after the split to offset dilution of the Employe Stock Ownership Plan.

After the split, the company will have 4,927,192 shares outstanding.

Baily, Deardourff, Sipple and Associates, of McLean, and Earle Palmer Brown Associates, of Bethesda, teamed up to form Strategic Media Group, a company that will buy media time for clients.

BDS&A, a political advertising and consulting firm, approached EPBA with the venture hoping to establish a local company that could buy time for election and issue-oriented campaigns. Diane Eizen, a political time-buying specialist from Philadelphia, will head the four-person operation at EPBA's Bethesda office.

Capitol Tech received a grant from Digital Equipment Corp. of Massachusetts that will enable the presidents of 16 Maryland colleges and universities to communicate via computer next year.

The Laurel engineering technology college will install a digital VAX-11/750 that allows electronic linkage between members of the Maryland Independent College and University Association.

James River Corp. of Richmond announced plans to purchase all outstanding shares of Canada Cup Inc., the leading manufacturer of plastic and paper food products in Canada.

The transaction was approved by Investment Canada, and closing is expected in mid-May. The purchase price was not disclosed.

Canada Cup has six manufacturing facilities in Canada and the United States and employs 535 people. All of its products are marketed under Canada Cup and Dixie trademarks. Sales in 1985 were $60 million in Canadian dollars.