The number of permits issued for new single-family home construction in the Washington area dipped during the first six months of the year compared with the same period last year, according to U.S. Census Bureau figures.

Overall, 13,052 permits were issued, a 13 percent decline from the 14,945 granted during the first half of 1986.

Several jurisdictions showed significant declines. Loudoun County issued 45 percent fewer single-family home building permits. During the first six months of this year, Loudoun granted 547 permits compared with 991 in the same period last year. Charles County's total also dropped sharply, with 516 permits issued, 36 percent below the 808 issued during the first half of 1986.

The biggest decrease numerically occurred in Fairfax County, which had an 18 percent drop. The county issued 3,982 permits during the first half of the year, the most in the Washington area but down from 4,865 approved during the same six-month period in 1986.

Montgomery, Prince George's and Prince William counties had the smallest drops. Montgomery approved 3,814 this year, a 1.2 percent decline from the 3,861 it issued during the same January-to-June period in 1986. Prince George's granted 2,357, down almost 4 percent from the previous year's six-month figure of 2,453. Prince William issued 1,580, a 4.6 percent decrease from the 1,656 it approved in the first half of 1986.

Only one jurisdiction, the District of Columbia, showed an increase, a numerically insignificant jump from 70 permits issued in the first half of 1986 to 112 this year.

Michael Carliner, an economist for the National Association of Home Builders, attributed the decline to the scarcity of available land on which to build, which has driven up land prices considerably. He said that builders consequently have found they can make more money from land they own by building multifamily housing than by putting up single-family homes. The single-family houses they are building are becoming much more expensive, Carliner said.

During the first half of this year, the number of building permits for new apartments rose 47 percent compared with the number issued during the same period in 1986.

"When you have high land costs, you either have to build higher-density projects or more expensive houses," he said.

Monte West, president of West Homes Inc., which builds single-family houses, also attributed the decline to higher interest rates this past spring, which discouraged some people from buying.

But he blamed the decrease in Fairfax County on the long delays builders are experiencing in getting the county's Division of Design Review to approve subdivision plans. Because of the delay in getting plans approved, which West said took as long as six months, builders "had no lots to build on," even though state law requires the county to process preliminary site plans within 60 days. "You can't take out {building} permits until subdivisions are approved," West said.

Claude Cooper, director of Fairfax County's Environmental Management Department, which oversees the design review division, said the decline should not be attributed to delays in his office, but to a lack of construction workers and "other market forces.

"We don't feel a decrease could have resulted from a slowdown in the Fairfax County review process," Cooper said.

He rejected the contention of some builders that the county is trying to control growth by delaying approvals. He said the number of unapproved site plans that have exceeded the state-mandated 60-day approval period has dropped from 138 on April 8 to 24 on July 10.

Russ Morgan, chief of Charles County's building permit and inspection division, offered another explanation for the decline in his jurisdiction.

"In 1986, we lumped town houses and single-family home {permits} together. But what may have confused the Census Bureau is that this year we broke out single-family homes" from the reports. He said that the number of new single-family home construction permits in Charles County is actually 100 ahead this year over the same period in 1986. Said Morgan: "Maybe when the secretary got the call from the Census Bureau, she got the figures wrong and read off the numbers for single-family houses only."

IN THE BUSINESS ... Lerner Enterprises and Senate Construction have started construction at One Sterling Park Business Center, the initial phase of the Sterling Park Business Center, a 75-acre, 1-million-square-foot industrial park off Rte. 28 in Loudoun County ... Weaver Bros. Inc. says it closed more than $225 million in loans in fiscal 1986, a record for the company ... The Northern Virginia Housing Resource Board and the Northern Virginia Board of Realtors are taking scholarship applications from minority persons who wish to enter the real estate profession in Northern Virginia. The aid would pay for books and tuition for licensure preparation courses and the fee for the required examination by the Virginia Board of Realtors. The scholarship assistance was made available through a Department of Housing and Urban Development grant ... Centennial Cos. have been formed, which include the existing Centennial Development Corp. and Centennial Contractors and two new operating companies, Centennial Management Corp. (the firms' leasing arm) and Centennial Investment Corp. (which will seek real estate opportunities for the firms).

PERSONNEL FILE ... Capital Homes Inc. has appointed Franc Myers vice president and division manager ... Thomas F. Baker has been named vice president of sales and marketing for Fairfield Homes in Woodbridge ... John W. Bartling Jr. has been named vice president for project finance at the National Corporation for Housing Partnerships.