Rates on 30-year mortgages rose last week for the first time in five weeks, according to a nationwide survey.

Freddie Mac said Thursday its weekly survey showed that rates on 30-year fixed-rate mortgages averaged 5.63 percent, up from 5.56 percent last week. It was the first increase in five weeks and only the second gain in the past 11 weeks.

The recent decline in mortgage rates helped push sales of both new and existing homes to record levels in April and provided support for a boom in housing construction.

The government reported Thursday that builders began construction at an annual rate of 2.009 million homes and apartments in May, up 0.2 percent from the April pace.

Despite the fact that the Federal Reserve has been raising short-term interest rates for a year, long-term rates, including mortgage rates, have been falling for much of this year, providing support for the red-hot housing market.

Frank Nothaft, chief economist at Freddie Mac, noted that the low mortgage rates pushed applications for mortgages to purchase homes last week up to the highest level on record, according to a Mortgage Bankers Association survey.

"Although the 30-year mortgage rate ticked up this week, which wasn't completely unexpected, it is still below last year's annual average and well below where it was at this time last year," Nothaft said.

For 15-year fixed-rate mortgages, a popular option for refinancing, rates rose to 5.22 percent, up from 5.14 percent last week.

Rates on one-year adjustable-rate mortgages averaged 4.25 percent, up from 4.21 percent last week.

For five-year hybrid adjustable-rate mortgages, rates were at 5.10 percent, up from 5.01 percent last week.

The nationwide averages for mortgage rates do not include add-on fees known as points. The one-year ARM had an average fee of 0.7 point and the other three mortgage categories carried fees of 0.5 point.

A year ago, 30-year mortgages averaged 6.32 percent, 15-year mortgages were at 5.70 percent and one-year ARMs averaged 4.13 percent. Freddie Mac does not have historical data on the five-year ARM, which it began tracking this year.

PERSONNEL . . . IDI Group of Arlington named Norman M. Dreyfuss chief operating officer. Dreyfuss, who has been with the development company since 1981, most recently was an executive vice president, directing development of its Leisure World communities in Maryland and Virginia. . . . Bozzuto Homes Inc. of Greenbelt named Caren Garfield and Ross Little development managers.

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