Mortgage rates fell this week, with rates on 30-year mortgages dropping to their lowest level in five months.

Freddie Mac, in its weekly nationwide survey released Thursday, said rates on 30-year fixed-rate mortgages averaged 5.77 percent, down from 5.82 percent last week. It was the lowest since rates averaged 5.52 percent for the week ended April 1.

Rates on 30-year mortgages hit a high this year of 6.34 percent the week of May 13. Since then, rates, while bouncing around, have slowly drifted downward as economic activity cooled in the late spring and early summer.

Frank Nothaft, Freddie Mac's chief economist, said a decline in consumer confidence reported this week has raised concerns among some Wall Street investors about consumers' willingness to spend in the coming months. "The drop in consumer confidence left an unsavory taste in the market, creating a fear that consumer spending will slow," he said. "Because consumer spending constitutes about two-thirds of the economy, this could seriously impact economic growth. As a result, interest rates tend to retreat to lower levels."

For 15-year fixed-rate mortgages, a popular option for refinancing, rates dipped this week to 5.15 percent, from 5.21 percent last week. Rates on one-year adjustable rate mortgages declined to 3.97 percent, from 4.05 percent last week.

The nationwide averages for mortgage rates do not include add-on fees known as points. The 30-year mortgage and the one-year ARM each carried an average 0.8 point fee this week. Fifteen-year mortgages carried a 0.7 point fee.

EVENTS . . . The National Building Museum, at 401 F St. NW, Washington, plans the family program "Crazy Construction for Kids" tomorrow at the museum. The program is presented in conjunction with the exhibition "Symphony in Steel: Ironworkers and the Walt Disney Concert Hall," which features architect Frank Gehry's use of stainless steel and titanium. Participants can build their own model designs with shiny materials. Fee: $4 per building. For information, call 202-272-2448; Web site: www.nbm.org . . . . . . The rebuilding of Lower Manhattan after the 2001 attacks on the World Trade Center is to be discussed by New Yorker magazine architecture critic Paul Goldberger at a lecture Tuesday from 6:30 to 8 p.m. at the National Building Museum, 401 F St. NW, Washington. Afterward, he signs his new book, "Up from Zero: Politics, Architecture, and the Rebuilding of New York" (Random House, $24.95). Admission is $17, students $5; registration is required. Call 202-272-2448; Web site: www.nbm.org.

PERSONNEL . . . Mark A. Babbitt was named vice president of Slenker Land Corp., a Burke community developer. Babbitt previously served as development manager for Higgins Development Partners, a subsidiary of Pritzker Residential.

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