Rates on 30-year mortgages rose for the first time in five weeks as investors awaited word from next week's meeting of the Federal Reserve on the future direction of mortgage rates.

In its weekly survey Thursday, Freddie Mac reported that the nationwide average for rates on 30-year, fixed-rate mortgages rose slightly this week to 5.74 percent, from 5.71 percent last week. It was the first increase for the 30-year rate since Aug. 11, when it rose to 5.89 percent.

Analysts attributed the slight increase to investor concern about what the Federal Reserve might do next week.

Many private economists believe the Fed will nudge a key short-term rate it controls up by another quarter-point at the Tuesday meeting, which would be the 11th rate increase since the Fed began gradually raising rates in June 2004. Some analysts argue, however, that the Fed may decide to pause in its rate increases next week until it can further judge the adverse impacts of Hurricane Katrina on the economy.

Rates on 15-year, fixed-rate mortgages, often used for refinancing a home mortgage, averaged 5.32 percent this week, up from 5.30 percent last week.

One-year adjustable rate mortgages rose slightly to 4.46 percent from 4.45 percent last week. In mid August, one-year ARMs hit their highest level in more than three years at 4.58 percent.

Rates on five-year hybrid adjustable rate mortgages averaged 5.26 percent this week, up from 5.24 percent last week.

The nationwide averages for mortgage rates do not include add-on fees known as points. All loan categories carried a nationwide average fee this week of 0.6 point.

A year ago, 30-year mortgages averaged 5.75 percent, 15-year mortgages were at 5.13 percent and one-year ARMs averaged 4.03 percent. Freddie Mac does not have historical data on the five-year ARM which it began tracking this year.

COMPANIES . . . Washington Fine Properties LLC, a real estate brokerage with offices in the District and Potomac, plans to merge with Armfield, Miller & Ripley Inc., a brokerage with offices in Middleburg and Washington, Va. The Virginia offices are to operate as Armfield, Miller & Ripley Fine Properties LLC. The D.C. firm has about 70 agents; the Virginia firm has about 50. The privately held companies did not disclose financial details.

EVENTS . . . "Building for the 21st Century: The Solar Patriot Home" is the topic of a program at 12:30 p.m. Tuesday at the National Building Museum, 401 F St. NW, Washington. Alden Hathaway, director of the Clean Power Program at the Environmental Resources Trust, is to discuss how his solar, zero-energy home has fared since the demonstration building, visited by 20,000 people on the National Mall in 2001, was moved to Loudon County. Professionals may earn one continuing-education credit. Admission is free. For information, call 202-272-2448; Web site: nbm.org.

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