Applications for U.S. home mortgages rose last week as loan requests for new purchases hit its third straight high point on the year and fixed 30-year mortgage rates hit a historical low, an industry group said on Wednesday.

The Mortgage Bankers Association said its seasonally adjusted index of mortgage application activity, which includes both refinancing and home purchase demand, rose 6.2 percent in the week ended Dec. 7.

The MBA's seasonally adjusted index of refinancing applications rose 8.0 percent, while the gauge of loan requests for home purchases, a leading indicator of home sales, rose 0.7 percent, hitting another high point on the year and growing for a fifth straight week.

The refinance share of total mortgage activity rose to 84 percent of applications from 82 percent the week before.

Fixed 30-year mortgage rates averaged 3.47 percent in the week, down 5 basis points from 3.52 the week before. This is the lowest in the history of the survey.

The Federal Reserve has been buying $40 billion worth of mortgage-backed securities each month since September, and it is expected to announce new Treasury bond purchases on Wednesday.

The survey covers over 75 percent of U.S. retail residential mortgage applications, according to MBA.