Fixed mortgage rates dipped to a record low for the second consecutive week as borrowing costs remain low to support the housing recovery.

The 30-year fixed-rate mortgage fell to 3.31 percent for the week ending Nov. 21, from last week's 3.34 percent and a year ago when it was 3.98 percent, according to Freddie Mac.

The 15-year fixed-rate mortgage dropped to 2.63 percent from 2.65 percent lats week and 3.3 percent a year ago at this time.

Freddie Mac supports one in four home buyers with financing.

"Fixed mortgage rates continued to ease somewhat this week to record lows and should help the ongoing housing recovery," said Frank Nothaft, Freddie Mac's vice president and chief economist.

On Tuesday, the Commerce Department reported that construction on new homes rose 3.6 percent in October to an annual pace of 894,000, the best rate since July 2008.

Existing home sales increased 2.1 percent in October to an annualized pace of 4.79 million, higher than expected.