SEATTLE-Higher mortgage rates are slowing the pace of home sales in a variety of ways, two online brokerage firms say. Locally based Redfin says a survey of prospective buyers found that a majority blame rising rates for making homes less affordable as well as for influencing them to change the pace of their search, while ZipRealty reported that the average length of time a home is on the market ticked upward in its most recent report.

“Higher mortgage interest rates and the seasonal slowdown that typically occurs in the fall are expected to cause a degree of moderation in housing market trends,” says Lanny Baker, president and CEO of Emeryville, CA-based ZipRealty. “For the first time in several months, the median days on market ticked upward in the current report to 28 days from 27 days a few weeks ago. More than half of the cities studied saw the length of time it takes to sell a house rise by a day or two.”

However, Baker adds that sellers continue to bring an increasing amount of for-sale inventory onto the market. There were 173,000 new listings in the recent 30-day period, a 10% increase over the prior year. “And those new listings are selling well, with an average sold-to-list price ratio of 99.1%,” he says.

Redfin's survey, based on feedback from 1,722 would-be buyers who had toured a home with a Redfin agent in one of 22 metro areas across the US, found 63% of respondents indicating that rising mortgage interest rates are making it harder for them to afford a home. A majority of respondents said rising mortgage rates caused them to alter the pace of their home search, with 33% speeding up their search in an effort to beat further increases, 28% slowing down the search and 1% calling it off.

Even so, 63% of buyers believe that now is a good time to sell a home in their neighborhood. That's down from 66% last quarter, the first drop in three quarters. Twenty-four percent said that now is a good time to buy a home in their neighborhood, and that figure too is down from 32% last quarter and from the peak of 48% in the fourth quarter of last year.

Fifty-eight percent of buyers cited low inventory as a major concern with buying a home now. That's down from 66% last quarter and five points more than the 53% of respondents who ranked rising mortgage rates at the top of the list.

"Our survey results underscore buyer sensitivity to this summer's mortgage rate fluctuations," says Redfin economist Ellen Haberle. "Should interest rates spike again in the coming months in response to a tapering by the Federal Reserve of asset purchases, we could see a significant drawback or even a temporary freeze in buyer activity."

However, the residential market shows continued strength. ZipRealty reports that median home sales prices were up 16.2% year-to-year to an average of $278,000 in mid-August across 24 markets analyzed by ZipRealty. The firm also reported that new pending sales were up 19% in mid-August compared to a year ago.