U.S. housing starts and building permits fell more than expected in May, suggesting the housing recovery will likely remain slow for a while. Groundbreaking for homes fell 6.5 percent to a seasonally adjusted annual pace of 1 million units, the Commerce Department said on Tuesday. Groundbreaking for single-family homes, the largest part of the market, fell 5.9 percent in May to a 625,000-unit pace, while starts for the volatile multi-family homes segment decreased 7.6 percent to a 376,000-unit rate.