Residential building activity grew 2% in February even as the construction industry experienced a 9% drop in project starts for the first two months of 2011, McGraw-Hill Construction said Wednesday. The research firm, which studies residential and nonresidential construction trends, said a spike in multifamily housing projects spurred growth in residential construction last month, offsetting a decline in single-family homebuilding. Troubles in the single-family segment were further highlighted in a Commerce Department report, which showed housing starts fell 22.5% in February to the lowest rate in almost two years. The total value of new residential construction projects climbed 2% to $121.1 billion in February, up 2%, thanks to a 67% surge on the multifamily side of the market, McGraw-Hill Construction said. The multifamily segment was lifted by several major deals worth more than $55 million a piece, including a New Jersey apartment complex valued at $140 million. “Multifamily housing is turning out to be one of the few near-term bright spots for the construction industry,” said Robert Murray, vice president of economic affairs for McGraw-Hill Construction. “While rising from a very low amount, multifamily housing in 2010 grew 12% in dollar terms, faster than the 6% gain reported for single family housing, and it’s expected to see another double-digit increase in 2011.” As the multifamily segment experienced a resurgence of activity in February, single-family construction fell 7%, with every major geographic region experiencing a slowdown in building within this segment, McGraw Hill said. Write to Kerri Panchuk.