Sekisui House Ltd., the nation's second-largest home builder, will focus on the domestic market after expanding overseas as it expects Japan's biggest housing boom in at least 15 years after the March 11 disaster.

Housing starts, which dipped below 1 million in 2009 and 2010 for the first time in four decades, may rebound as homeowners rebuild in the quake area, Isami Wada, chairman of the Osaka-based company, said in an interview.

"We had to expand overseas because signs of a slowdown in Japan's housing demand were alarming," Wada said in Tokyo. "Unexpectedly, the earthquake struck. I now anticipate annual housing demand to reach the 1 million unit level again due to revival efforts and reconstruction demand."