Construction of single-family houses moved upward a little bit in April, the Commerce Department recently reported.

Overall starts dropped 12.8 percent to a seasonally adjusted 458,000 units, although that was confined to multifamily housing. Single-family housing grew 2.8 percent to 368,000 units.

"With some of the best home-buying conditions of a lifetime now in place -- including historically low mortgage rates, affordable prices and a first-time home buyer tax credit -- single-family builders are starting to see the light on the horizon as more consumers realize they can now obtain the home of their dreams," said NAHB Chairman Joe Robson. "Meanwhile, the extreme difficulty that builders are encountering in obtaining financing for new multifamily structures has ground production in that sector almost to a halt."

The ongoing credit crisis is preventing the multifamily housing sector from improving, said NAHB chief economist David Crowe.

"A severe credit crunch for acquisition, development and construction financing and a lack of investor interest in low-income housing tax credits are the main factors that are keeping apartment builders from moving ahead with new projects, along with the competition from excess inventory that's on the market," Crowe said. "Ultimately, the logjam in builder financing must be broken in order for housing construction to provide the boost that the national economy needs to get back on track."