Gavin Newsom signs two laws to ease California’s housing crisis.

With the recall behind him, Gov. Gavin Newsom of California has begun working through the hundreds of bills that piled up on his desk during the campaign. On Thursday, he turned to housing, signing a pair of measures to speed construction in the state.

The first, called Senate Bill 9, would essentially eliminate single-family zoning by allowing duplexes in most neighborhoods across the state. The other, Senate Bill 10, would reduce environmental rules on multifamily housing and make it easier for cities to add high-density development.

Faced with a deepening housing affordability crisis, Mr. Newsom has poured billions of dollars from the state’s budget surplus and federal stimulus packages into investments to ease problems with housing and homelessness. But California remains one of the hardest places in the country to build, resulting in a longstanding housing shortage that is the root of its cost problems.

For years, the state legislature has tried to pass state pre-emption rules that force local governments to allow higher-density housing in single-family housing neighborhoods. But resistance from suburban cities and homeowners has been fierce.

The passage of S.B. 9 and S.B. 10, which passed the Legislature in August after earning bipartisan support in a state dominated by Democrats, represents the capstone of those efforts. It is part of a nationwide trend in which other states faced with similar growing housing affordability problems have assumed more power over housing, which has traditionally been the province of local government.

“The housing affordability crisis is undermining the California Dream for families across the state, and threatens our long-term growth and prosperity,” Mr. Newsom said in a news release.