SAN FRANCISCO (KGO) — Building new housing is a priority across the state, especially in fire ravaged areas of Southern California.

But now a growing number of environmental groups say they want to make sure that future construction isn’t putting communities at risk from climate change.

They’re pointing to a provision in a recently passed budget bill, AB 306, which could essentially freeze new residential building regulations for the next six years and bars cities and counties from adopting stricter codes.

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David Lewis is executive director of the nonprofit Save the Bay. His group is concerned that the bill will slow climate resiliency efforts, including upgrades meant to protect communities from flooding and other effects of sea level rise.

“Cities need to be able to adapt to climate change, wildfire, increased flood risk and other hazards. And cities in the Bay Area want to adapt to climate change. This bill makes it very difficult for them to make buildings and neighborhoods safe,” says Lewis.

Authors cite the state’s critical shortage of housing and the urgency to rebuild from the Sothern California fires, and they expect the freeze on state building standards to encourage new construction. Even if the law is well intended, others warn of unexpected consequences.

Len Materman directs the San Mateo County-based planning group OneShoreline, which has helped develop climate resilient strategies for projects including housing.

“The unintended consequences can be that housing is built in a way that doesn’t comply with cities’ or counties’ desires about how and where to grow. And so there’s concerns about whether housing will come in that isn’t resilient to climate change,” says Lewsi.

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He believes the cost of retrofitting down the road could be far more expensive. The new law does contain exceptions in cases of health and safety and fire hardening upgrades, but critics call the language vague.

At least two dozen environmental groups have come out in opposition, worrying the freeze could cripple residential carbon programs, including efforts to limit the installation of gas appliances. They’ve written to Bay Area lawmakers, demanding changes before the law takes effect.

“Whatever the intent this building has, whatever the legislature was thinking, this bill has unintended consequences. It’s going to prevent cities in the Bay Area from protecting their citizens and communities against increasing flood risk,” Lewis argues.

The concerns over the build code freeze follows Governor Newsom’s recent rollback of protections contained on the California Environmental Quality Act known as CEQA, also promoted as a way to streamline housing construction in the state.