The ordinance, which goes into effect May 9, ties development to the size and steepness of lots, as well as zone. Residents have complained for years about “mansionization,” a phenomenon where remodeled or new homes dwarf nearby dwellings, compromising privacy, vistas, and the character of neighborhoods.

“There is nothing, I think, more upsetting to those of us who live on hillsides than to see this beautiful landscape completely destroyed by a big box. “ Villaraigosa told reporters gathered in the mayor’s press room at City Hall.  

The new hillside restrictions cover roughly 133,600 single-family homes, according to the Department of City Planning, spanning such neighborhoods as Laurel Canyon, Bel Air and Mount Washington.

While the news conference was packed with supporters, some in real estate fear the new rules will prohibit creativity in design. James W. Litz of the Beverly Hills Greater Los Angeles Association of Realtors acknowledged abuses exist--including developers plopping ugly, oversized boxes into lots—but said the creativity championed by architects such as Frank Lloyd Wright and John Lautner would suffer.

“There have been abuses that led to the creation of this ordinance, but this ordinance goes so far in curtailing the abuses that it actually cuts into the creativity of design for the hillside areas,” said Litz, government affairs director for the association.

The ordinance also imposes a minimum unit size on lots in order to maintain consistent development levels and sets grading limits. A height limit will be set at 28 feet to 36 feet depending on zone and the slope of the roof, said Erick Lopez, a city planner in the planning department. Neighborhoods can also ease or increase restrictions to fit their needs.

The new regulations cap a five-year anti-mansionization effort by the city. In 2008, Los Angeles imposed similar restrictions on the flatlands.
“Hills are real important for the inspiration of people. So this will now protect (neighborhoods),” said Councilman Tom LaBonge, who introduced the original anti-mansionization motion in 2006. “This is long overdue. It has taken a long time.”

Regulations had been so lax in the hills that developers could legally build beyond what was physically possible, Lopez said.

“You could build a house that was actually larger than the lot itself,” Lopez said. “Realistically, no one ever built like that, but nonetheless you can see how that would cause a problem in terms of out of scale development.”

Neville Graham, a L.A. real estate agent who specializes in land sales, said he wished the ordinance had been more tailored to communities and less “draconian,” but is happy the process is finally complete.

“We all want to move forward. It’s great that it’s settled, because landowners now know what (the law) is,” Graham said.  

Speaking from a podium in the mayor’s press room, Carol Sidlow of the Bel Air-Beverly Crest Neighborhood Council championed the new restrictions.

“For the first time land will dictate what is built on it, not the other way around,” she said.

Reach reporter Andrew Khouri here.