Builders hoping to develop certain hillside properties in Los Angeles may have to reconsider their plans due to new zoning standards adopted by the city.

The new standards, which went into effect April 30, have created stricter setback rules for hillside properties located on “substandard” streets that don’t meet minimum city width requirements.

A hillside street is designated substandard when a portion of it is less than 28 feet across, the minimum width that the city’s zoning department deems necessary to handle emergency vehicles and a reasonable traffic flow.

In some hillside areas, the revamped setback rules will be enough to perhaps kill some projects or negate some lot sales.

That might have been the case for developers Wade Johnson and Kirk Rose, who rushed to submit plans to build two homes on Wattles Drive in Nichols Canyon under the pre-existing five-foot setback regulations once they caught wind of the zoning changes in March.

With the new standards, the projects would have needed setbacks of about 20 feet, which would have rendered their approximately 6,000- and 6,500-square-foot lots useless.

“We got lucky that we found out soon enough to respond, or we wouldn’t have been able to do the projects and we would have been stuck,” said Johnson, a construction and real estate attorney. “I think there will be a lot of screaming in the next couple of months. This will have a negative impact on lot prices. The more restrictions a piece of property has and the more expensive it is to build on it, the less desirable it becomes. Some people somewhere will be left holding the bag.”

“The primary goal of this was to make these areas safe for emergency vehicles like ambulances, fire trucks and police cars,” said Robert Janovici, L.A.’s chief zoning administrator. “In some areas of L.A., it’s hard to get emergency vehicles to a home because the streets are narrow and the houses come almost to the street. It had become an issue.”

It wasn’t until about 10 years ago that the city had any setback requirements at all, Janovici said. Until then, some hillside developments were built right up to the street.

Developers or property owners upset with the new regulations have a way to plead their case.

“They can apply for an adjustment,” Janovici said. “They can get a hearing with a zoning administrator and make their case, and they have ways to appeal that decision, too.