This law will lower the fees, perhaps by thousands of dollars, for an ADU if it is larger than 750 square feet.
Under a previous statewide law, builders (from large developers to individuals) would not be charged impact fees on an ADU that did not exceed 750 square feet. Impact fees are expenses a city requires to improve infrastructure needed for a new property, such as updates to roads, water and sewer systems.
To encourage more ADUs, the previous law prevented cities from charging impact fees — but there was a catch. If a builder went over 750 square feet, they would be charged all the impact fees for the original structure plus whatever they went over.
The new law now means that a builder will not have to pay anything on the first 750 square feet, even if they go over. Instead, they must only pay for anything more than 750 square feet.
One thing the law won’t do is create massive ADUs the size of high-rises because most jurisdictions have size limitations to begin with. Many communities limit the size of ADUs, still it is possible the average size of ADUs could creep up.
It is difficult to say across the whole region what cost savings the new law will bring because impact fees are different from city to city. Also, some cities have a host of exemptions for fees that further complicate an estimate.
Saad Asad, communications manager for pro-housing group California YIMBY, said it’s fair to say the law would likely save a builder “thousands of dollars” in fees.
