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What Are The New 2020 ADU Laws?

Updated: Jan 26, 2022

In September 2020, a new California Department Of Housing handbook regarding laws, rules, and regulations of newly built ADU’s was released. This article regards the laws of only the state of California, other states may be different.

There are not that many requirements for building a new ADU in CA, but the California Department of Housing And Community Development do require a few things for your newly built ADU to be up to code. The living room/bedroom needs to be at least 70 square feet.The kitchen (along with the hallways and closet) must measure in at 50 square feet.The bathroom must be at least 30 square feet and contain a toilet, sink, and a shower stall or tub. Your newly built ADU has to be less than 16 feet tall. And if your ADU is below that 16 foot height and is under 750 square feet, its building permits can’t be blocked. If you’re building an ADU within a home or existing building, the ADU can max out at the maximum height of the existing structure. The size of your ADU is important, but just as crucial are the materials you use to build it. There are critical standards to ensure that ADUs represent high quality housing options.

Builders can not use single piece composite, laminates, or interlocked metal sheathing. As for the roof, it can’t be made of wooden shingles. It must also have a minimum of a 2:12 pitch for greater than 50 percent of the roof area. Windows must be at least double-pane glass and labelled for building use, and they can’t have exterior trim. Newly constructed ADUs are subject to the Energy Code requirement to provide solar panels if the unit is a newly constructed, non-manufactured, detached ADU. The California Energy Commission states that the panels can be installed on the ADU or on the primary dwelling unit. ADUs that are constructed within existing space, or as an addition to existing homes, including detached additions where an existing detached building is converted from non-residential to residential space, are not subject to the Energy Code requirement to provide solar panels.

Roof installs will be the most common because it’s the area on your ADU that provides the greatest access to sunlight. If you own a piece of property that has a lot of land, you have another option. You can install your photovoltaic cells somewhere else as long as nothing is in the way of the solar panels. You can also choose to hire an alternative solar energy provider. In that case, you essentially rent out your roof to a solar company. Completely free of charge, they come and install solar panels on your roof. You then pay them for your monthly power bill, just as you pay your current energy provider. Instead of paying money to the power company, you pay the solar company.

Setbacks are also new necessary parts of building an ADU. Setbacks are the required space between a structure and your property line. These zoning rules are in place for your safety and to allow for proper light and air access between you and your neighbors. Setbacks are made for things like fire safety.The housing authority can impose development standards, such as setbacks, for the creation of ADUs. Setbacks may include front, corner, street, and alley setbacks. Additional setback requirements may be required in the coastal zone if required by a local coastal program. Setbacks may also account for utility easements or recorded setbacks. The housing authority also allows the expansion of a detached structure being converted into an ADU when the existing structure does not have four-foot rear and side setbacks. It is also legal for the expansion area of a detached structure being converted into an ADU to have no setbacks, or setbacks of less than four feet, if the existing structure has no setbacks, or has setbacks of less than four feet. In the typical single family home in California, the setbacks that matter most for an ADU are your side and rear yard setbacks. The rule in California according to the handbook is that the ADU must be 5 feet from the side and rear property lines.

There is not a minimum lot size requirement for an ADU. While state governments can have standards for ADUs, these standards can’t include minimum lot size requirements. But, building and safety standards are still in play and ADUs must adhere to those laws.the government can establish minimum and maximum size requirements for ADUs. However, maximum unit size requirements must be at least 850 square feet and 1,000 square feet for ADUs with more than one bedroom. For cities without an ordinance, maximum unit sizes are 1,200 square feet for a new detached ADU and up to 50 percent of the floor area of the existing primary dwelling for an attached ADU (at least 800 square feet). The conversion of an existing ADU or primary residence to a new ADU is not subject to size requirements. For example, an existing 3,000 square foot barn converted to an ADU would not be subject to the size requirements. If you want to expand your ADU in any way, then you may be subject to the size requirements.

Old laws on ADU ownership in California designated that ADU rights were tied to the primary residence. The ADU was not considered a property in its own right, but rather a unit that was part of the primary residence on the lot. It could not be sold separately from the primary residence, and if the primary residence transferred hands, so did the ADU. Under the bill AB 587l, ADUs may be bought or sold separately from the primary residence if certain conditions are met. Affordability restrictions are also placed on the sale and deed of the ADU ensuring that it remains preserved as affordable housing for low-income families for 45 years.

In addition, under an already existing tax law, property owned and operated by a nonprofit organization can qualify for a welfare exemption from property taxes.The idea is to increase the ability of affordable housing organizations to sell deed-restricted ADUs to low-income homeowners, allowing for shared ownership models that would increase the availability of affordable housing in California. Many HOAs have conditions, covenants and restrictions that prevent people from building ADUs. HOAs may worry about the design of the properties if one has an ADU on it, or they might be concerned that they don't know who is and who isn't renting from an ADU. Regardless, HOAs now need to have a way for people to construct ADUs if they so choose. AB670 is fixing this by restricting an HOA’s right to deny a homeowner wanting to build an ADU in California.

The California Department of Housing is prohibited from creating development standards for ADUs requirements on minimum lot size. Your ADU has more freedom and a custom build is more possible due to the new laws. Clarified areas designated by the department of housing for ADUs may be based on the adequacy of water and sewer services as well as impacts on traffic flow and public safety. This means that if there is enough sewer and water services in the area, your ADU will be much more likely to be approved. All owner and occupancy requirements for newly built ADU’s will be eliminated by the department of housing between January 1, 2020 and January 1, 2025. The housing authority also prohibits a local agency from establishing a maximum size of an ADU of less than 850 square feet, or 1,000 square feet if the ADU contains more than one bedroom and requires approval of a permit to build an ADU of up to 800 square feet.Before the 2020 rule changes, the approval period for ADUs was 120 days. Now, cities in California must provide approval or denial of the request within 60 days of receiving the application. Also, due to the 2020 ADU rule changes, HOA’s can not reasonably prohibit the development of ADUs or JADUs.

Neo Builders Inc. is an experienced construction company with a specialty in building ADU’s. Building an ADU with Neo Builders will increase your monthly cash flow in a stress free and organized process. Check out our Los Angeles rules and regulation page for more details.

Don’t wait, make the call today for a step towards financial freedom. An initial consultation and quote are FREE of charge.

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NEO Builders Inc.

3940 Laurel Canyon, Studio City #394, 91604

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