Accessory Dwelling Units

A two-story house with beige siding, white trim, and multiple windows during sunset, with a wooden fence and some plants in the yard.

Accessory Dwelling Units are a growing trend in California and throughout the USA. They are rentable units with a complete kitchen and bath that may be built on a typical residential lot or larger property as well on existing multi-housing properties.

ADU’s are allowed to be within an existing residence and identified as a Junior ADU or attached to an existing house or detached. An existing garage may also be converted to an ADU without having to build an additional garage.

We specialize in ADU’s and have a selection of standard plans ranging from 500 SF to 1200 SF that have been previously submitted. We also can design a custom ADU to meet your property characteristics or personal vision.

Use our Contact page to send us information on your property and the size of ADU your desire and we will get back to you with a quote.

Purchasable Plans page coming soon!

FAQ for California ADU

  • Can I build on a standard R-1 residential lot that has an existing or new single family home? Yes, but the size of existing home and size of lot may restrict the size and design gf the ADU.

  • Am I required to acquire a building permit? Yes, if property is in California you are required to submit plans for a building permit.

  • What is the cost of an ADU permit? This will vary based on your city or county, the value of your construction. Be aware as some cities add development fees for ADU’s more than 750 SF on top of the standard building permit fee.

  • What is the maximum size for an ADU? 1200 SF but may be less if the main dwelling is 1200 SF or less and some cities have additional restrictions . JADU typically are maximum of 500 SF.

  • Can an ADU be two story? Yes but some cities have restrictions.

  • Can I build an ADU with any architectural style? In many cases the government agency requires the ADU to match and complement the exciting house exterior style.

  • Can I have more than 1 ADU on my property? Yes, this falls under Bill SB9 and will typically require additional review by your Planning Dept. and added fees. This may include an attached JADU to the house or to the ADU as a second Unit. However, the size of your property may restrict this.

  • Can my ADU be connected to my existing septic? Yes but your septic system will need to be certified that it is capable to service the house and ADU. A new percolation test would be required to size the new tank and leach system per your property. We suggest this be done prior to hiring a designer. Property must be a minimum 1 acre lot for a standard septic. Under 1 acre requires an Advanced septic system which is exceedingly expensive.

  • Can I use my existing home’s electrical panel and meter to serve the ADU? Yes if it 200 Amp or more and can service a 100 amp sub-panel for the ADU.

  • Can I place the ADU on its own meter? Yes but some power companies require only one drop of service line to the property. If this is the case then you will have to replace the main panel to accommodate 2 meters to service the house and ADU separately.

  • Can I sell my ADU separate from my house? Yes, this falls under Bill AB1033. However there are a list of criteria that must be met. The most important requirement is that your city has adopted this allowance.

  • Do cities and counties provide ADU plans? Yes, the cost of the plans are in addition to your permit fees and varies on the city or county. However, those plans are typically not modifiable, will need to fit within the restrictions of your property and you will still be responsible to provide a site plan and Energy Compliance calculations.

Any further questions please call us as we are happy to supply further information to assist you with your ADU project.