What Can You Use an ADU For? Rent, Family, Work

Updated October 2026

An ADU is a full second home on your lot, with its own kitchen, bath and entry. You can rent it, house family in it, or work from it. A few rules decide which.

The short version

• Long-term rental is the most common use. Cities can require rentals of 30 days or longer.
• No owner-occupancy rule for ADUs. AB 976 made that ban permanent from January 1, 2024. You can rent both the house and the ADU.
• A JADU (up to 500 sf, inside the main house) is different. If it shares a bathroom with the house, an owner must live on the property.
• You can’t sell an ADU separately unless your city has opted into AB 1033.

Common uses

• Rental income. Rent helps carry the mortgage. FHA lenders can count up to 75% of an existing ADU’s estimated rent toward a buyer’s income.
• Family. Adult children, parents, or a caregiver close by but with their own door.
• Aging in place. Build a single-level unit, move into it, and rent or hand over the main house.
• Work. A studio or office with a real separation from home. Check your city’s home-occupation rules if clients visit.
• Guests. Fine for visitors. Paid stays under 30 days may be barred by your city.

What to watch out for

• Plan for the hardest use. A unit designed for rent works for family. A home office often can’t become a legal rental without a kitchen and egress.
• Rent control. Some ADUs fall under local rent rules. Check before you set rent.
• Permits. Use of any kind starts with a permitted unit. See our legalization guide.

How we use it

Two households on one lot is the idea behind Foothill Residence: a 2-bed unit with a garage on the ground floor and the residence above. At Beaver Live Work in San Bernardino, a long gable home holds a work studio. If your lot can take more than two homes, see SB 684 / SB 1123.

Sources: Burke, Williams & Sorensen on the 2023 ADU laws, HCD ADU page.

From our portfolio

Foothill Residence

A home and a second household, stacked on one lot.

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