Marc

Arizona ADU law (HB 2720) requires larger cities to allow an attached and a detached ADU. See sizes, setbacks, parking, rentals and fees.

Unpermitted ADU in California: built before 2020 without a permit? AB 2533 lets you legalize it. See who qualifies and how it works.

Can you sell an ADU separately? California AB 1033 lets cities allow it as a condo, but only by ordinance. See the conditions and process.

ADU impact fees: California exempts ADUs of 750 sq ft or less. See the thresholds, school fees, proportional charges and Washington’s cap.

Do ADUs need separate utility meters in California? What state law, your city and your utility each require, plus cost options.

ADU setback requirements compared: California’s 4-foot rule, Washington, Colorado and Portland, plus fire separation limits.

Can an HOA block an ADU? California voids most bans, but a 2026 ruling went the other way for a condo. See how states treat HOA limits.

Colorado ADU law (HB24-1152) requires metro-area cities to allow ADUs. See size, setbacks, parking, owner occupancy, fees and deadlines.

Oregon ADU rules under ORS 197A.425, plus Portland’s limits on size, height, placement and fees, including the SDC waiver. Sources linked.

Washington State ADU law lets you build two ADUs on most urban lots. See size, parking, fee and owner-occupancy rules.