Washington Accessory dwellings (HB 1337, 2023): what it allows on a lot
Accessory dwellings (HB 1337, 2023) is Washington law, and the official source is at app.leg.wa.gov.
Cities and counties planning under the Growth Management Act must allow two accessory dwellings on most lots with a house in urban growth areas.
Whether it applies to one lot turns on where the lot is and what it is zoned; the city, county or state office named in the law decides. Mapped areas are approximate. This is a plain reading of public law with its source, not legal advice.
Free, no account. ParcelSheet shows the lot's mapped size, parcel lines and flood zone, and this law on the lot's Washington sheet.
Other Washington laws on a lot: Critical areas.
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