ParcelSheet

TMK guide · Land rules

ʻOhana units and accessory dwelling units

A second, smaller home on a lot. Each County writes its own rules.

An ʻohana unit or accessory dwelling unit, often called an ADU, is a second, smaller home on a lot that already has one. Each County sets its own rules in its zoning code, and they differ on size, parking, owner occupancy, and the zoning districts where a second unit is listed.

Whether a second unit can be built on a given lot depends on the zoning, the lot size, water service, wastewater, and in some areas the road. A cesspool lot or a lot in a flood or shoreline area may face extra steps.

ParcelSheet reads what the County code lists for the lot's zoning. It does not decide whether a project is approved; the County does.

What the law says, and who keeps it

What the ParcelSheet card shows

What the County code lists for adding to this lot, such as a second unit or a guest house, with the code section linked for each line.

Who to ask

The County Planning Department, and the water and wastewater agencies, before any design work.

See it on a real lot

Checked 2026-10-17. This page explains a term in plain words. It is not legal advice; the County or State office named above decides.

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