ADU Rules: Ewa Gentry vs Honolulu
How do adu rules rules compare between Ewa Gentry, HI and Honolulu, HI?
Ewa Gentry and Honolulu have similar restriction levels.
Ewa Gentry, HI
Honolulu County
Ewa Gentry homeowners may build one accessory dwelling unit per zoning lot in eligible residential districts, subject to Honolulu LUO size, parking, occupancy, and rental duration rules under ROH Sec. 21-5.720.
View full Ewa Gentry rules →Honolulu, HI
Honolulu County
Honolulu allows one accessory dwelling unit on residential lots of 3,500 sq ft or more. Size is capped at 400–800 sq ft depending on lot size. Owner must live on the property and ADUs may only be rented long-term (six-month minimum).
View full Honolulu rules →Key Facts Comparison
| Fact | Ewa Gentry | Honolulu |
|---|---|---|
| - | - | |
| Minimum lot size | - | 3,500 sq ft |
| Max ADU size (small lot) | - | 400 sq ft (3,500–4,999 sq ft lot) |
| Max ADU size (large lot) | - | 800 sq ft (5,000+ sq ft lot) |
| Minimum rental term | - | 6 months (180 days) |
| Owner occupancy required | - | Yes — main house or ADU |
Highlighted rows indicate differences between cities.
Ewa Gentry FAQ
Can I build an ADU on my Ewa Gentry lot?
If your lot meets the minimum size for your zoning district (commonly R-5 or R-3.5) and you can provide parking, one ADU is generally allowed under ROH Sec. 21-5.720. Check your HOA covenants first.
Can I rent my ADU on Airbnb?
No. Rentals under 30 days are prohibited in ADUs citywide. Only monthly or longer-term leases are allowed.
Honolulu FAQ
Can I rent my ADU on Airbnb or use it as a vacation rental?
No. ADUs are expressly prohibited from being used as bed and breakfast homes or transient vacation units. All rentals must be for a minimum of six months under a written lease.
Do I need a permit to build an ADU or convert an existing structure?
Yes. A building permit is required. Structures built without a permit before September 14, 2015 may obtain an after-the-fact permit to be converted to an ADU.
What happens if I no longer live on the property?
The ordinance allows limited hardship exceptions (e.g., military deployment or serious illness). All other absences require the director's confirmation; failing to maintain owner-occupancy is a code violation.
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