Before You Build in Honolulu, HI: Permit & Rule Checklist (2026)

In Honolulu, fences six feet or under are generally exempt from building permits unless on a street corner or in a flood zone. Fences taller than six feet require a permit and fire-department access approval.

Honolulu's Land Use Ordinance limits residential fences to 6 feet in side and rear yards and 4 feet in front yards. Fences over 6 feet require a Department of Planning and Permitting building permit.

Honolulu's Land Use Ordinance (ROH Chapter 21) limits fences and walls to 6 feet in required yards. Fences taller than 6 feet or new fences costing over $1,000 require a building permit; shared boundary-line fences involve mutual consent and state cost-sharing law.

A building permit from the Honolulu Department of Planning and Permitting is required before constructing any residential swimming pool, under ROH Chapter 16, Article 6. Plans must be prepared by a licensed Hawaii engineer or architect.

Honolulu ROH § 16-6.2 requires all residential swimming pools to be enclosed by a barrier at least 48 inches high with self-closing, self-latching gates. The building code adopts ISPSC standards for gap clearance and non-climbable design.

Honolulu requires all residential swimming pools to be enclosed by a barrier at least 48 inches high with self-closing, self-latching gates. A building permit is required before construction. Non-compliant pools face penalties under ROH Chapter 16.

Honolulu treats above-ground pools the same as in-ground pools for safety. Under ROH Chapter 16, which adopts the Hawaii State Residential Code (IRC) and Hawaii Building Code Section 3109, any residential pool capable of holding more than 24 inches of water must be enclosed by a 48-inch barrier, with openings that block a 4-inch sphere, self-closing/self-latching gates, and only a 4-inch maximum gap between the pool wall and the barrier when the pool wall itself is used as the enclosure. Ladders or steps must be removable, lockable, or independently fenced. A building permit from DPP is required before installation of any pool deeper than 24 inches.

Honolulu's LUO § 21-5.720 allows garage and accessory structure conversions into accessory dwelling units in residential zones, subject to floor area limits, parking requirements, and a building permit from DPP.

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).

Honolulu allows one-story detached storage sheds of up to 120 square feet on residential lots without a building permit under ROH Ch. 18. Larger structures require a building permit and must conform to zoning setbacks under ROH Ch. 21.

Honolulu carports must meet the same Land Use Ordinance (LUO) yard setbacks as the main house unless the homeowner obtains a Zoning Adjustment under ROH §21-2.140-1. A one- or two-car carport may encroach into required front and side yards only if no other viable alternative exists relative to a dwelling legally built before October 22, 1986, or to lot topography, and the carport's horizontal footprint generally cannot exceed 20 feet by 20 feet. A DPP building permit under ROH Chapter 16 is required, and carports do not count as floor area for FAR purposes.

Honolulu regulates open burning under ROH Chapter 20 (Fire Code). Recreational, decorative, or ceremonial fires require prior written permission from the property owner and advance HFD approval; all fires must be reported to dispatch before ignition.

Honolulu regulates open outdoor burning under ROH Chapter 20 (Fire Code). Most open burning requires prior notification or written AHJ approval, and is prohibited when deemed a fire hazard.

Honolulu's Board of Water Supply (BWS) may declare mandatory water-conservation stages restricting outdoor irrigation timing and volume. The Land Use Ordinance also requires permanent irrigation systems for required landscaping on development sites.

Honolulu requires permits for trimming, pruning, or removing street trees in the public right-of-way (ROH § 10-1.4) and for any work on city-designated exceptional trees under ROH Ch. 40, Art. 8. Fines up to $1,000 apply for violations.

Honolulu protects designated 'exceptional trees' under Revised Ordinances of Honolulu (ROH) Chapter 40, Article 8. Removing or destroying any exceptional tree without City Council approval is unlawful (ROH § 40-8.8). Any pruning of branches or alteration of an exceptional tree's characteristic shape requires a permit from the Department of Parks and Recreation (Division of Urban Forestry). Street trees in the public right-of-way are City property and always require a permit.