Structure Height Limits: Honolulu vs Mililani Town
How do structure height limits rules compare between Honolulu, HI and Mililani Town, HI?
Mililani Town has fewer restrictions than Honolulu.
Honolulu, HI
Honolulu County
Honolulu County's LUO Section 21-4.60 sets maximum structure heights and building envelope plane rules, with residential districts capped at 25 to 30 feet under ROH 21-3.70-1.
View full Honolulu rules →Mililani Town, HI
Honolulu County
ROH Sec. 21-4.60 limits Mililani Town residential building heights to roughly 25 feet flat or 30 feet pitched, with HOA guidelines often further restricting visible bulk in this master-planned community.
View full Mililani Town rules →Key Facts Comparison
| Fact | Honolulu | Mililani Town |
|---|---|---|
| Typical residential max | 25 feet | - |
| Envelope plane | 30 feet | - |
| Primary section | ROH 21-4.60 | - |
| Residential companion | ROH 21-3.70-1 | - |
| - | - |
Highlighted rows indicate differences between cities.
Honolulu FAQ
How tall can I build a house in Honolulu County?
Most residential zoning districts cap structures at 25 feet under ROH 21-4.60 with a 30-foot envelope plane rising from the side yards. Apartment and business districts allow greater heights.
What is the building envelope plane?
A sloped imaginary plane rising from the side-yard property lines that limits how close tall portions of a structure can be to neighbors. ROH 21-4.60 uses a 30-foot envelope in most residential districts.
Mililani Town FAQ
Can I add a second story to my single-story Mililani home?
Often yes within height limits, but HOA design review may restrict placement, size, or require harmonized architecture.
Are rooftop solar arrays restricted?
Roof-mounted solar generally gets exceptions, but HOA guidelines may dictate panel orientation and visibility from street.
Compare other topics
See how Honolulu and Mililani Town compare on other ordinance categories.
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