Ventilation Code Requirements in Hawaii

Hawaii Island (Big Island) is in SDC D due to volcanic activity. Other islands are SDC B/C.

All of Hawaii qualifies as a wind-borne debris region per ASCE 7-16 Figure 26.5-1C. Wind-borne debris protection is required for glazed openings in buildings located in wind-borne debris regions where the basic wind speed is 130 mph or greater, or within 1 mile of the coast. Given Hawaii island geography, virtually all developed areas qualify.

FEMA-designated Zone AE (Special Flood Hazard Area with established Base Flood Elevations) is present in all four Hawaii counties. Low-lying coastal areas, river valleys, and stream corridors are mapped as Zone AE. Significant areas include Waikiki/Ala Moana (Honolulu), Hilo Bay (Hawaii County), Kahului (Maui), and Hanalei/Kapaa (Kauai). Hawaii participates in the NFIP (National Flood Insurance Program).

Approximately 48% of all land in Hawaii is designated Conservation District, administered by the Department of Land and Natural Resources (DLNR) under HRS Chapter 183C. Conservation Districts include watershed areas, forests, natural reserves, and coastal zones. Hawaii's land use system is unique in the US - the State (not counties) controls Conservation District land use. Four subzones: Protective (P), Limited (L), Resource (R), and General (G).

All of Hawaii is classified as Seismic Design Category D (or higher for the Big Island) per ASCE 7-16. Hawaii experiences frequent earthquakes due to volcanic activity and tectonic movement. The 2018 Kilauea eruption sequence generated a M6.9 earthquake. The 2006 M6.7 Kiholo Bay earthquake caused significant structural damage on Hawaii Island. The 1975 M7.7 Kalapana earthquake generated a local tsunami. Big Island sites near active volcanoes may be SDC D1 or D2.

All of Hawaii is in a severe termite hazard zone. Formosan subterranean termites (Coptotermes formosanus) are the most destructive termite species in the United States and are well-established throughout Hawaii. Drywood termites (Cryptotermes brevis) are also prevalent. Warm, humid year-round climate provides ideal conditions for termite activity. Termite damage costs Hawaii property owners hundreds of millions of dollars annually. Hawaii has mandatory termite treatment requirements for new construction.

All of Hawaii is designated a hurricane-prone region per ASCE 7-16 Figure 26.5-1C. Basic wind speeds range from 105 mph (interior areas) to 130 mph (exposed coastal). Hawaii has experienced significant hurricanes including Iniki (1992, Kauai, 145 mph) and Lane (2018, Big Island). The Central Pacific hurricane season runs June through November.

All Hawaiian islands are subject to high wind design requirements with basic wind speeds ranging from 105-130 mph

FEMA-designated Zone VE (Coastal High Hazard Area with velocity wave action) is present along exposed coastlines of all four Hawaii counties. Zone VE indicates areas subject to coastal flooding with wave heights of 3 feet or greater. Particularly significant along north-facing shorelines exposed to North Pacific swells and areas facing prevailing trade wind waves.