IECC 2015 - Residential (Hawaii)

Last updated: 15 February 2019
Development Authority: International Code Commission and Architectural Energy Corporation of Hawaii

Implementation Authority: Municipal or county governments

Verification Authority: Code officials

Prescriptive Compliance path
The horizontal projection of that portion of interior space which is contained within exterior walls and which is conditioned directly or indirectly by an energy-using system

Energy Requirements:
U-Values (Btu/h.ft2) Floor Roof Walls Windows
Climate zone 1 0.064 0.035 0.197 1.2
Climate zone 2 0.064 0.035 0.165 0.75
Climate zone 3A and 3B 0.047 0.035 0.141 0.65
Climate zone 4A and 4B 0.047 0.03 0.141 0.35
Climate zone 4C 0.033 0.03 0.082 0.35
Climate zone 5 0.033 0.03 0.082 0.35
Climate zone 6 0.033 0.026 0.06 0.35
Climate zone 7 0.033 0.026 0.057 0.35
Climate zone 8 0.028 0.026 0.057 0.35

SHGC is 0.40 W/m2.k for zones 1 - 3 Up to 1.4m2 of glazed fenestration per dwelling unit shall be permitted to be exempt from U-factor and SHGC requirements
Skylights individually are 0.75 W/m2.k zones 1-2, 0.65 W/m2.k zone 3 and 0.60 W/m2.k zones 4-8
Air Leakage
0.3 cubic feet per minute (CFM) per square foot of door area for sliding doors 0.5 cubic feet per minute (CFM) per square foot of door area for swinging doors. For residences without mechanical ventilation > 0.35 ACH (model based approach only) For residences with mechanical ventilation measured air exchange rate combined with the mechanical ventilation rate > 0.01 × conditioned floor area + 7.5 × (Nbedrooms+1)
Space Heating System
At least one thermostat shall be provided for each separate heating and cooling system. Specific requirements exist for ducts, piping, ventilation, pool systems and snow melt systems Requirements are relative to equipment size and building type.
Water Heating System
All circulating service hot water piping shall be insulated to at least R-2 and have automatic or accessible manual switches to turn off the pump when the system is not in use
Compliance Softwares:
End-uses considered:
Space cooling, Space heating, Water heating, Ventilation
Performance Compliance path
Not a requirement / performance based elements are based on a reference model and are relative to energy costs

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