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Hawaii County Energy Code Bill Annotated Draft 11/27/19 improved blades would still befar from code compliance. Given Hawai'i's mild climate, the energy impact of reducing or eliminating air conditioning may far exceed the impact of additional heat gain. C. Hawai'i County Justification: as written, the State ofHawai'i does not qualify for the north exception. By removing the latitude requirement, Hawai'i County allows the exception. (12) A new subsection C402.4.3.5 is added to the International Energy Conservation Code to read as follows: "C402.4.3.5 Area-weighted SHGC. In commercial buildings, an area-weighted average of fenestration products shall be permitted to satisfy SHGC requirements. Exception: Jalousie windows are exempt from SHGC requirements." Comments: A. State Justcation: Modeling by the National Renewable Energy Laboratory (N-REL) indicated that shading fenestration was as effective as solar heat gain coefficient(SHGC) requirements in Hawai'i's mild climate. Area weighting allows trade-offs between fenestration SHGC allowing a higher SHGC to be installed on the North elevation and offsetting that with lower SHGC requirements for windows on the East, West and South. See: State ECC at§3-181.1-10, HAR. B. State Justification.- Jalousie windows are popular in Hawaii as an extremely effective means of passively cooling buildings by reducing or eliminating the need for air conditioning. The SHGC of the individual jalousie blades can be slightly improved, but only at great expense and the improved blades would still befar from code compliance. Given Ilawai'i's mild climate, the energy impact of reducing or eliminating air conditioning may far exceed the impact of additional heat gain. (13) Subsection C402.5 of the International Energy Conservation Code is amended to read as follows: "C402.5 Air leakage-thermal envelope (Mandatory). The thermal envelope of buildings shall comply with Sections C402.5.1 through C402.5.8, or the building thermal envelope shall be tested in accordance with ASTM E 779 at a pressure differential of 0.3 inch water gauge (75 Pa) [E)f an equivalent method approved by4he eode offieial] and deemed to comply with the provisions of this section when the tested air leakage rate of the building thermal envelope is not greater than 0.40 cfm/ft2 (0.2 Us - m2). Where compliance is based on such testing, the building shall also comply with Sections C402.5.5, C402.5.6 and C402.5.7." 12