Hawaii Administrative Rules
Title 3 - DEPARTMENT OF ACCOUNTING AND GENERAL SERVICES
Building Code Council
State Plumbing Code
AMENDMENTS TO THE 2018 IAPMO UNIFORM PLUMBING CODE
Definitions
1101.12.1 - Primary Roof Drainage

Roof areas of a building shall be drained by roof drains or gutters. The location and sizing of drains and gutters shall be coordinated with the structural design and pitch of the roof. Unless otherwise required by the authority having jurisdiction, roof drains, gutters, vertical conductors or leaders, and horizontal storm drains for primary drainage shall be sized based on a storm of sixty 60 minutes duration and 100 year return period. Refer to the National Weather Service rainfall map for 100-year, 60-minute storms at various locations.

Justification:

Section amended to reference the applicable Hawaii rainfall maps.