Before revision: "The Evils of Ponding Water" October 31, 2009, by Paul Graham According to the 2009 International Building Code Chapter 15 "Roof Assemblies and Roof Top Structures" & Chapter 16 "Structural Design"; " When scuppers are used for secondary (emergency overflow) roof drainage, the quantity, size, location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed ... Ponding instability.
After revision: The Evils of Ponding Water" October 31, 2009, by Paul Graham According to the 2009 International Building Code Chapter 15 "Roof Assemblies and Roof Top Structures" & Chapter 16 "Structural Design"; " When scuppers are used for secondary (emergency overflow) roof drainage, the quantity, size, location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed ... Ponding instability.