What is the minimum slope required for a roof when installing a skylight without a curb in Group R-3 occupancies?

For installing a skylight without a curb in Group R-3 occupancies, the minimum slope required is 14 degrees. This specification is critical to ensure proper drainage and to prevent water pooling on the roof surface around the skylight, which can lead to leaks and structural issues over time. A slope of 14 degrees allows for sufficient water runoff, which is essential in residential buildings where heavy rain or snowfall could otherwise compromise the integrity of the roof structure.

When choosing a slope, various factors such as local climate conditions and building codes must be considered, but 14 degrees has been established as a standard requirement to balance effective drainage while allowing for water runoff. The choice of not placing a curb adds complexity, as a curb typically elevates the skylight, allowing it to stand above the roof surface, which naturally enhances drainage. Without a curb, adhering to this minimum slope becomes even more important to mitigate potential water intrusion.