Mitigation credits are provided for houses with a Hip roof shape. Determination of the correct “Roof Geometry” takes an understanding of the “rules” that apply. The OIR 1802 form say: *Porches or carports that are not structurally connected to the main roof system are not considered in the roof geometry determination. *It further states: *Hip roof with no other roof shapes greater than 50% of any major wall length. *There is no “Official” definition of major wall length so we use the definition that has been used for the My Safe Florida Home Program and the one that has been accepted by many insurance companies: The “50% rule” refers to teh relationship of the gable bottom cord length vs. the wall the gable is above and/or sits upon.
The predominate Roof Geometry, that which is greater than 50% of the elevation, should be selected for that elevation. If an elevation has a Hip roof and it includes a gble and the total length of the gable borrom cord is greater than 50% of the wall upon which it sits, the elevation is classified as Gable. An elevation that has a Hip roof may also have more than one gable. If the gable bottom cord of any ONE of the gables is greater than 50% of the wall upon which it sits the Roof Geometry for the elevation is classified as Gable. When more than one gable is located on an elevation the lengths of the gable bottom cords are NOT to be added together in order to determine the greater than 50% rule. Even if a gable is less than 4’ high at its highest point and the gable bottom cord is greater than 50% if the wall upon which it sits, the elevation is classified as Gable.
Elevations which have gables that are less than 4’ high and have gable bottom cord lengths which are 50% or less than the wall upon which they sit, are NOT classified as Gable.
Note: The above rules apply when Gables are encountered with other Roof Geometrys also.
Hope this helps you.