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Since ASCE 7 provides specific guidance only for symmetric buildings with two gable ends and two roof surfaces of equal slope, it is left to the discretion of the designer to apply the low -rise procedure to other geometries.
A warning appears if the building has unevenly sized stories, as these are not specifically addressed in the ASCE 7 but can be modelled as described in Building Model Assumptions. A warning also appears if hip ends are treated as a side panel (see below).
A warning appears if the building has:
as these types of buildings are outside the model described in ASCE 7.
No loads will be generated the building is over 60 ft in height, or the height-to-width ratio is greater than 1 as these are outside the definition of a low-rise structure in 26.2, or if it is an Open structure, as these are not allowed for the Envelope Procedure.
Hip Ends
The program allows you the option of implementing ASCE 7 figure C28.3-2 for wind loads on hip roofs. Note that with this model, for both load case A and load Case B, case A coefficients are used, so that Case A and Case B are identical in the transverse-to-ridge direction.
As some designers feel that this model does not generate realistic loads, you also have the option of treating hip ends as if they were side panels loaded in the transverse direction. A warning appears if there are hip ends and the special procedure in Figure C28.3-2 is not used.