Within the past few years, ASCE 7, "Minimum Design Loads for
Buildings and Other Structures," published by the American Society
of Civil Engineers, increasingly has been used to determine design
wind loads, particularly because it is referenced in the 2000
edition of the International Building Code (IBC). Recently,
ASCE 7's 2002 edition became available; it is referenced in IBC's
2003 edition. Because many jurisdictions soon may begin requiring
compliance with IBC 2003, it is important you are aware of the
changes in ASCE 7.
ASCE 7's new edition includes several changes and additions that
apply to the calculation of roof assemblies' wind loads.
Unfortunately, the changes are not delineated in the document, and
it is a laborious process to determine what changes were made. I
tracked the changes, and following is an overview of those
pertaining to calculating roof assemblies' wind loads.
(Note: Additions and changes pertaining to primary
structural elements, such as beams, columns, shear walls and
diaphragms that provide support and stability for the building, are
not addressed in this article.)
220.127.116.11 is a new section pertaining to parapet loads. This
section directly applies to loads on parapet base flashings, which
previously were not addressed in ASCE 7. When determining base
flashing loads, the suction pressure on the windward parapet's roof
side is determined by using the same coefficient used for
To read the article in its entirety, please log in or register (registration is free).
Log in or register for FREE access to this article and other Professional Roofing online content.