I have recently noticed that more of the jobs I have been reviewing, where glass railings on the roof of a building have combined loads of roof and wall loading. I understand the concept behind designing the physical parapet in this manner, but I do not understand using the same loading for a railing that is attached on the interior side of the parapet. Because of the gaps in the glass as well as the gaps in the glass shoes that are attached to the wall, I don't see how the leeward and windward pressure stack. Has anyone else encountered issues similar to this? the designs of the glass railing on the roof have gone from 1/2" laminated tempered to 13/16" laminated tempered or even thicker. I have read through the ASCE 7 code, but any additional insight would be greatly appreciated.
thank you.
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Chris Zambrano A.M.ASCE
Structural Engineer
Carlstadt NJ
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