Components and Cladding: Gable with Parapet

[butch81385]

I was looking through ASCE 7-05 at the Components and Cladding for Gable Roofs with Theta <= 7 (pg. 56, figure 6-11B). Note 5 states the following:

5. If a parapet equal to or higher than 3ft is provided around the perimeter of the roof with Theta <= 7, the negative values of GCp in Zone 3 shall be equal to those for Zone 2 and positive values of GCp in Zones 2 and 4 shall be set equal to those for wall Zones 4 and 5 respectively (i)n Figure 6-11A.

I understand the first comment that you use Zone 2 for Zone 3. However, the next comment has me slightly confused. I read it that you should take Zone 2 (on the roof) and use the value from Zone 4 (on the wall). That makes enough sense. But then it says to take Zone 4 (presumably on the wall?) and use Zone 5 (also on the wall?). I would not have second guessed this except that the positive values for Zone 4 and 5 are both the same in the referenced figure. I figured there is an error or something I am missing since they wouldn't really tell you to change it to the same value, would they?

Any guidance would be helpful.

 

[Den32]

I would think this is a typ-o and should be "Zones 2 and 3 shall be set equal to Zones 4 and 5 respectivley" - that makes more sense.

I didn't see it in the Errata though? Unless there is a more recent errata?

http://www.seinstitute.org/pdf/erratasheet7-05.pdf

 

[butch81385]

Den, I agree fully. My first thought was, as you said, a typo of "4" instead of "3", but did not see it in the errata.

I guess I was hoping for any concrete confirmation (errata, published journal, etc) to back up what I do. Zones 2 and 3 do make the most sense as they would correspond with the parapet wall above zones 4 and 5.

For now I will use it in this way, but please share any other comments!