This zone accounts for about 5 of the roof surface represented the corners of the roof.
Wind uplift at parapet walls on roofs.
Used for roof overhang area along the perimeter of zone 2.
Improves wind uplift resistance wind is a major culprit for roof damages.
Used for roof overhang area along the perimeter of zone 3.
Parapetitus they have a long history which of course is not always clear that allows me to embellish without threat of peer review reversal.
Parapet walls can serve several purposes.
Wind damage to buildings is primarily caused by roofing damage under high uplift forces caused by wind action.
Any areas between the wall corners that are not included within zone 5.
Parapets are a combination of wall and roof pressures.
1 their major function today aside from confusing architects is to protect the edge of roof assemblies from wind uplift forces.
The exact height of the parapet is not factored into the roof wind uplift calculations but if the parapet is 3 feet or higher the perimeter values can be used at the corners lowering the uplift requirements for that portion of the roof area.
Historically so many problems have occurred with parapets that we have a name for it.
As wind flows over the building the pressure directly above the surface of the roof decreases.
Has the highest load.
Before we can answer the question however we must first define wind uplift.
Separation of air flow over the leading edge of building roofs causes the pressure.