Wind Uplift At Parapet Walls On Roofs

Parapetitus they have a long history which of course is not always clear that allows me to embellish without threat of peer review reversal.

Wind uplift at parapet walls on roofs.

As wind flows over the building the pressure directly above the surface of the roof decreases. Roof damage caused by wind occurs when the air pressure below the roofing assembly is greater than the air pressure above the building s roof. Before we can answer the question however we must first define wind uplift. Used for roof overhang area along the perimeter of zone 2.

This zone accounts for about 5 of the roof surface represented the corners of the roof. 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. Has the highest load. Any areas between the wall corners that are not included within zone 5.

Separation of air flow over the leading edge of building roofs causes the pressure. Fire protection as the wall is extended past the roof plane the parapet wall prevents flames from coming up through the exterior. Used for roof overhang area along the perimeter of zone 3. Parapet walls can serve several purposes.

1 their major function today aside from confusing architects is to protect the edge of roof assemblies from wind uplift forces. Improves wind uplift resistance wind is a major culprit for roof damages. Parapets are a combination of wall and roof pressures.