Aerodynamic Mitigation of Roof and Wall Corner Suctions Using Simple Architectural Elements: Fid-Bau Portal

Aerodynamic Mitigation of Roof and Wall Corner Suctions Using Simple Architectural Elements

Bitsuamlak, Girma T. / Warsido, Workamaw / Ledesma, Edward / Chowdhury, Arindam Gan

Abstract

This paper presents the use of simple architectural elements such as aerodynamic mitigation devices for reducing high wind-induced suctions occurring at roof and wall corners of low-rise buildings where wind-induced building envelope failures usually initiate. The architectural elements considered in the current study include trellises (pergolas), roof extensions of gable ends (gable end ribs), ridgeline extensions (ridge rib), and sideways extensions of walls (wall ribs). A small-scale model of residential villa was tested in a boundary layer wind tunnel for two different roof geometries (gable and hip). Moreover, selected cases were investigated at the Wall of Wind, a large-scale testing facility, to investigate scale effects. The effectiveness of these architectural elements in reducing high suction (negative pressure) was assessed by comparing the wind-induced pressure measurements obtained before and after introducing the elements. Based on the results obtained for the worst wind angle of attacks, the peak suction was reduced after introducing the architectural elements by 65% at gable-end corners, 60% close to roof ridges, 45% at soffits, 35% at wall corners, and 25% at eaves. These simple architectural elements, which can be retrofitted to the stock of existing homes or incorporated into the design of new buildings, can be used as aerodynamic mitigation devices for reducing peak suction at critical locations of the building envelope.