To maintain the aesthetics of a new roof design, building owners often choose to conceal their rooftop mechanical equipment with screen walls. Screen walls are considered “architectural walls,” and are typically constructed using steel frames and finished with metal wall panels.
While aesthetics are an important consideration for screen wall design, building owners and designers should not overlook wind loading while selecting metal wall panels for their screen wall. Metal wall panels are often secured to a solid substrate, such as a masonry wall; however, wall panels attached to exposed steel framing (vertical posts and horizontal channels) in screen wall applications typically leave the back side of the panels open and exposed to wind. Wind can create a negative pressure acting outwards from behind the panel. This wind load pressure can cause panels to bow, allowing the connection between panels to disengage. When selecting metal wall panels for a rooftop screen wall, consider the following parameters:
- Panel Width: Increasing the width of a metal wall panel increases the surface area on which wind loads are applied. Selecting narrower metal wall panels helps to mitigate the effects of negative wind loading pressure.
- Panel Material: Many manufacturers offer metal wall panels in a variety of materials including aluminum and steel. Thicker gauge material with higher tensile strength will reduce the tendency for panels to deform under negative pressure.
- Panel Profile: Metal wall panels come in a variety of profiles: panels typically consist of two engagement legs on either side of the panel that interlock to form a connection between adjacent panels. Panels with longer engagement legs will provide for a deeper connection between adjacent panels, limiting the possibility of this connection to be compromised under wind loads.
Installing metal wall panels on a rooftop screen wall can improve building aesthetics; however, without proper consideration of wind loads, these panels are susceptible to damage. Selecting metal screen wall panels of an appropriate width, material, and profile to withstand wind loading pressure will help the panels to remain secure throughout the life of the roof.