The Impact of Wind Loads on Curtain Wall Design

Building facade is a major aesthetical feature of a particular building as it sets the
theme for the rest of the building. It introduces visitors and passersby to the identity
of the building and its characteristics distinguish one building from another. One of
the most common features of building facade is curtain wall. It carries its own dead
load and transfers the live loads that act upon it. A great knowledge and
understanding regarding forces and pressures which the curtain wall is subjected to,
may require a major attention when it comes to the design of curtain wall. The
primary concern is the dynamic or live loads that induce movement in the curtain wall
structure.
Comprehensive analysis of wind pressure acting upon a curtain wall seldom has been
practice in Malaysia. Generally, curtain wall design is under the concern of architect
whereby the wind pressure distribution acting on curtain wall is not well-predicted.
The design is more likely to be carried out based on a uniform wind pressure. On the
other hand, the assessment of curtain wall design shall be zoned based on the actual
design of known wind codes and standards, which is under the expertise of engineers.
This paper reviews and analyzes the impact of wind loads in designing a curtain wall.
In addition, it demonstrates an appropriate way in designing the wall glazing with
respect to the pressure distribution acting upon the curtain wall.
American Society of Civil Engineers (ASCE) 7-05 provides guidance in designing
wind loads for overall stability of a building, which encompasses the design for Main
Wind Force Resisting System (MWFRS) and Components and Cladding (C & Q.
Curtain wall is considered as a cladding system and hence, the analysis of wind loads
acting on it shall be done based on C&C procedures.
This paper distinguishes between two (2) approaches of curtain wall design, namely:
the proposed method based on the ASCE 7-05 versus the "traditional" method based
on the current consultancy practices in Malaysia. Subsequently, the cost impact of
both approaches had been analyzed by implementing Parametric Cost Estimate
Method.