Virtually every building has window systems of some type, and architects spend a fair amount of time during the design process discerning the best choices for a particular project. Selecting and specifying windows and glazing certainly has a significant impact on the overall design and aesthetic of a building but equally important is the overall quality of the window system in terms of durability, weather resistance and physical integrity.

Further, in this energy-conscious era, the thermal performance of windows has become a major design consideration as well. Assessing all of these variables, particularly in commercial, industrial and institutional buildings usually comes down to three fundamental choices: storefront glazing systems, curtain wall systems or pre-glazed manufactured windows. Of course, there are also further variations to consider within each related to appearance, cost, customization, fabrication and installation.

Understanding the differences between these three choices and their respective strengths and weaknesses will allow architects to choose the most desirable and best performing system for an individual building design.

Characteristics of High-Performance Windows

By definition, high-performance windows need to perform better than conventional window systems. This applies in several ways. First their inherent internal structure must be adequate and appropriate to the installation and the wind, water, and other loading stresses it will encounter. Building codes usually dictate minimum performance requirements in this regard, but there can be many instances where a higher level of structural performance is required to provide greater protection against natural forces such as hurricanes or earthquakes or against man-made forces such as blast resistance.

In this low-rise building, the field-assembled curtain wall system provides superior performance compared to other choices. Photo courtesy of Manko Window Systems, Inc.