"Fenestration Beyond Standards
Successfully integrating windows, storefronts, and curtain walls
by David W. Altenhofen, CSI, CCS, AIA
Reprinted with permission of The Construction Specifications Institute
99 Canal Center Plaza, Suite 300, Alexandria, VA 22314, from The Construction Specifier

Construction phase

With the exception of chain stores and some residential work, virtually every project becomes a prototype with new and unique solutions. As such, , testing is a crucial part of the successful installation and long-term performance of windows, storefronts, and curtain walls. Large and complex projects require the construction of mock-ups at off-site laboratories. These mockups are rigorously tested per the specifications for conformance to the indicated performance criteria. On more typical projects, on-site testing to look for leaks and verify installation quality is important.

Even standard systems with performance proven through laboratory testing need field testing. Many systems depend on careful installation, and testing will determine whether the proper methods were used. Something as simple as a omitting dab of sealant at the corners of glazing gaskets, or not using calibrated torque wrenches for fasteners on a pressure plate can cause systemic failure. More importantly, the interface between the window and the adjacent wall needs to be tested. This joint is far from standard and is probably one of the most customized aspects of the building envelope.

Conclusions

All standards-details, test methods, specifications, and so forth-are useful tools, but on their own are incapable of delivering well-performing windows, storefront, and curtain wall systems. In fact, standards can become a crutch for the ill-informed or unqualified. Architects, specifiers, engineers, and other professionals must remember the purpose of the standards is usually to provide a scientific comparison method of performance criteria. Standard details are just the starting point for the proper integration of windows, storefront, and curtain wall systems.

Additional Information

Author
David W. Altenhofen, CSI, CCS, AIA, has over 20 years of architectural experience, and is a past chair of the national level, American Institute of Architects (AIA) Professional Interest Area (PIA) Committee on Specifications and Building Technology. He chairs a similar committee at the local Philadelphia, Pennsylvania, AIA chapter, and has presented at AIA's national convention. Altenhofen is a guest lecturer and critic at Drexel and Philadelphia universities, and has already published two articles in The Construction Specifier. He can be reached via e-mail atdaltenhofen@kling.us.

MasterFormat No.
08050-Basic Door and Window Materials and Methods
General Data-Specifications
General Data-Standards

UniFormat No.
B2020-Exterior Windows

Key words
Division 8
American Architectural Manufacturers Association
American Institute of Architects
American National Standards Institute
American Society of Civil Engineers
ASTM International
Construction Sciences Research Foundation
International Building Code
National Fenestration Rating Council
National Wood Window and Door Association
Southern Building Code Congress International

Abstract
All standards-details, test methods, specifications, and so forth-are useful tools, but on their own are incapable of delivering well-performing windows, storefront, and curtain wall systems. Architects, specifiers, engineers, and other professionals must remember the purpose of the standards is usually to provide a scientific comparison method of performance criteria. Specialized skill and knowledge are required to integrate windows into a building, and fenestration design should not be limited by standards.