Volume 35, Number 2, February 2000
The Continuing Saga
field testing of windows and doors: a further look at air infiltration and water penetration causes
by Mike Mackareth
In a recent issue of USGlass a discussion was presented regarding the processes and pitfalls associated with bringing the redress of non-performance of installed fenestration products to a successful conclusion. Now that all of us are experts in determining which ASTM and/or AAMA documents are necessary to analyze each situation, an overview of the more common causes of air infiltration and water penetration is in order. Nothing presented here will be a startling revelation, but it is important to bring these issues to the forefront so we may reduce the number and extent of field related problems. This will promote customer satisfaction and a healthier bottom line.
Typically, problems associated with field installed products fall into three categories: product workmanship, installation workmanship, and adjacent wall construction workmanship. This discussion assumes that all design issues regarding fenestration products and adjacent wall construction have been corrected through the proper processes prior to the erection and installation of the project.
Poor product workmanship issues are the most readily recognizable and easiest to address. They are also the first to be blamed either with or without cause. Most issues with product workmanship deal with proper sealing of the product. Corner seals, appropriate weatherstripping (size and location), and dimensioning (sash size, squareness, etc.) are the most common sources of leakage associated with manufacturing defects. Proper in-house quality assurance is the most successful way of avoiding these issues. One other consideration is proper packaging and shipping of the final product.
We have all heard it before, The best window or door is no better than the quality of the installation of the product. Although this phrase has become trite with overuse, its meaning is just as important. The majority of the problems associated with a poor installation are the simplest to check. The product must be installed square and plum in the opening, in accordance with the manufacturers instructions and utilize the appropriate materials (sealants, fasteners, etc.). These problems can most readily be addressed by employing qualified, well supervised installation professionals. A pilot program designed by the AAMA for the training and registering of window and door installers is now underway. Programs such as this should significantly reduce problems associated with product installation.
Wall Construction Workmanship
Problems associated with the wall construction adjacent to installed fenestration products are perhaps the hardest to define, identify and repair. However, these problems consistently provide the most devastating effects on building performance. Improperly installed or non-existent flashing, blocked masonry weeps and incompatible sealants are some of the more common causes of air and water penetration. In most cases, the leakage created by these situations takes the path of least resistance into the interior of the building. As windows and doors provide the largest openings through the wall, the leakage routinely appears at these areas, thus providing misleading evidence of a fenestration product performance failure.
A systematic isolation approach using the appropriate test methods and standards identified in the previous publication is the most effective way to identify the probable causes of exterior wall leakage. This will allow all trades involved to successfully and efficiently identify problems, assign the proper assessment of responsibility, and evaluate effective repairs.
Reducing finger-pointing and blame by understanding the causes and proper steps for analyzing field problems, should be the aim of all responsible building and manufacturing professionals. As space and time restraints of this publication do not lend itself to an in-depth discussion of the factors promoting field problems of fenestration products, it should be the goal of all to become familiar with these problems. Only then can the proper handling of these unfortunate situations be a benchmark for separating the companies who will do business well into the future from those that will not.
Mike Mackareth serves as sales manager for Architectural Testing Inc. located in York, PA. Fenestration Focus appears monthly with rotating columnists.
© Copyright 2000 Key Communications, Inc. All rights reserved. No reproduction of any type without expressed written permission.