Volume 6 Issue 5 June 2005
Verify Window Installation Practices Before Hitting the Filed
by Larry Livermore
A great deal of attention has been focused on window installation lately, even though installation has been recognized as the crucial focal point for delivered quality for some time.
It was this understanding that propelled the development of ASTM E 2112 as well as the Installation-Masters™ Program.
Keep Testing Real
But how can a manufacturer be sure that the installation instruction it specifies will be sufficient to ensure peak product performance? The key, as always, is testing to verify performance in conditions that accurately simulate the real-world environment.
Certification testing of product samples to 101/I.S. 2-97, 101/I.S. 2/NAFS-02 or the new 101/I.S. 2/A440-04 standards verifies the performance of the sample product itself.
Performance after installation can be checked according to the methods of AAMA 502-02, “Voluntary Specification for Field Testing of Windows and Sliding Glass Doors.” While the latter is useful for verifying air infiltration and water penetration resistance of newly installed products, it is of maximum benefit only when performed as soon as practical on the job site so that any manufacturing, installation and/or perimeter sealing problems can be detected and corrected before a substantial portion of the project is completed. But even this can delay construction and cost money.
Verifying installation methods earlier in the product delivery pipeline could help forestall such problems entirely. Manufacturers will soon be able to do just that and cite industry-recognized test results as proof. A new test method, now being finalized for publication, addresses the installation of windows, sliding patio doors and swinging doors used in residential or light commercial new wood-frame construction. It is intended for use in qualifying manufacturer-prescribed installation methods that do not follow well-established ASTM E 2112 or Installation-Masters procedures.
In practice, the method asks the manufacturer to send product (typically a flange-mounted unit) pre-mounted in a wall section of prescribed construction and dimensions per the instructions it intends to provide to contractors. The product is then tested as mounted.
To prepare for the test, a 4- by 4-foot window is mounted in the center of an 8- by 8-foot wall section constructed of a 2-by-6 outer frame with 2-by-4 studs within. The rough opening (RO) for the window unit consists of a double 2-by-6 header and a 2-by-4 sill plate, both supported by 2-by-4 framing. There must be a gap between the RO and the perimeter of the product of 3/8 inches to allow observation of any water leakage from the inside. The wall section may be sheathed with ˝-inch plywood or OSB or left open, but in either case covered with a weather-resistant barrier (WRB) per the manufacturer’s instructions or per Installation
Masters or ASTM E 2112 provisions as applicable.
The window chosen to fit the 4- by 4-foot RO must be a standard direct-set fixed window with an insulating glass (IG) unit (consisting of two lites of 3mm [DS] glass or other glazing with the same stiffness). Sealants used must meet applicable AAMA 800-92 requirements and applied per the sealant manufacturer’s instructions. Flashing must be installed per the InstallationMasters training manual, ASTM E 2112 or in the case of a material supplier in accordance with their prescribed instructions.
The test sequence begins with physical loading and temperature cycling conditions to simulate the actual in-service environment, then captures measurements of air infiltration and water penetration per ASTM E 283 and ASTM E 331, respectively. Air infiltration after durability stressing cannot exceed 0.10 cfm/ft2 per lineal foot of product perimeter, and there can be no water penetration through the installation system or into the wall cavity around the product perimeter.
Manufacturers interested in verifying installation instructions–and perhaps avoiding potentially costly problems in the field–may want to consider applying these tests. Final edits of the test method, to be known as AAMA 504, “Voluntary Laboratory Test Method to Qualify Fenestration Installation Proce-dures,” are now in play, aiming at a summer 2005 release.
Larry Livermore serves as technical standards manager for the American Architectural Manufacturers Association in Schaumburg, Ill.
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