ASTM Standard E 2112 Enhances Exterior Building Installations
Correct installation of fenestration units is the best path to leak-free buildings. A new standard from ASTM International provides an understanding of water-shed systems in its advice for installing fenestration units in low-rise residential and light-commercial buildings.
Over 200 members of the building industry give clear instructions for complete integration of external wall components in ASTM E 2112, Standard Practice for Installation of Exterior Windows, Doors, and Skylights. The practice covers pre-installation through post-installation of single units or factory-mulled multiple units in a single opening. Developers of E 2112 familiarize users with the concepts of barrier systems and membrane/drainage systems to ensure the continuity of the building envelope.
Lacking a nationally-recognized consensus standard, the industry-group collaborated over four-and-a half years to create the comprehensive 89-page document that promotes:
Diminished water leakage, bug infestation, mold, or rot;
Enhanced durability and serviceability;
Minimized maintenance due to professional integration of products;
Stability of the thermal envelope for a more comfortable interior; and
Enhanced long-term building value.
By far, the most important application is the recognition that the wall is one envelope with many components; and there are different wall types which must be installed differently, says Barry Hardman, a building-envelope consultant from Temecula, Calif., who chairs the industry group. We can no longer treat each component separately, as if it lived in a universe by itself. It just makes sense that all areas which penetrate the wall must be correctly integrated. This includes everything, right on down to the faucet or cable TV wire. This standard addresses integration of windows, doors, skylights, flashing, anchors, shims, sealants, and building wraps. Hardman says E 2112 also covers:
Expansion, contraction, and building movement;
Compatibility of products;
Pre- and post-installation and stor age instructions;
Recommendations for adjustments and cleaning; and
The building wraps called for are rated by ASTM standards, and the size of overlaps and the size of building flashing components are called out, not left to the imagination of the unskilled installer, he adds. Sealant compatibility can be compared, and durability of the installation using those components can be evaluated.
Most manufacturers of exterior components dont supply instructions that adequately bridge their product to the wall, Hardman says, making it difficult for installers to determine their responsibility when joining components. Architects plans seldom address the complete integration of components, according to Hardman. For example, he says, who puts the sealant joint in between the window/door and the wall when required? The door/window installer? The siding installer? The general contractor? Houdini? And what about flashingswho supplies them? Where? Why? Who gives the flashing installation instructions and the wall construction sequences?, Hardman continues. Do you need to be trained in the art of origami to be able to install building wraps and flashings? Without these areas being adequately addressed, items such as variety in wall depths on one wall, inclusion of fireplaces, bay and bowed windows, and as the trade calls them, window pop-in and pop-out effects, have been part of a complex building envelope failure which ultimately causes catastrophic damage to the structure through the introduction of moisture. [This can] not only cause leakage to the interior, but create a breeding ground inside the wall for bugs, rot, and mold.
Experts who devised E 2112 include:
Forensic building experts who study sources of leaks and have either written widely or physically treat sick buildings;
Window designers and manufacturers familiar with a composite of materials such as wood, vinyl, aluminum, and pultrusion;
Designers and manufacturers of doors and skylights familiar with a composite of materials such as wood, vinyl, and aluminum;
Sealant, flashing, expanding-foam, glass, and weather-resistant barrier manufacturers;
Building code officials;
U.S. government officials (Department of Defense, Department of Energy, Department of the Interior, Forestry Products Division);
National organizations in related trades (American Architectural Manufacturers Association; Building Environment and Thermal Envelope Council; National Fenestration Rating Council; National Association of Home Builders; Window and Door Manufacturers Association; Society of the Plastics Industry; and Exterior Insulation and Finish Systems Industry Members Association);
Engineers, chemists, scientists for various related components; and
ASTM International issued Standard E 2112 in 2001. Primarily, the standard should be used as a learning tool to heighten the skill level of all installers, Hardman says. Since this document will be revised by ASTM approximately every two years, it will give the same authoritative group an opportunity to incorporate new materials and techniques as they evolve. Even the longevity of the building will be enhanced by eliminating construction defects. Would anybody mind if there were fewer lawsuits and better buildings?
The AAMA uses ASTM Standard E 2112 in a training program.The AAMA was an eager contributor to the creation of this document, Hardman explains. While E 2112 was in incubation, simultaneously AAMA created InstallationMasters (TM) certified-installer training, mirroring the techniques referenced in the ASTM standard. Both groups worked to make sure that the subject was correctly integrated between the two. The future should see the birth of more and more installation guidelines based on this document. We have seen already the Stucco Institute in Minnesota start to utilize parts of this procedure and incorporate them into their own instructions, thus extending the usefulness of both documents.
Direct comments to Barry Hardman, Temecula, Calif. Committee E06 meets April 6-9 in Kansas City, Mo. For meeting or membership details, contact Steve Mawn, manager, Technical Committee Operations, ASTM International (phone: 610/832-9726). //
Copyright 2002, ASTM
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