Ask Joe Hetzel: Questions for the DASMA Technical Director
© 2001 Door & Access Systems
Publish Date: Summer 2001
Author: Joe Hetzel
Page 42
TECHNICAL TIPS
Ask Joe Hetzel
Questions for the DASMA Technical Director
The Better Building Code?
Question: Which is better: Building codes that tell you how to build a product, or codes that tell you what the product should do?
Joe: For many years, building codes consisted primarily of “prescriptive” provisions. In other words, they gave specific parameters governing how products should be built. Codes have also allowed a product to be approved based on “performance” or on how it performs according to certain product-specific objectives.
The argument against a prescriptive provision is that it inherently may not allow for alternative products that achieve the same intent. Conversely, the argument against performance provisions is that products may be approved under criteria that may be too lenient or unproven.
Fortunately, modern codes have clearer, more-concise options so that products may comply with either prescriptive or performance-based criteria, at the choice of the manufacturer. When considering which method of compliance is more appropriate, the manufacturer may consider the product’s design, installation, and field application.
Example: Insulation
Take the new International Building Code for example. DASMA successfully incorporated provisions ensuring that manufacturers of garage doors containing foam plastics may choose to comply with either performance or prescriptive-based requirements.
In this case, the product can comply if the foam is covered by a minimum material thickness, such as .010-inch steel. But the doors may also comply by being tested to ANSI/DASMA 107, which is a full-scale fire test.
Example: Pinch Resistance
Another example is found in DASMA 116, the standard for section interfaces. Manufacturers can comply using prescriptive-based means (if the interface meets certain opening-oriented criteria) or with performance-based means (if a certain probe can be removed from the interface).
Example: Steel Gauge
DASMA is also continuing to evaluate existing prescriptive requirements in building codes. We’re exploring the idea of incorporating performance-based requirements based on sound research and testing.
One current situation involves minimum garage door steel gauge thickness requirements in the South Florida Building Code. These minimums were established based on forced entry situations.
DASMA is now doing research that may result in a DASMA standard that allows a garage door to be tested to certain forced entry situations. Hopefully, this will demonstrate that certain performance criteria can be met instead of a prescribed minimum gauge thickness.
“Performance-based” codes are now being developed in the U.S. and Canada. These codes should encourage alternate or innovative products, methods, and systems, yet provide for reliable means of proving needed integrity. Through examples like the ones cited above, DASMA will continue to work for the most appropriate means of achieving product compliance.