D+AS MAGAZINE

TECHNICAL TIPS — ASK JOE HETZEL

© 2003 Door & Access Systems
Publish Date: Winter 2003
Author: Joe Hetzel
Page 60

ASK JOE HETZEL

By Joe Hetzel, DASMA Technical Director

Q: What if a building official enforces a wind load higher than the value shown in the DASMA wind load guides?

Joe: The local building official is the sole and final determiner of local code requirements. They usually do their best to understand, interpret, and enforce their applicable codes.

However, codes can be flawed. Codes may include requirements that are higher than needed. That’s because it’s sometimes simpler to require one conservative wind load value for all windows and doors on a building. Sometimes it’s because focused industry information is needed.

One recent example is in North Carolina, where the state residential building code has a garage door wind load table for its high-wind zone areas (110 mph and greater). However, the code does not have specific garage door wind loads for 90 and 100 mph wind zone areas. Code enforcers in these areas refer to a wind load table for “windows and doors” that have wind pressures far greater than those generally accepted within the industry.

In November 2003, DASMA contacted the North Carolina Building Code Council. We are working to resolve the problem with a short-term solution (recognition of a DASMA Garage Door Wind Load Guide) and a long-term solution (a code change proposal to incorporate a garage door wind load table based on 90 and 100 mph wind speeds).

So, to summarize, if an enforced garage door wind load exceeds industry determination for the load, a dealer should consider the following steps:

  1. Know the code being enforced and the code section(s) of note.
  2. Know what wind loads are being enforced.
  3. Contact your garage door manufacturer to explain the situation.
  4. Discuss with the manufacturer if it is a specific product-related or an industry-related matter.
  5. If an industry-related matter, encourage the manufacturer to get DASMA involved.

Q: What if a manufacturer supplies a dealer with testing based on a standard that is not in a building code?

JOE: Any standard used by a DASMA member and not in a building code must be evaluated for equivalency to a comparable standard already referenced in such code. If the standard is an industry standard that can be used by DASMA members, DASMA can evaluate it.

Recently, a Florida Building Code change affecting sectional garage doors inadvertently resulted in excluding recognition of ASTM E 330 as an acceptable alternative wind load test standard. DASMA prepared a document showing equivalency of testing to ASTM E 330 versus ANSI/DASMA 108. The Florida Building Commission reviewed the document and approved the equivalency.

The primary action for manufacturers is to test to standards referenced in building codes. If the industry commonly uses a standard to determine product performance characteristics subject to code compliance, that standard should ideally be incorporated into the code via the code change process.

If incorporating the standard is unsuccessful, or a short-term solution is needed, most building codes allow for an “alternate method.” The manufacturer must clearly show equivalency in terms of “quality, strength, effectiveness, fire resistance, durability, and safety.” The final decision on equivalency, however, rests solely with the local building official.