©
2004 Door & Access Systems<br>
Publish Date: Spring 2004
Author: Joe Hetzel
Page 68
ASK JOE HETZEL
Q: “I’m considering adding some struts
and other measures to strengthen my garage door. What do you
recommend?”
Joe: Homeowners occasionally ask me this
question. I advise against such work, warning them about serious
safety concerns and how additional weight affects the counterbalance
system.
As door dealers know, the spring system may be unable to
handle the added weight. As a result, the spring could break,
or the spring’s support hardware could loosen. More
importantly, if a spring system’s stored energy is released,
anyone near the spring system could be seriously injured or
killed by flying parts.
So, I always tell them to contact a local trained door systems
technician to evaluate the door for a safe, effective repair
or to replace the door itself.
Q: “I hear that other organizations besides
DASMA are involved with the thermal performance of garage
doors and rolling doors. What is DASMA doing about this?”
Joe: You’ve heard right. A lot is happening,
and we’re involved on several levels.
- Testing. Historically, DASMA has published
testing criteria for thermal transmittance (U-factor) and
air infiltration in the standard ANSI/DASMA 105. However,
other organizations such as the National Fenestration Rating
Council (NFRC) and American Society for Testing and Materials
(ASTM) have published a different method of testing for
U-factor.
- Simulation. The NFRC has published a
standard that determines U-factor by “simulation”
(i.e., calculation using software) of various fenestration
(window, door, skylight) products. They have applied this
simulation method to garage doors and rolling doors.
- Research. ASHRAE, an association of
heating and air conditioning engineers, is currently conducting
a research project on the thermal performance of various
door products including garage doors and rolling doors.
DASMA is serving on a subcommittee that is monitoring that
project.
- Standards. NFRC and ASTM have published
standards for determining U-factor and air infiltration,
and they have included garage doors and rolling doors in
the scope of those standards. DASMA, however, has its own
standard: ANSI/DASMA 105.
- Code Content. NFRC standards that include
garage doors and rolling doors are currently referenced
in the International Residential Code and the International
Energy Conservation Code.
- Default Values. ASHRAE publishes tables
that show default U-factor values for certain garage door
and rolling door products.
- Labeling. NFRC has a labeling program
for fenestration products that can be construed as applicable
to garage doors and rolling doors. However, the program
has historically not applied to our products.
DASMA is monitoring all this activity, and we are actively
representing industry interests. In the end, we seek a reasonable,
fair, and accurate means of determining, reporting, and (when
required) regulating garage door and rolling door thermal
performance. We’ll keep you informed of our progress
through this magazine. |