- Manufacturer participation in a follow-up inspection and labeling certification program such as those conducted by UL, WHI, AAMA, NWWDA, etc.
- Copy of a test report from an approved independent testing laboratory indicating the tested design pressure rating of the unit.
- A North Carolina registered Professional Engineer's report summarizing the information from an independent laboratory, indicating the design pressure rating of the unit.
All three of the above documentation methods rely on a
properly performed test of
the product being certified. The test used in
determining the design pressure of doors and windows is
ASTM E-330. In this test, the specimens are not only
subjected to the desired design pressures, but also to
what is known as structural test pressure. The
structural test pressure is 1.5 times the design
pressure and acts to provide a safety margin.
Products are tested and reported as assemblies including
items such as mullions, astragals, hardware, seals, etc.
Only those components tested, approved and documented by
one of the three methods above can be used in the
installation of those products.
To
understand how the code requirements will affect the
design/construction phases of a new structure, consider
the following example:
Suppose a residential building having a mean roof height
of 25 feet is being built on the Outer Banks. Looking at
the Basic Wind Speed Map in the residential code, Figure
301.2b, we determine that the basic wind speed is 110
MPH. Next, referring to the table of Section 4002, we
find that a building with a 25' mean roof height located
in a 110 MPH wind zone requires doors and windows with a
design pressure rating of 40 PSF. We must now find
window and door products that have a design pressure
rating equal to or greater than 40 PSF and that have
proper documentation certifying their design pressures.
These documents would then be provided to the local
building departments to obtain proper building and
occupancy permits. If the building under consideration
had been a commercial application, then ASCE 7 methods
would have been used to determine the design pressure
requirements for the building and its components, rather
than using the table in Section 4002.
While all of this may seem a bit confusing,
there are a few simple things to keep in mind
when dealing with the code requirements
pertaining to side hinged doors, garage doors,
and windows:
- Know the design pressure
requirements of the building you are
constructing or supplying products to. You
may get this information from the NC
building code, from a professional engineer,
or possibly from a local building
department.
- Know the design pressure rating
of the products being used in the
construction of your building. The design
pressure rating must meet or exceed the
design pressure requirements of the
building. Always ask for the design pressure
rating; do not accept structural test
pressure figures as design pressure rating.
- Make sure the products you are
using have the proper documentation to
certify the design pressure rating of the
product.
For More Information:
For information particular to North
Carolina Hurricane Code and Insurance
Coverage contact:
North Carolina Department of
Insurance- (919) 733-3901
- American Society of Civil Engineers-
(212) 705-7496
ASCE 7-98 Standard
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