Deflection
The design professional must consider deflection,
as well as strength, when specifying glass products
for any project. Excessive deflection at design
loads could lead to glass breakage, as well as being
objectionable to those working near the glass.
The dynamic and static loads (typically wind and
dead loads) acting on glass will cause it to deflect.
The amount and shape of the deflection depends
on the glass size and thickness, and the glass edge
support conditions, as well as the loads. The
glass and glazing system must be designed, not
only to have the strength necessary to withstand
the design load, but to also limit deflection to
an acceptable amount, as determined by the
design professional.
ASTM E1300 is the industry standard used for
determining the load resistance of glass in
buildings. It also includes information for
calculating the deflection of glass based on the
size and thickness of glass.
Window Glass Design software developed by the
Standards Design Group, Inc., is a program that
is used for determining the deflection of glass at
various design loads. Glass deflection and load
resistance values generated by this program
are based on the parameters in the ASTM
E1300 standard.
Example of Window Glass Design Input Screen
Example of a Window Glass Design Results Screen
