Do I Need Tempered Glass in Minimum Height Windows?

International Codes

• The International Code Council publishes construction rules that are used throughout the U.S. The first edition of the International Building Codes was published in 2000, but not all states use the same IBC edition. Some state and local authorities adopt one or more of the International Codes, and then create their own amendments. This results in many jurisdictions having their own variations of these particular codes. Checking with your local government can provide your locale's legalities for windows.

Hazardous Locations

• The 2006 version of the International Residential Code, R308.4, lists a variety of hazardous locations for panes of glass, which requires safety glazing such as tempered glass. Some hazardous window locations include an exposed area of an individual pane larger than 9 square feet, the bottom edge of a pane less than 18 inches above the floor, the pane's top edge is more than 36 inches above the floor or one or more walking surfaces is within 36 inches horizontally of the window.

Heat-Treated Glass

• Heat-treated glass produces safety features that include added strength, resistance to thermal stress and impact resistance. Heat-treated glass comes int two types: heat-strengthened and fully tempered. The heat-treating process creates an initial condition of surface and edge compression by heating the glass, then cooling the surfaces rapidly. The middle of the glass remains hot compared to the surfaces. Glass edges and surfaces are forced into compression as the center cools and thickens. Heat-strengthened glass isn't as impact-resistant as fully tempered glass.

Tempered Glass

• The safety characteristics of fully tempered glass make it ideal for residential windows. Fully tempered glass typically fulfills mandated requirements for windows. Safety comes from its fracture pattern and strength, which resists direct impact and strong wind. Fully tempered glass shatters into small, relatively harmless fragments called "dicing."