• Support type (one- or two-sided)
• Type of load (line or uniform, applied separately or in combination)
• Load magnitude
• Load duration (estimation of how long the load would be applied)
• Laminate dimensions
• Glass type (annealed, heat strengthened, tempered)
• Glass edge finish (clean-cut, seamed, polished)
• Upper use temperature (indoor/outdoor)

When these criteria have been entered in the web-based interactive tool, the values for glass stress, deflection and effective thickness are estimated. A slide-bar at the bottom of the screen can be moved to select different glass thickness values. The calculator is based on glass design principles embodied in standards that address glass strength, including American Society of Testing and Materials Association E1300, Standard Practice for Determining Load Resistance of Glass in Buildings, and prEN 13474, the developing norm published through the European Association of Flat Glass Manufacturers.

The tool compares values between a structural interlayer and PVB interlayer for different scenarios. In some situations, lower deflection and greater glass strength can be achieved with the use of the structural interlayer due to the slightly stiffer nature of the interlayer. The strength calculator helps users consider the relative influence of common laminated glass design variables, but final specifications for laminated glass used in construction projects should always be confirmed by qualified design professionals.