What should the durometer (hardness) reading be for a setting block?

The appropriate durometer reading for setting blocks is crucial because it determines the material's ability to properly support and absorb stresses from the glazing units. The measurement of Shore A 85 + 5 indicates that the setting block has a hardness suitable for providing adequate support while still allowing for slight deformation under load, ensuring that the glass is properly seated without risking breakage or excessive stress on the frame.

A hardness rating within this range balances flexibility and firmness, making it ideal for the installation context. This ensures that the setting block can endure environmental conditions and mechanical loads without degrading quickly, thus contributing to the overall durability of the glazing assembly.