What Elongation and Tensile Strength Says About your Commercial Roof

Question: What is elongation? What is tensile strength? Why are they important?

Answer: Elongation and tensile strength are important factors for the roof.

Elongation is essentially how far, in a percentage, at which a roof membrane will go from its initial state to its final state when pulling it. The best comparison is a rubber band – how far it will stretch is considered elongation.

Tensile strength is how much force is needed to actually break that rubber band once you stretch it far enough.

If you think of a roof, think of weathering – especially hail or those types of impacts. A function of elongation and tensile strength will allow the roof to absorb those impacts and not have failure. In addition, over the course of a day a roof can experience large temperature swings. Temperature swings can actually cause the roof to breathe and move in and out via the temperature change. The tensile strength and elongation having high values allows the roof to move and not fail due to the typical movement of the roof.