Roofing Terminology 101 – How well did you retain what you learned in science class?

As one of the national leaders in applying science to roofing, Simon Roofing has developed proprietary methods for analyzing and determining a roof’s remaining useful life. That way it can make a most-informed recommendation to customers as to whether a roof can be repaired or restored before going the route of a costly replacement.

Every day in Simon Roofing’s state-of-the-art laboratory, core samples of all types of roofing membranes from customers all over the country are tested – to ASTM standards – and compared to a comprehensive database of hundreds of new baseline roofing membranes, giving facility managers’ critical, objective information about the condition of their roofs.

Throughout our testing process, we use terminology that we’ve found to be foreign to some of our customers when used in the context of roofing, so we thought we’d share a few examples, along with descriptions of why each of them is important to roofing performance.

• Elongation refers to the amount of extension of an object under stress. It’s usually expressed as a percentage of its ability to be stretched or pulled without breaking compared to its original length.
• Tensile strength is the resistance of a material to breaking under pressure.

These are two fundamental, yet critical testing methods for all core samples because with any building, there will be natural shifting and moving. Along with the actual building moving, there will be expansion and contraction of the roof due to variation in temperature. Because of this movement, the roof must be able to stretch sufficiently to compensate for any expansion (elongation), while also being “tough” enough to resist any splitting (tensile strength).

• Puncture resistance is a measurement of the relative ability of a material or object to inhibit the intrusion of a foreign object.

It’s not uncommon for roofs to be subject to a barrage of flying debris during times of high winds or damaging hail. Puncture resistance tells us to what degree a particular material can withstand such elements.

• Permeance is the state or quality of a material or membrane that causes it to allow liquids or gases to pass through it.

This comes into play specifically with the waterproofing characteristics of materials used in roofing.

• Adhesion refers to the action or process of adhering to a surface or object.

When we talk about adhesion in roofing it typically deals with a material’s ability to withstand wind uplift, or over time, maintain an effective seal against the decking and strength in the seams of the membrane and flashings to provide adequate waterproofing.

These are just a sampling of terms used in our labs on a daily basis. We’ll revisit more of these roofing science terms in future blogs.