The science of roofing

By Emma Peterson.  

How chemical testing helps verify formulations, troubleshoot performance issues and ensure regulatory compliance.  

In the roofing industry, we’ve all heard about mechanical performance tests. From ASTM’s impact rating to UL's fire classifications and beyond, there’s a lot of ways to see how a product will outwardly perform in the field. But testing the mechanics is just half of the story of a product. The other half is in its chemical formation. And that’s where groups like ACE Laboratories come into the picture.  

ACE is known for testing the formation of roofing products. This is incredibly helpful for organizations like the Cool Roof Rating Council (CRRC) that need to look at components like UV stabilizers that are chemically added to products to see how they relate to energy efficiency. But how exactly does one go about testing the chemical makeup of a roofing product? Erick Sharp, the CEO of ACE Labs, joined us for an episode of Roofing Road Trips® to explain.  

In general, there are three main tests that Erick’s analytical lab team performs regularly:  

• Thermogravimetric Analysis (TGA): For this test, scientists place a small amount of material on a scale that is built into an oven. From there they turn on the temp and start taking weights at different temperatures. Erick explained what this tells them, sharing, “As it’s baking you get a weighted quantitation of everything as it leaves. And taking those measurements you can get a quantitative breakdown of how much of each polymer or element is in the product at any given time.” 
• ICP-OES: The goal of this test is to identify all the elemental and organic ingredients in a formula. Knowing this informs the ACE team of "what type of fillers are being used in something, and, if there are aggregates in it, what kind of aggregates are in there based upon composition.” 
• Gas Chromatography – Mass Spectrometry (GC-MS): This does a similar thing as the ICP test, but instead of looking for organics, it focuses on inorganics or chemical additives. Erick highlighted this test for its importance in relation to anti-degradants, explaining, “Chemical additives are going into these products to help them resist UV sunlight, things like that. And so when there's a product failure, one of the things that comes up for outdoor applications all the time is, ‘Were you able to determine if there was actually anti-degradants in the compound? Was it formulated correctly? Was the ingredients actually put into the material?’”  

And if all three of these tests are performed on a product, you pretty much know everything you could ever need to know about the formula. As Erick put it, “With these three tests, we kind of have the whole circle of things. We know what performs and we also know the composition of it – we basically have a thumbprint of this product and can identify it based on that.”   

Why is understanding this on a chemical level so important? Many areas have regulations (like California Prop 65) about what can be in formulas. Having third-party labs like ACE verify what’s in a product can help manufacturers meet those requirements. The other big reason to conduct chemical testing is product development. Erick explained, “A fair number of people send product in because there was a change in performance or quality and they need to know what happened and why.” 

Want to learn more about chemical testing of roof products? Listen to the whole conversation with Erick!