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  • Feature Story

Stronger Together: Increase Confidence with Certified Composite Products

July 23, 2018

Dwayne Sloan – UL LLC

Many model codes, municipal laws and regulations require building materials, such as insulation materials, to be tested and evaluated in accordance with UL 723 or ASTM E84, Surface Burning Characteristics of Building Materials, before they can be installed in a jurisdiction. UL 723 and ASTM E84 provide the flame spread and smoke developed index values for these building materials. This test method can provide data on composite materials, such as batt and blanket insulation products comprised of fiberglass insulation, adhesives and facings.

However, this method is also capable of providing test results on the individual components of a composite product, such as the individual fiberglass insulation, adhesives and facings. One misconception is that the individual component values can be used to represent the composite material for compliance with UL 723 or ASTM E84 regulation or specifications.

It is important to understand that products, such as batt and blanket insulation, are tested as a composite material. Experience and historical data has shown that as a rule, component values cannot be considered as worse case or additive to represent the composite product. In other words, three components with a flame spread of 5 will typically not yield a flame spread of 5 for the composite.

Similarly, three components with a flame spread of 5 have not been shown to reliably predict a flame spread of 15 for the composite. Only testing the composite product will demonstrate the actual values. The requirement to test composite materials is reflected in UL 723, ASTM E84, as well as ASTM E2988 Flexible Fibrous Glass Insulation for Metal Buildings.

While codes may not always require third-party certification, there are numerous benefits to looking for third-party certification and labeling of the final, composite products.

Third-party certification demonstrates an ongoing commitment to safety and quality. For some specific products, such as faced blanket insulation, third-party certification can also prove beneficial because it demonstrates that the composite material – the insulation, adhesive and facing – has been evaluated and certified rather than the individual components.

This is an important distinction because combining materials can change the overall behavior of the final composite. This means that, even if the insulation itself were certified, the addition of adhesive and facing may change the behavior of the composite when exposed to fire.

It is another common misunderstanding that if one of a manufacturer’s materials is certified, their other materials are, as well. This is not always the case as certifications are issued by product. Most importantly, this means that if an unfaced insulation is certified and facing is added by the manufacturer or another party after the certification is complete, the final faced-form of the insulation does not bear certification. Often, the easiest way to avoid this issue is to look for finished materials with a reliable third-party certification.

Certification with UL means a product has been evaluated, complies with UL’s requirements, and is manufactured under a Follow-Up system, meaning the certification extends beyond testing. This Follow-Up Program allows UL to verify that products remain compliant with requirements and are produced in a manner representative of the construction of the product that was originally evaluated and certified. UL's Classification Mark on insulation products – "UL Classified" is the applicable term – is the manufacturer's representation that samples of that product have been evaluated as to their surface burning characteristics in accordance with UL 723 (ASTM E84).

The many advantages of third-party certification lead some building material product manufacturers to make it company policy to obtain UL Classification for their products to minimize the possibility of non-acceptance by Authorities Having Jurisdiction. Additionally, many purchasers, building designers and building owners understand UL certified materials are reliable. Specifying UL-Classified building materials also means the materials will automatically come with third-party quality control which, in turn, means UL will establish a field report to determine the nature of the nonconformance and take appropriate corrective action should an issue occur.

Composite products bearing the UL Mark demonstrate commitment to meeting model codes, municipal laws and regulations. You can verify a certification by checking UL’s Product iQ database. Why take a risk when you don’t have to?