ASTM E84 - Flame Spread and Smoke Development in Roofing
As a follow-up to our August 2020 SpecTopics post, UL Fire Classifications for Roofs – Class A, B, and C, this post will touch on ASTM E84 and its relationship to roofing materials.
ASTM E84 Standard Test Method for Surface Burning Characteristics of Building Materials was specifically designed for testing interior building products or products that are exposed directly to the interior (wall coverings, carpet, drywall, etc.) These products could be directly exposed to a fire, if one occurs inside the building. Therefore, the test is designed to show how much additional fuel the product contributes to a fire (flame spread) or how much smoke it could produce, which would obstruct the occupants' ability to find exits or cause smoke inhalation issues (smoke development).
Roofing products have their own burn test, ASTM E108 Standard Test Methods for Fire Tests of Roof Coverings, which also gives roofs a classification of letter A, B, or C as explained in Chapter 15 of the International Building Code. This test sets up a certain amount of fuel (a prescribed amount of wood) on top of the roof assembly and sets it on fire in a controlled burn. This "burning brand" test is testing the surface burn characteristics of a roof assembly, as well as burning embers or flying debris landing on a roof from an adjacent property or from the same building. This test is the most likely scenario of an ignition source for a roof fire – an exterior source.
Roofing assemblies are also tested in assemblies by UL and receive interior fire ratings for use when referencing the table in the building code for fire resistance ratings of building elements (Chapter 6 of the international Building Code). These range from 0 to 1-1/2-hour assemblies for Type I through Type V construction.
The only reference to ASTM E84 testing in Chapter 15 (Roofing) of the International Building Code is for mechanical equipment screens directly on the roof. This is because past codes allowed building owners to use a range of materials which may or may not have been appropriate for fire resistance, such as untreated wood, fabric, or plastic. The current codes (2018 and 2021 editions of IBC) state that when using a mechanical screen, it must meet a flame spread index of 25 or less. This is to ensure designers and building owners are using metal or some other non-combustible material for rooftop-mounted equipment screens.
Roofing membrane manufacturers will not have testing information for their membranes for ASTM E84, but will have information on UL Class A, B, and C roofs as well as UL assembly numbers for interior fire ratings.
For more information on these tests, refer to the Code Approval Guides for each membrane type on Carlisle SynTec Systems' website.
EPDM Code Approval Guide
TPO Code Approval Guide
PVC Code Approval Guide
Please contact Craig Tyler with questions.
ASTM E84 Standard Test Method for Surface Burning Characteristics of Building Materials was specifically designed for testing interior building products or products that are exposed directly to the interior (wall coverings, carpet, drywall, etc.) These products could be directly exposed to a fire, if one occurs inside the building. Therefore, the test is designed to show how much additional fuel the product contributes to a fire (flame spread) or how much smoke it could produce, which would obstruct the occupants' ability to find exits or cause smoke inhalation issues (smoke development).
Roofing products have their own burn test, ASTM E108 Standard Test Methods for Fire Tests of Roof Coverings, which also gives roofs a classification of letter A, B, or C as explained in Chapter 15 of the International Building Code. This test sets up a certain amount of fuel (a prescribed amount of wood) on top of the roof assembly and sets it on fire in a controlled burn. This "burning brand" test is testing the surface burn characteristics of a roof assembly, as well as burning embers or flying debris landing on a roof from an adjacent property or from the same building. This test is the most likely scenario of an ignition source for a roof fire – an exterior source.
Roofing assemblies are also tested in assemblies by UL and receive interior fire ratings for use when referencing the table in the building code for fire resistance ratings of building elements (Chapter 6 of the international Building Code). These range from 0 to 1-1/2-hour assemblies for Type I through Type V construction.
The only reference to ASTM E84 testing in Chapter 15 (Roofing) of the International Building Code is for mechanical equipment screens directly on the roof. This is because past codes allowed building owners to use a range of materials which may or may not have been appropriate for fire resistance, such as untreated wood, fabric, or plastic. The current codes (2018 and 2021 editions of IBC) state that when using a mechanical screen, it must meet a flame spread index of 25 or less. This is to ensure designers and building owners are using metal or some other non-combustible material for rooftop-mounted equipment screens.
Roofing membrane manufacturers will not have testing information for their membranes for ASTM E84, but will have information on UL Class A, B, and C roofs as well as UL assembly numbers for interior fire ratings.
For more information on these tests, refer to the Code Approval Guides for each membrane type on Carlisle SynTec Systems' website.
EPDM Code Approval Guide
TPO Code Approval Guide
PVC Code Approval Guide
Please contact Craig Tyler with questions.
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