License #CCC1331246

Roof Fire Rating Guide

In the event of a fire, it is vital that your roof does not collapse. Likewise, if your neighbor’s house catches on fire, then you do not want embers from his roof blowing over to catch your property on fire. Choosing a roof with a high fire rating may also entitle you to a discount on your homeowners insurance. Florida Building Code also sets minimum requirements that homeowners must meet across the state.

Where are Roofing Material Fire Tests Conducted?

All manufacturers of roofing materials must submit their products to be fire tested by certified laboratories. The two largest labs to test these materials are the Underwriters Laboratory and FM Global. Regardless of where the materials are tested, the testers must be independent of the company producing the roofing materials. Furthermore, the classification system is designed by the American Society for Testing and Materials. The exact rule that applies is ASTM E108.

How are Fire Ratings for Roofing Materials Determined?

There are a variety of test performed to see if the roofing materials will catch on fire easily. Each material is given a rating from A to C or unrated. A is the least flammable roofing material that you can buy.

What are the Standards for Non-combustible Roof Decks?

Non-combustible roof decks, like steel, poured gypsum, or concrete, then only the spread of the flame is measured. In order to receive a class A rating, the spread must be less than 6 feet while the spread must be less than 8 feet to get a class B rating. In order to be rated a class C, the spread must be less than 13 feet. If the spread is more than 13 feet, then the test is left as unrated.

What are the Standards for Combustible Roof Decks?

If the roof deck is combustible, then it must pass two additional tests. The first of these is the ignited brand test. During this test, a lighted wood lattice is laid directly on the roofing material. When the decking catches on fire, the test is ended. A 9.25-gram is used during the class C part of the test while a 500-gram lattice is used during the class B portion. Finally, a 2,000-gram lattice is used during the class A portion.

Additionally, an intermittent test is performed using a gas flame that is cycled on and off. In order to get a class C rating, the roof must not ignite when the flame is cycled three times while if it can withstand five more cycles, then it is given a class B rating. In order to earn a class A rating, the materials must be able to endure 15 cycles without igniting.

There are lots of different factors that go into determining the safety of your roof. Talk to JV Contractors, LLC to learn more about these factors before making a final decision about the roof that meets your needs the best.