A Quick Guide to Roof Fire Ratings

Roofs are classified into four different fire ratings depending on their material. For you and your home’s safety, it’s best to learn more about your roof’s fire rating. Here, we walk you through the different classifications of roof fire ratings. 

Fire rating refers to your roof’s resistance to fire. The four ratings are Class A, B, C and unrated. Your roofing system is required to comply with building codes and insurance requirements. The following are the four fire ratings and how are they different from each other:

Class A Roofing

Class A roofing is the highest rating. Class A roofs are made of materials that are highly effective against severe fire exposure. It’s the most preferred choice for homeowners, especially when they live in an area that is prone to wildfires. Roofing materials like clay, concrete and sand-cast tiles are considered Class A rating. These materials resist fire penetration to the underlayment of the roof and the attic. Class A roof rating can last from two to four hours before ignition. 

Class B Roofing

Meanwhile, Class B roofing resists moderate fire exposures. This rating refers to the second-highest materials that are resistant to fire. Pressure-treated shakes and shingles that contain fire retardant chemicals are classified as Class B roofs. Class B materials in roofing usually last one hour before ignition. 

Class C Roofing

Class C is the rating for second-lowest resistance to fire. Class C materials only provide light fire protection. Untreated wood shakes and organic shingles are materials that are classified in this rating. Class C materials can only last 20 minutes before ignition. This rating is not advised for roofing.

Unrated Roofing

Unrated roofing means the materials used have no fire resistance at all. This is the lowest rating for resistance to fire. This type of roofing should be avoided because it does not protect your home from fire. Usually, building codes do not accommodate unrated roofing material.

For your roofing services, trust Krech Exteriors. Call us now at (651) 688-6368, or fill out our contact form to book an appointment. We serve clients in Minneapolis.