A roof can acquire a fire rating of either Class A, Class B, Class C, or unrated. A Class A roof is ideal for fire protection and—depending on the place of residence—often required by the building codes. Whether you are building a new home or planning an addition, it is important to understand each classification when choosing materials for the roof installation.
Class A Roofing. A Class A roof is the preferred choice and particularly vital when the home is located in an area that is prone to wildfires. The roof must be able to last two to four hours before ignition, experience a maximum flame spread of six feet, and resist 15 cycles of a gas flame turned on and off in order to achieve a Class A rating. Slate, clay tiles, concrete tiles, and fiberglass shingles are common examples of stand-alone Class A roofing.
Class B Roofing. A Class B roof is proven to be effective against moderate fire exposures. To achieve this rating, the roof must be able to experience a maximum flame spread of eight feet, last an hour before ignition, and resist eight cycles of a gas flame turned on and off. Common roofing materials to fall into this category, according to a roof inspection specialist, include pressure-treated shakes and shingles.
Class C Roofing. This roof rating for roofs provides light protection against fires. A roof with a Class C rating must be able to experience a maximum flame spread of 13 feet, last 20 minutes before ignition, and resist three cycles of a gas flame turned on and off. Examples of Class C roof coverings are unrated wood shakes and shingles, particleboard, and plywood.
Unrated Roofing. An unrated did not meet the requirements for any fire rating. It provides little to no protection and should not be used. In fact, most building codes will not accommodate any unrated roofing material.
For roof replacement and storm damage repair services, turn to DePalma Construction. Our certified roofers are committed to providing industry-leading products and outstanding customer service to ensure the comfort and satisfaction of each and every client. Call us at (717) 275-9589 or fill out our contact form to request a free, no-obligation estimate.