Roof Covering Classes

Common stand alone class a roof coverings include clay tiles slate asphalt glass fiber composition shingles and concrete tiles.

Roof covering classes.

Assembly rated class a roof coverings are those that meet class a standards when combined with other elements. The intermittent flame test. It comes in various grades and colors. A gas flame is cycled on and off.

Slate is considered to be the classiest type of roof cover. An example of an unrated covering is an untreated wood shake roof. Class a is the highest rating offering the highest resistance to fire and unrated is the worst. The irc addresses roof covering requirements in several areas.

Class a provides the best fire resistance and therefore the best protection for your home. Participants earn 2 0 cma continuing education credits. We recommend having a class a fire rated roof covering but you should understand its limitations particularly those related to edge of roof issues since standard roof tests do not evaluate potential vulnerabilities at these locations. Examples of a class a roof covering include concrete or clay roof tiles fiberglass asphalt composition shingles and metal roofs.

It is an entirely different test from astm e 84 ul 723 and it includes weathering per the astm d 2898 standard rain test. Slate roofing is the perfect topping to an elegant home providing amazing textures and style. The operative word here is systems. It is a pass fail test under which a product either passes the criteria as a class a b or c roof covering system or it doesn t.

Contrary to what many think there are no class a roofing membranes. The list of approved laboratories is shown below. Fire resistance is covered in section r902 and insulation is addressed in section r906 but the majority of the requirements are presented in section r903 and r904 which address weather protection and materials respectively. To meet class a the test specimen must resist 15 cycles class b eight cycles and class c three cycles.

Failure is defined as the point where the roof deck ignites. We will discuss the different roofing systems advantages materials and demographic concerns of roofs and common problems associated with roof failures and how to identify them. As you contact various contractors or suppliers you should ask about roofing materials that meet ul standard 2218. A class 4 roof covering receives the highest premium credit.

Roof coverings that have passed the ul standard 2218 test are classified as either class 1 2 3 or 4. Commercial roofing 101 is a free 2 hour demonstrative class focusing on the principles of roofing and the relationship to property management. Roof systems are segregated into combustible and non combustible construction types. The astm e 108 ul 790 roof coverings test does not produce a flame spread rating.

The class a brand weighs 2 000 grams class b 500 grams and class c 9 1 4 grams. The preeminence of ul is most likely due to their ansi ul 790 protocol.