Roof Covering Classes

Contrary to what many think there are no class a roofing membranes.

Roof covering classes.

Roof systems are segregated into combustible and non combustible construction types. Commercial roofing 101 is a free 2 hour demonstrative class focusing on the principles of roofing and the relationship to property management. To meet class a the test specimen must resist 15 cycles class b eight cycles and class c three cycles. The operative word here is systems.

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 is considered to be the classiest type of roof cover. 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. The intermittent flame test.

Slate roofing is the perfect topping to an elegant home providing amazing textures and style. Class a provides the best fire resistance and therefore the best protection for your home. The preeminence of ul is most likely due to their ansi ul 790 protocol. An example of an unrated covering is an untreated wood shake roof.

The irc addresses roof covering requirements in several areas. Under ul 790 roof systems are evaluated for external fire. Common stand alone class a roof coverings include clay tiles slate asphalt glass fiber composition shingles and concrete tiles. A class 4 roof covering receives the highest premium credit.

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. The astm e 108 ul 790 roof coverings test does not produce a flame spread rating. 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.

The class a brand weighs 2 000 grams class b 500 grams and class c 9 1 4 grams. Roof coverings that have passed the ul standard 2218 test are classified as either class 1 2 3 or 4. Class a is the highest rating offering the highest resistance to fire and unrated is the worst. The list of approved laboratories is shown below.

It is very high quality and very low maintenance with a life expectancy of hundreds of years. As you contact various contractors or suppliers you should ask about roofing materials that meet ul standard 2218. Assembly rated class a roof coverings are those that meet class a standards when combined with other elements. A gas flame is cycled on and off.

It comes in various grades and colors. Failure is defined as the point where the roof deck ignites.