Withstand a burning brand measuring 1 5 x 1 5 and weighing 1 4 gram.
Fire retardant roof covering class c.
Certain roof system types can be consid ered class a without testing based on their.
E108 defines the following conditions.
A fire resistant rating e g a class a class b or class c fire resistant rating.
The flame spread categories are as follows per astm e 84 ul 723.
And class c designates resistance to relatively light fire test exposure.
Burning a brand on a roof deck.
Building codes establish fire resistance requirements for roofs based on the type of construction e g concrete steel wood for the building.
Tested roof systems are fire classified class a b or c where the most fire resistant roof assemblies are class a and class c is least resistant.
Pressure treated shakes and shingles are the most common roofing materials to fall under the class b rating.
Class a or i.
Flame through to the underside of a roof deck.
Astm e108 defines fire test methods for roof coverings.
These tests may be conducted at ul inc fm global or any other certified testing laboratory.
Flame spread 25 or less frtw some fr surface coatings class b or ii.
A standard fire test is used to determine the fire rating of a roof covering.
Installa tion instructions will include use of an additional material under the aluminum covering in order to receive the class a by assembly rating.
Because of its low melting point it must be tested.
If wood shakes and shingles are impregnated with fire retardant chemicals they meet the requirements for a class b fire rating and can meet a class a rating if additional materials are included in the roof assemblies.
Building code fire resistance requirements.
Under such exposures roof coverings of this class are not readily flammable afford a measurable degree of fire protection to the roof deck do not slip from position and pose no flying brand hazard.
Class a designates resistance to relatively severe fire test exposure.
Class b designates resistance to relatively moderate fire test exposure.
The class c brand is about the size of an ice cube.
Class a b and c designations.
Roofing with a class c rating is able to.
Class c roofing provides only light fire protection.
Experience maximum flame spread of 13 feet.
Square sticks nailed together with sticks in the middle later running perpendicular to the outside layers.
A and b brands consist of a three layer sandwich construction of 3 4 in.
A common misconception about roofs fire ratings is that building codes require class a.
Wood shake plywood or particle board roof are the most common roofing types listed as class c.
Class c fire retardant treatment a product that is effective against light fire exposures.
Flame spread 76 to 200 untreated lumber and plywood frtw must have a flame spread of 25 or less in the 10 minute astm e 84 ul 723 test.
Each requires a spread of flame test and a burning brand test.
Flame spread 26 to 75 other fr surface coatings class c or iii.
An exception to this general rule is an aluminum covering.
