Pvc Roofing Fire Rating

If the type of insulation in the structure is more flammable such as polymeric insulations it can affect the amount of slope that the roof can have to achieve a class a rating.

Pvc roofing fire rating. Pvc roofing membranes have a solid fire resistance rating. The slope of the test specimen is preselected and since steeper slopes are more of a challenge due to melting material feeding the fire the rating applies to the maximum slope passed. Our preference at royalty roofing is pvc single ply roofing systems but we can install any type of roof that our customers require. Ib roof system s products are specifically engineered for strength and our pvc roofing membranes far surpass the minimum astm standard 200 lbf in.

Fire ratings for roofs are classified as either class a class b class c or are unrated if a roof covering cannot meet the requirements for any of these classifications. These roofs are difficult to ignite burn slowly do not support combustion and self extinguish when the source of flame is removed. Not all buildings are required to have a class a fire rating for their roofs. The maximum flame spread is 6 feet for a class a rated roof 8 feet for class b and 13 feet for class c.

But if it is required all the above factors are evaluated to give the structure its rating. Figure 9 2 total dioxin formation 0 01 source. Read the full fire resistant roofing report. Pvc roofing membranes have passed fm and ul fire testing and have an unlimited slope approval.

Ul and fm ratings are specific to individual roofing membrane manufacturers. The building is an excellent example of a fire breaking out on a flat roof adjacent to other buildings and illustrates well the need to consider the external fire ratings of flat roofs both to protect the inhabitants the penetration of the fire element of the buildings but also the people and property nearby more associated with the spread. Comparing ul class a fire ratings with isocyanurate insulation as the substrate the tpo membrane has a maximum slope of 0 5 inch in 12 the pvc is at a 2 in 12 and the epdm achieves a class a at a 0 5 inch in 12 for unreinforced adhered membranes and 0 75 inch in 12 for reinforced mechanically attached membranes. Not all pvc is built like ib pvc.

Pvc and fire figure 9 1 estimated relative contribution to total tcdd released into the atmosphere from combustion sources. Pvc roofs have passed applicable factory mutual fm and underwriters laboratories ul tests for class a and b roof assemblies for high and low slope roof applications. Class a is the highest rating offering the highest resistance to fire and unrated is the worst.