Fm Class 1 Roof Assembly

Approval standard fm 4470single ply polymer modified bitumen sheet built up roof bur and liquid applied roof assemblies for use in class 1 and noncombustible roof deck construction approval standard fm 4471class 1 panel roofs approval standard fm 4475class 1 steep slope roof covers approval standard fm 4476flexible photovoltaic modules.

Fm class 1 roof assembly. For insulated steel roof deck assemblies fm class 1 includes fm 4470 and fm 4450 approval standard for class 1 insulated steel decks roofs. While a class 1 assembly can be substituted for a class a b or c roof assembly a class a b or c assembly cannot be substituted for a class 1 roof assembly. As wind flows over the building the pressure directly above the surface of the roof decreases. The performance of a panel roof depends in part on all components in its makeup and on how these components interact.

According to the scope of fm 4470. Where x indicates the hail damage resistance mh or sh and y indicates the windstorm classification 60 75 90 105 120. Fm class 1 roof deck construction and insulation approvals 1 membrane type. Roof damage caused by wind occurs when the air pressure below the roofing assembly is greater than the air pressure above the building s roof.

The panel roof assembly meeting the requirements of this standard shall receive a listing in roofnav as a class 1 x y panel roof. 050 060 or 080 versiflex pvc reinforced membrane white gray or tan deck type 2 insulation 3 insulation thickness maximum slope for astm e 108 class a rating. A class i insulated steel roof deck is one which meets the criteria of this standard for fire wind uplift live load resistances corrosion of metal parts and fatigue of plastic parts. Versiflex pvc mechanically attached roofing system factory mutual fm approvals b.

Take the guesswork out of an fm approved roof roofnav can take the guesswork out of configuring an fm approved roofing system leaving you to focus on what matters most. To be rated as a class 1 panel roof assembly only class 1 approved components may be used. The class 1 rating is an exclusive designation that can only be awarded by fm global which indicates the successful testing of the entire roof assembly using fm approval standard 4470. The class 1 rating is an exclusive designation that can only be awarded by fm global which indicates the successful testing of the entire roof assembly using fm approval standard 4470.

This standard applies to any component intended for use in assembling a panel roof including metal and plastic panel roofs. According to the scope of fm 4470. The standard applies to all components as assembled in the system below the roof cover.