According to the scope of fm 4470.
Fm class 1 roof assembly.
Designed to help roofing professionals roofnav provides easy access to the most up to date fm approved roofing related information and related installation.
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.
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.
For insulated steel roof deck assemblies fm class 1 includes fm 4470 and fm 4450 approval standard for class 1 insulated steel decks roofs.
The panel roof assembly meeting the requirements of this standard shall receive a listing in roofnav as a class 1 x y panel roof.
According to the scope of fm 4470.
The performance of a panel roof depends in part on all components in its makeup and on how these components interact.
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.
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.
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.
Versiflex pvc mechanically attached roofing system factory mutual fm approvals b.
To be rated as a class 1 panel roof assembly only class 1 approved components may be used.
This standard applies to any component intended for use in assembling a panel roof including metal and plastic panel roofs.
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.
As wind flows over the building the pressure directly above the surface of the roof decreases.
Where x indicates the hail damage resistance mh or sh and y indicates the windstorm classification 60 75 90 105 120.
Would require an fm approved class 1 60 system design and follow the requirements of data sheet 1 29.
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.
However the absence of a hail damage resistance indicates sh.
