Class A Metal Roof Assembly

The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.

Class a metal roof assembly. 0 0416 kg m 2 copper sheets installed over combustible decks. Class 1 roof covers. Class a roof assemblies include minimum 16 ounce per square foot copper sheets installed over combustible decks. Roofing assembly classification will need to be for each roofing project.

Aluminum panels surfacing identified as tee cee lock zee lock zee lock double lock and tee lock. A roof assembly must pass all these tests in order to gain a class 1 designation. A common misconception about roofs fire ratings is that building codes require class a. The other option in densdeck that is a gypsum panel that gets the roof assembly the class a rating.

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. Building code fire resistance requirements. A roofing membrane that is classified as part of a class a assembly when installed over a particular insulation may not qualify as part. Class a roof assemblies include minimum 16 oz sq.

Unfortunately the icc report indicates it requires a vent roof assembly. For example shake roofing with a fire retardant treatment rates class b on its own but achieves a class a rating when combined with specified underlying materials such as type 72 roll roofing material. Class a roof assemblies also include ferrous or copper shingles or sheets metal sheets and shingles clay or concrete roof tile or slate installed on noncombustible decks or ferrous copper or metal sheets installed without a roof deck on noncombustible framing. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.

Gaf versasheild is a fiberglass underlayment that gets an assembly a class a rating. To get the class a rating on a metal roof you need a listed assembly. Coated steel panels surfacing identified as deep vee r tee high seam tee zee lock zee lock double lock cee lock tee lock bermuda roof m s tile s spanish tile deep deck and double rib and tee lock panel. For insulated steel roof deck assemblies fm class 1 includes fm 4470 and fm 4450 approval standard for class 1 insulated steel decks roofs.

It should be noted that these classifications apply to roofing assemblies and not the roofing membrane. Assembly rated class a roof coverings are those that meet class a standards when combined with other elements.