Galvanized Sheet Metal Fire Rating

Occasionally the american galvanizers association gets the question of whether the galvanized coating is adversely affected by exposure to fire.

Galvanized sheet metal fire rating.

When there is no insulation used on top of the corrugated steel sheet the heat goes through the metal and dissipates upwards and the. Fire ratings are based on an assembly. Sheet metal penetrations are used in rated assemblies and when correctly fire caulked. The mbma fire tests of exterior walls in 1997 resulted in a new uldesign no.

Specifications methods to determine fire resistance ratings for generic designs can be found in most building codes e g chapter 7 fire resistance rated construction international building code international code council falls church va 2003. One sheet of 5 8 type x sheetrock has no fire rating. But when it is used one on each side of a properly framed wall it can become a fire rated wall. The nonfire side of a fire rated assembly exceeds 325 degrees above its ambient temperature.

W404 1 hour rated fire wall and w413 2hour rated fire wall. I am not aware of a fire rated wall assembly using sheet metal. If combined with gypsum or other materials in an assembly it. Both designs allow for new and retrofit metal building use and provide the flexibility to meet future energy code requirements for higher insulation levels.

V421 which pro vides 1 and 2 hour fire resistance ratings for exteri or walls in metal buildings. A galvanized sheet by itself would not have a fire rating. The most common fire rating material used in metal buildings is gypsum wallboard. There is a potential for coating damage but many have found fire damage to minimal on galvanized steel.

A specific field erected construction of an assemblage of materials designed to prevent the spread of fire through openings. The thickness and number of the layers of type x gypsum wallboard are specified for each. The steel sheet bends but the load bearing capability remains for a significant amount of time. Temperatures in fires can easily exceed 1 000 f.

The ratings are for unsymmetrical walls that require ratings from both sides. The sheet metal and air. Box 739 kennedale tx 76060 physical address 528 s. Kennedale tx 76060 phone 817 478 0801 fax 817 483 6571 page 6 of 43 sheet metal standards duct guage and enforcing for 1 ess drive heavy ga metal gauge of metal duct dimensions 5 joint 4 joint 2 5 joint 2 joint.

Chapter 8 fire resistive materials and construction nfpa 5000 building construction and safety code nfpa quincy ma 2006. Fire ratings are generally based upon testing of a structural sample.