Building codes require metal building construction to be fire rated in certain situations. To address these requirements, MBMA conducted fire tests at UL (Underwriters Laboratory), Intertek (Omega Point) and FM Global (Factory Mutual) that resulted in fire protection details that are UL listed. Details address roof/ceiling, wall, column, joint, and wall continuity systems.
The following table summarizes all the MBMA/UL tested fire-resistance rated assemblies and includes hyperlinks that will take you to UL's website, UL Product iQ. Access to UL Product iQ and its Fire-Resistance Ratings is free, but requires registration. (Please note these links will take you away from the www.mbma.com website).
|CONSTRUCTION TYPE||UL RATED ASSEMBLY||HOURS||DESCRIPTION|
|Column||Built-up I-shape||X524||1, 2||Gypsum Board|
|Light-gauge channel||X530||1, 2||Gypsum Board|
|P265||1, 1.5||Acoustical Tile|
|P268||1, 1.5||Acoustical Tile|
|Wall||Load Bearing||U425||0.75, 1, 1.5, 2||Gypsum Board|
|U489||1, 1.5, 2||Gypsum Board|
|Non-Load Bearing||U419||1, 2, 3, 4||Gypsum Board|
|V421||1, 2||Gypsum Board with girts at 48-in. max o.c. spacing|
|W404||1||Gypsum Board with girts at 90-in. max o.c. spacing and mineral wool, option for rigid foam board|
|W413||2||Gypsum Board with girts at 90-in. max o.c. spacing, option for rigid foam board|
|W447 / ULC U421||1, 2||Gypsum Board with girts at 48-in. max o.c. spacing|
|Joints, Compressed Insulation System||Purlin - Inside Wall||HW-D-0488||1||Gypsum Board and fire caulk with rated roof ceiling|
|Purlin - Perpendicular to Wall||HW-D-0489||1||Gypsum Board and fire caulk with rated roof ceiling|
|Purlin - Parallel to Wall||HW-D-0490||1||Gypsum Board and fire caulk with rated roof ceiling|
|Joints, Cavity Filled Insulation System||Purlin - Inside Wall||HW-D-0926||1||Gypsum Board and fire caulk with rated roof ceiling|
|Purlin - Perpendicular to Wall||HW-D-0927||1||Gypsum Board and fire caulk with rated roof ceiling|
|Purlin - Parallel to Wall||HW-D-0928||1||Gypsum Board and fire caulk with rated roof ceiling|
|Wall Continuity-Joint, Compressed Insulation System||Purlin - Inside Wall||CJ-D-0005||1||Gypsum Board and fire caulk with non-rated roof|
|Purlin - Perpendicular to Wall||CJ-D-0006||1||Gypsum Board and fire caulk with non-rated roof|
|Purlin - Parallel to Wall||CJ-D-0007||1||Gypsum Board and fire caulk with non-rated roof|
Wall Continuity-Joint, Cavity Filled Insulation System
|Purlin - Inside Wall||CJ-D-0029||1||Gypsum board and fire caulk with non-rated roof|
|Purlin - Perpendicular to Wall||CJ-D-0030||1||Gypsum board and fire caulk with non-rated roof|
|Purlin - Parallel to Wall||CJ-D-0031||1||Gypsum board and fire caulk with non-rated roof|
The fire protection assemblies for metal building frames have historically been gypsum board enclosures, such as those listed in the above table, including UL Design No. X524. However, an MBMA study determined that it is also feasible to use other common materials such as spray-applied fire resistive materials (SFRM) or intumescent coatings. More information about these alternatives is available.
MBMA also published the Fire Resistance Design Guide for Metal Building Systems. This guide contains the most complete and up-to-date information on the subject of fire resistance for metal building systems. For more information about this guide, please click here.