1406 Metal Composite Material (mcm) — 2025 California Building Code

The provisions of this section shall govern the materials, construction and quality of metal composite material (MCM) for use as exterior wall coverings in addition to other applicable requirements of Chapters 14 and 16.

MCM used as exterior wall covering or as elements of balconies and similar projections and bay and oriel windows to provide cladding or weather resistance shall comply with Sections 1406.4 through 1406.13.

MCM used as architectural trim or embellishments shall comply with Sections 1406.7 through 1406.13.

[BS] 1406.4 Structural design. MCM systems shall be designed and constructed to resist wind loads as required by Chapter 16 for components and cladding.

Results of approved tests or an engineering analysis shall be submitted to the building official to verify compliance with the requirements of Chapter 16 for wind loads.

MCM systems shall comply with Section 1402 and shall be designed and constructed to resist wind and rain in accordance with this section and the manufacturer’s installation instructions.

MCM systems shall be constructed of approved materials that maintain the performance characteristics required in Section 1406 for the duration of use.

Where MCM systems are used on exterior walls required to have a fire-resistance rating in accordance with Section 705, evidence shall be submitted to the building official that the required fire-resistance rating is maintained.

Exception: MCM systems that are part of an exterior wall assembly not containing foam plastic insulation and are installed on the outer surface of a fire-resistance-rated exterior wall in a manner such that the attachments do not penetrate through the entire exterior wall assembly, shall not be required to comply with this section.

EXTERIOR WALLS

Unless otherwise specified, MCM shall have a flame spread index of 75 or less and a smokedeveloped index of 450 or less when tested in the maximum thickness intended for use in accordance with ASTM E84 or UL 723.

Where installed on buildings of Types I, II, III and IV construction, metal composite material (MCM) shall comply with Sections 1406.10.1 and 1406.10.2 for installations up to 40 feet (12 192 mm) above grade plane. Where installed on buildings of Type I, II, III and IV construction, MCMs and MCM systems shall comply with Sections 1406.10.1 through 1406.10.3, for installations greater than 40 feet (12 192 mm) above grade plane.

1406.10.1 Surface-burning characteristics. MCM shall have a flame spread index of not more than 25 and a smoke-developed index of not more than 450 when tested in the maximum thickness intended for use in accordance with ASTM E84 or UL 723.

1406.10.2 Thermal barriers. MCM shall be separated from the interior of a building by an approved thermal barrier consisting of 1 / 2 -inch (12.7 mm) gypsum wallboard or material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275.

Exceptions:

1. The MCM system is specifically approved based on tests conducted in accordance with NFPA 286 and with the acceptance criteria of Section 803.1.1.1, UL 1040 or UL 1715. Such testing shall be performed with the MCM in the maximum thickness intended for use. The MCM system shall include seams, joints and other typical details used in the installation and shall be tested in the manner intended for use.

2. The MCM is used as elements of balconies and similar projections, architectural trim or embellishments.

1406.10.3 Full-scale tests. The MCM system shall be tested in accordance with, and comply with, the acceptance criteria of NFPA 285. Such testing shall be performed on the MCM system with the MCM in the maximum thickness intended for use.

MCM shall be permitted to be installed on buildings of Type V construction.

Where MCM systems are included in an exterior wall assembly containing foam plastic insulation, the exterior wall assembly shall also comply with the requirements of Section 2603.

MCM shall be labeled in accordance with Section 1703.5.