scope:

This standard applies to any component intended for use in a cavity wall system.

Cavity wall systems are exterior wall constructions typically consisting of two walls separated by a cavity which contains an air gap. For cavity wall systems, the exterior facade can be made of brick or masonry construction, insulated or non-insulated panels, or ventilated siding. The interior can be made of combustible or noncombustible construction materials. Systems installed with ventilated siding, including metal faced panels (i.e. Aluminum Composite Material (ACM) or Metal Composite Material (MCM)), are often referred to as rainscreen systems. The cavity can contain insulation and other components which can be used to minimize heat loss in colder climates and solar gain in warmer climates. Insulation can be supplied in many forms including, but not limited to, rigid board stock and spray foam. Other components such as air and moisture retarders or weather resistive barriers (WRBs) may also be present.

Cavity wall systems that are tested in accordance with this standard must have an air gap. Systems without an air gap shall be tested to FM Approvals Examination Standard 4880, Class 1 Fire Rating of Insulated Wall or Wall and Roof/Ceiling Panels, Interior Finish Materials or Coatings and Exterior Wall Systems, ANSI FM 4880, American National Standard for Evaluating Insulated Wall or Wall and Roof/Ceiling Assemblies, Plastic Interior Finish Materials, Plastic Exterior Building Panels, Wall/Ceiling Coating Systems, Interior or Exterior Finish Systems, FM Approval Standard 4881, Class 1 Exterior Wall Systems, or ANSI FM 4881, American National Standard for Evaluating Exterior Wall Systems, as applicable.

Systems that are tested in accordance with this standard must have adequate fire resistance on the interior side. Constructions without adequate fire resistance shall meet the requirements of FM Approvals Examination Standard 4881, Class 1 Exterior Wall Systems.

This standard does not grant certification for cavity wall systems as hourly rated fire barriers.

This standard shall not qualify exterior insulated finish systems (EIFS) or other exterior wall coating systems.

This standard is limited to constructions with 1 - 4 in. (25 - 102 mm) wide air gaps.

Purpose

This standard states testing and certification requirements for cavity wall systems. The primary use of cavity walls is to allow moisture that has penetrated the exterior surface to drain down the cavity space to flashing that directs the water to weep holes that allow the water to drain from the cavity.

Testing and certification criteria includes, but may not be limited to, performance requirements, marking requirements, examination of manufacturing facility(ies), audit of quality assurance procedures, and a surveillance program.