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Fire Resistance Ratings of Concrete Masonry Assemblies

CMHA TEK 07-01D

Concrete masonry is widely specified for fire walls and fire barriers because concrete masonry is noncombustible, provides durable fire resistance, and is economical to construct. Chapter 7 of the International Building Code (IBC) (ref. 2) governs materials and assemblies used for structural fire resistance and fire-rated separation of adjacent spaces. This TEK is based on the provisions of Code Requirements for Determining Fire Resistance of Concrete and Masonry Construction Assemblies, ACI 216.1/TMS 216 (ref. 1) , which outlines a procedure to calculate the fire resistance ratings of concrete masonry assemblies. The 2014 edition of the ACI 216.1/TMS 216 is referenced in the 2015 IBC for concrete and masonry materials. This TEK is based on both prescriptive details and tables as well as the calculated fire resistance procedure, which is practical, versatile and economical. The calculation procedure allows the designer virtually unlimited flexibility to incorporate the excellent fire-resistive properties of concrete masonry into a design. Included are methods for determining the fire resistance rating of concrete masonry walls, columns, lintels, beams, and concrete masonry fire protection for steel columns. Also included are assemblies composed of concrete masonry and other components, including plaster and gypsum wallboard finishes, and multi-wythe masonry components including clay or shale masonry units.

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Crack Control Strategies for Concrete Masonry Construction
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This TEK covers acoustic requirements for concrete masonry highway sound barriers. For structural design considerations, the reader is referred to Allowable Stress Design of Pier and Panel Highway Sound Barrier Walls (refs. 3).
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Noise Control with Concrete Masonry
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Sound Transmission Class Ratings for Concrete Masonry Walls
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Concrete Masonry Unit Shapes, Sizes, Properties, and Specifications
The most widely used standards for specifying concrete masonry units in the United States are published by ASTM International. These ASTM standards contain minimum material and property requirements that assure quality performance. These requirements include items such permitted constituent materials, minimum compressive strength, maximum linear drying shrinkage, maximum absorption, permissible variations in dimensions, and finish and appearance criteria.The letter and first number of an ASTM designation is the fixed designation for that standard. For example, ASTM C90 (REF. 1) is the fixed designation for loadbearing concrete masonry units. The number immediately following indicates the year of last revision (i.e., ASTM C90-16 would be the version of C90 published in 2016). Because significant changes can be introduced into subsequent editions of standards, the edition referenced by the building code or by a project specification is an important consideration when determining specific product requirements. For the discussion presented here, the ASTM requirements reviewed have remained relatively static unless otherwise noted.
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Joint Sealants for Concrete Masonry Walls
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Flashing Details for Concrete Masonry Walls
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