One should ensure (via, e.g., ICC-ES Evaluation Service Reports) that the published loads for connectors are associated with the specified masonry design strength, f’m, being used. Thus, fastening to head joints should generally be avoided, even if the head joints are fully buttered. Note: CMU head joints are generally not a reliable substrate for anchoring due to non-uniform buttering between adjacent units and the stress discontinuities between the mortar and adjacent blocks. Possible installation locations include the face of the masonry wall (including bed joints, webs and the center of face shell), the top of the wall (directly into grout), and the sides of the wall.

Grout-filled CMU offers the highest load capacity of the three masonry types listed.

Three major categories to which components are fastened are explored in this article: In addition to cast-in tie wires, veneers and other elements are connected with a variety of embedded fasteners, including power-actuated pins (nails), screws and anchors. This article describes various types of fasteners for masonry, notes specific installation and application considerations, and emphasizes the value of third-party evaluation reports issued by, e.g., ICC Evaluation Service LLC (ICC-ES). Where reliable performance is desired, the most common assurance that masonry fasteners will satisfy the demands of masonry design is provided through certification by well-established third-party evaluation agencies. Renderings courtesy of the International Masonry Institute ( When attaching structural and non-structural components to masonry, understanding the embedded fastening options along with their advantages, limitations and challenges is the first step to a successful connection. Details for cladding anchorage to hollow CMU (top) and grouted CMU (bottom). April 2016 By Kenton McBride, Hilti North America Figure 1.

Hilti anchors in cmu block