Whose responsibility is it to locate control joints within a masonry structure? When is it appropriate to eliminate vertical control joints in structural masonry walls? Movement joints often are overlooked for their importance to the integrity of masonry structures, and many times are inadequately addressed in typical notes or specifications rather than physically identified on structural plans.
In August 2021, Sam Rubenzer, PE, SE, from FORSE Consulting, presented Movement Joints for Masonry – Structural Edition for SE University. Sam explored the role of masonry movement joints in structural masonry walls, as well as the movement properties of masonry materials and structural systems. He explained the purpose of joints and what to consider when locating them, as well as who is responsible for locating them according to the code.
Sam suggested several NCMA TEK guides that are useful for engineers who need further guidance for designing movement joints in structural masonry walls. All of these guides are available for FREE download from NCMA and the links are included here for your reference.
- NCMA TEK Guide 10-1A Crack Control in Concrete Masonry Walls addresses various causes of cracking and crack control strategies.
- NCMA TEK Guide 10-2D Control Joints for Concrete Masonry Walls – Empirical Method provides guidance for typical masonry buildings using a more empirical approach to locating movement joints.
- NCMA TEK Guide 10-3 Control Joints for Concrete Masonry Walls – Alternative Engineered Method explores a more engineered approach to movement joints and horizontal reinforcement.
- NCMA TEK Guide 10-4 Crack Control for Concrete Brick and Other Concrete Masonry Veneers applies to cracks resulting only from internal volume change of the concrete masonry veneer and does not address cracking due to externally applied loads.
Additionally, Sam referenced The Masonry Society’s TMS 402/602-16 Building Code Requirements and Specifications for Masonry Structures which is referenced by the International Building Code 2018 and is available to purchase through the above link. This document is essential when designing masonry structures and, as Sam noted, makes clear the responsibility lies with the designer to “indicate type and location of movement joints on the project drawings.”
Properly designed movement joints and horizontal reinforcement are critical for successful, crack-free masonry structures. These resources can be used for simple, straightforward designs or to explore additional options for the design of movement joints when an empirical approach falls short on your next masonry project.