FIND A CONTRACTOR BUYER'S GUIDE
BECOME AN INDUSTRY PARTNER
MCAA Logo
MEMBER LOGIN JOIN
NEWS
Join Us For The 75th Anniversary Midyear Meeting Sep 7-11 ↗

Vertical rebar positioners

Words: Mike Ripley/Public/News/20120519070000-1.jpg" width="600" height="338" border="0" alt="Vertical rebar positioners aid the mason contractor in centering the bars in the core of the block." />
Vertical rebar positioners aid the mason contractor in centering the bars in the core of the block.
Vertical rebar positioners have been part of the masonry accessory package for many years. They add no structural value to the wall, but aid the mason contractor in centering the bars in the core of the block and also help to simplify the lapping process.

The most popular and economical positioners for vertical applications are the Figure 8 or S type and the O ring. They are installed perpendicular to the plane of the block crossing the core with the wire loops centered. Positioners are set in the mortar of the bed joint for stability and vertical spacing is about every four feet.

Placement tolerances for single rebar applications are listed in Specification for Masonry Structures (TMS 602-08/ACI 530.1-08/ASCE 6-08) under Part 3 — Execution 3.4 B.8. Working from the center point of the core you are allowed + ½ inch in the width or thickness of the wall and 2 inches along the length of the wall. This leaves you a space in the core center of 1 inch wide by 4 inches long to be code compliant for vertical applications.

Some masons install bars manually (by sight) and others with the aid of positioners but all with the risk of not meeting code. While the use of rebar positioners greatly narrows the margin of error, they also move during installation due to sitting on top of the shelf of the CMU and moving when mortar or the next course is applied.

A new trend in vertical rebar positioners has emerged to solve the movement issue during installation. Core inserted positioners, which are designed to fit 1½-inch deep, cross the core diagonally and fit tightly in the corners of the core. The core positioners perfectly position the bars in the code compliance zone and allow no movement during installation. They also have an extended tail section (safety bend) so if installed incorrectly (out of plane), the tail will extend outside the wall alerting the mason to turn it in the opposite position.

Double vertical core positioners are also available but with a different design, spacing the loops or guides closer to the face shell of the CMU. To complete the family there is a bond beam positioner that positions bars in the lower one-third of the unit and ½-inch off the inside face shell.

Take the guesswork out of rebar placement by using the core inserted positioners.
 0
Chairman's Message: REFLECTIONS SPANNING SEVENTY-FIVE YEARS
September 2025

MCAA has been posting lots of wonderful old photos from decades of records as we celebrate our 75th Anniversary. Many of these photos are black and white and show people at our MCAA events with men wearing suits and ties while the women wore dressy gowns

Dick Dentinger
Chairman’s Message
Read More
Business Building: What Are You Doing To Develop Future Leaders?
September 2025

When I ask my coaching clients if they have anyone in their construction company who could potentially move up from field superintendent to estimator or project manager, the typical answer is “No!” The same answer is usually given when asked if they have

George Hedley
Business Building
Read More
Building More: Smoke Signals or Fire Extinguishers
September 2025

Ever watch a hot-potato game break out on your jobsite? It usually starts small. Somebody spots a crooked door frame, mutters, “I’ll make a note,” and flicks the issue to the next trade like it’s radioactive. By the time that frame comes back around, dryw

Corey Adams
Building More
Read More
MASONRY STRONG Podcast, Episode 27 Recap: Rob McKay, Chief Operating Officer at Instone
September 2025

On this episode of the MASONRY STRONG Podcast, Rob McKay from Instone joins the show to talk about his story as well as the processes and procedures of manufacturing natural stone. Getting Started in Masonry: Rob’s Story Rob entered the masonry field by

Justin Stengel
The MASONRY STRONG Podcast
Read More