unistrut connecting strut to bar joists
 
One of the common questions we receive involves attaching Unistrut channel to bar joists. There are a variety of different ways to secure strut to bar joists, so choosing the best strategy boils down to the task at hand.  
 
In some instances, obstructions,such as conduit, pipes, and HVAC ducts positioned above or below the joist make us favor one method over another.  In other scenarios, the preferred attachment method boils down to the personal choice of your engineer. 
 
The good news is that we illustrate 3 time-tested techniques for connecting Unistrut channel to bar joists below, which means you can choose the strategy that best suits your specific needs. 
 

Unistrut Bottom Connection with Clamp Attachment


The most common strategy is a standard bottom chord connection, as shown below:

Unistrut bottom attachment of strut to bar joist image 1

 

Unistrut bottom attachment of strut to bar joist image 2

 

Unistrut bottom attachment of strut to bar joist image 3

 

Connecting With Threaded Rod


To connect with threaded rod, you need a “split” or opening in the bottom chord. This is useful when you have interferences (often conduit or copper) running along the joist, and you cannot use the beam clamps. You can put strut on the top or bottom, and use threaded rod, a plate washer, etc.  Threaded rod connection is illustrated in the next three images shown below:

Unistrut Threaded Rod Connection - Strut to Channel 1

 

Unistrut Threaded Rod Connection - Strut to Channel 2

 

Unistrut Threaded Rod Connection - Strut to Channel 3

 

Joist Wrap Connection Method


When you cannot attach to the bottom chord (e.g., a requirement of the engineer of record), you need to transfer the load to the top chord with a joist wrap technique shown in the images below:

Unistrut Strut to Bar Joist - Joist Wrap 1

 

Unistrut Strut to Bar Joist - Joist Wrap 2

 

Unistrut Strut to Bar Joist - Joist Wrap 3

 

As always, if you have additional questions about connecting Unistrut to bar joists, or have suggestions for future Tech Talk tips, feel free to get in contact or give us a call on 0121 706 7777. Have a look at our full online Unistrut offering here.