Bar Joist Method of attaching Unistrut Channel to Bar Joist

Attaching Unistrut to Bar Joist with Joist Wrap Method

Joist Wrap is the third and final method we will go over in our series on how to attach Unistrut channel to bar joist. In situations where the bottom chord cannot be attached to, or where the engineer has specified the top chord as the load bearing chord, the joist wrap method is the preferred way to safely and effectively transfer the load that would normally be born by the bottom chord to the top chord.

Download this Handy Connection Guide

UNISTRUT-JOIST-WRAP: How to Attach Unistrut to Bar Joist Using Joist Wrap Method

Which Hardware and Fittings Should I Use?

There are many factors that go into determining the proper channel, fittings and hardware combination to use in your joist wrap. Some of these factors include what has already been specified by the project engineer, the load requirements of the project, and whether there are any obstructions present.

Assembly Components

A list of all the components used in our example appears below. Actual components needed may differ, based on your specific projetc requirements. This example is meant for design purposes only. In this example we've chosen a low profile, Unistrut P3300, channel above the top chord, standard Unistrut P1000 for the vertical channel wrapping the joists, and Unistrut P1001, double strut, below the bottom chord.Joist Wrap Method of Attachment to Unistrut Channel - Top Chord View

  • Unistrut P3300 Low-Profile Channel (above top chord) - mounted above top chord as a connection point for the two vertical channels that wrap the bar joist on eother side
  • Unistrut P1000 Channel (one on either side of the bar joist) - positioned vertically on either side of bar joist, connects, perpendicularly, to the channel above the top chord and below the bottom chord
  • Unistrut P1001 Double Strut (belw bottom chord) - mounted to the two vertical channels wrapping the bar joist, below bottom chord
  • Unistrut P1326 90 Degree Brackets - used to make all channel to channel connections
  • Unistrut P3013 Channel Nuts - 1/2" channel nuts used to attach P1326 brackets to channel 
  • Joist Wrap Method of Attachment to Unistrut Channel - Bottom Chord ViewHHCS050 Hex Head Cap Screw - 1/2" Hex Head Cap Screw, used in conjunction with channel nuts, to secure channel and fittings together

Are There Other Methods of Attaching Unistrut to Bar Joist?

Yes there are! This is just one of three blog posts in our series on how to connect bar joist to strut channel. Using Unistrut joist wrap to attach Unistrut channel to a bar joist is typically reserved for projects where the load needs to be transferred to the top chord of the joist. However, there are several more popular methods, including attachment using joist clamps and threaded rod attachment, that rely on the bottom chord for load bearing.

Ultimately, the method that works best for your specific project may depend on a few key factors, such as:

  • What mechanical, electrical, plumbing and HVAC elements, or obstacles, are already in place
  • What your load requirements are
  • What has been requested by the project engineer

Other methods of Connecting Unistrut Channel to Bar Joist include:

RESOURCES


Installation

Download Connection Guide for UBS-JOIST-WRAP

Submittals

Drawings


DISCLAIMER

STANDARD DETAILS ARE FOR REFERENCE AND DESIGN PURPOSES ONLY, AND ARE NOT INTENDED FOR USE AS FULLY ENGINEERED SYSTEMS. ENGINEERED SYSTEMS MUST TAKE INTO ACCOUNT ACTUAL SITE CONDITIONS (SUCH AS: LOAD, ELEVATION, SIZE, SPACING, BUILDING STRUCTURE, EXISTING MEP STRUCTURES, ETC.) AND BE PURCHASED THROUGH UNISTRUT BUFFALO SUPPORTS, A DIVISION OF EBERL IRON WORKS, INC. 128 SYCAMORE STREET, BUFFALO, NEW YORK 14204. CONTACT UNISTRUT BUFFALO SUPPORTS: 1 (800) 285-3056 UNISTRUTSTORE.COM/REQUEST-QUOTE FOR A CUSTOM QUOTE TAILORED TO YOUR JOBSITE/PROJECT.