Connectors in Cold-Formed Steel Wall framing

In cold-formed steel framing, a wide variety of connectors are used depending on the configuration of the structure (parapet, cornice, kicker, etc.). This blog is limited to the connectors used to attach cold-formed steel wall studs to floors or other structural components of a building such as structural/hot rolled steel or concrete slab. These connectors can be categorized in two main groups based on the function of framing in the building:

• Rigid connectors: used in load-bearing walls.
• Deflection connectors: used in non-load-bearing exterior walls.

Unlike a load-bearing wall, which is designed to resist wind load perpendicular to the plane of the wall and to transfer gravity load from floor to floor or floor to foundation, a non-load bearing exterior wall is designed to resist only wind load. Therefore, the other components to which non-load-bearing wall studs are attached must be allowed to move vertically without crushing wall studs.

In North America, there are three main manufacturers of cold-formed steel connectors: Clark Dietrich, Simpson Strong-Tie, and The Steel Network (TSN).

Rigid Connectors (Clips)
The most common rigid connectors provided by the three manufacturers to use at the top and bottom of load-bearing walls are presented in Table 1 below:

 

Table 1. Rigid Clips

Manufacturer	Clark Dietrich	Simpson	TSN
Clip Name	Easyclip S-Series Clip	RCA Rigid Connector Angles	StiffClip AL
Product Code	SXXY	RCA22Y/XX	ALYYY

• XX is the clip gauge (mil), e.g., S547, RCA227/54 for 16-ga (54 mil).
• Y is the clip width for S-Series and RCA or the width of the stud for AL.

S-Series and RCA are also called short legs rigid clips, with respectively 1-1/2-in legs and 2-in legs (shown in the product code as RCA22). AL clips have 1-1/2”x3” legs where the long leg must be attached to a stud. Clark Dietrich long legs clips (EXXY: 1-1/2”x4” legs) and Simpson long legs clips (RCA33Y/XX: 3”x3” legs) are used for other applications (fascia, soffit, hung framing, etc.) where the gap between the framing and the attachment is too wide for short legs clips.

Top of wall Deflection clips, used in place of or in combination with deflection track.Deflection Connectors (Clips)
There are mainly two types of deflection clips depending on the application:

• Deflection clips for bypass framings.

Top of Wall Deflection Clips
The most common deflection connectors provided by the three manufacturers to use at top of non-load-bearing walls are presented in Table 2 below:

Table 2. Top of Wall Deflection Clips

Manufacturer	Clark Dietrich	Simpson	TSN
Clip Name	Fast Top Clip	Head-of-Wall Slide-Clip	VertiClip
Product Code	FTX	SCWX.XX	SLXXX

• X represents the width of the clip for FT and SW or the width of the stud for SL.

FT Clips allow a vertical movement up to 2-1/2” (1-1/4” upward and 1-1/4” downward). SW clips offer a vertical movement of 2” (1” upward and 1” downward). SL clips allow a total vertical movement of 1-1/2” (3/4” upward and 3/4” downward) or 3” (1-1/2” upward and 1-1/2” downward).

Bypass Deflection Clips
There is a broad range of bypass deflection clips depending on the gap between stud and the point of attachment, and the type of attachment to the structural component: top of slab (bottom of steel beam flange), face of slab (steel beam web).

The most used deflection clips provided by the three manufacturers are presented in Tables 3.1 (short legs clips) and 3.2 (long legs clips).

Table 3.1 Bypass Deflection connectors

Manufacturer	Clark Dietrich	Simpson	TSN
Clip Name	FastClip Slide Clip	Bypass Framing Slide-Clip	VertiClip
Product Code	FCSCX.X-YY	SCXX-5/YY	SLBXXX

 

Table 3.2 Long Legs Bypass Deflection connectors

Manufacturer	Clark Dietrich	Simpson	TSN
Clip Name	Extended FastClip	Bypass Framing Slide-Clip	VertiClip
Product Code	FCECX-YY	SCB4XX or MSCB4XX	SLSXXX

• X is the length of the leg to attach to stud.
• Y is the gauge (mil) of the clip material.
• For Simpson long leg clips, all SCB clips are 16-ga and MSCB clips are 14-ga.