The Simpson CJT4ZS (CJTZ) is a 12-gauge ZMAX galvanized concealed joist tie engineered to create strong, hidden connections between a joist and a header, post, or beam. Designed for versatility, the CJTZ can be installed three ways: with no routing of the header, post, or beam; with a routed header or post; or with a routed beam. Constructed from 12-gauge steel with a ZMAX galvanized finish, this connector delivers superior corrosion resistance suited for exterior environments and treated-wood applications. The CJT4ZS variant comes supplied with short pins (1/2 in. x 2-3/4 in.) and all required SDS screws - no additional hardware needed.

Key Features

• Concealed connector system - part of a system that includes the CPTZ and CBTZ for fully hidden structural connections
• Three installation methods - no routing, routed header/post, or routed beam for flexible job-site use
• Short dowel design - 1/2 in. x 2-3/4 in. short pins sized for 3-1/8 in. glulam beams, 4x sawn lumber, or 3-1/2 in.-wide PSL
• Center dowel in beam - center in beam to provide maximum beam width when using short dowels
• 12-gauge steel construction - heavy-duty gauge for reliable structural performance
• ZMAX galvanization - offers extra corrosion resistance compared to standard galvanized products, ideal for exterior and treated-wood applications
• Complete hardware included - supplied with all dowels and screws required; screws require a hex-head driver
• Made in the United States

Specifications

• Manufacturer Part Number (MPN): CJT4ZS
• Brand: Simpson Strong-Tie
• Series: CJTZ
• Connector Type: Concealed Joist Tie
• Steel Gauge: 12-Gauge
• Finish / Coating: ZMAX Galvanized
• Pin (Dowel) Size: 1/2 in. diameter x 2-3/4 in. length (Short)
• Fastener Drive Type: Hex-head driver (for included SDS screws)
• Country of Origin: United States

Approved Applications

The Simpson CJT4ZS concealed joist tie with short pins is approved for use with the following lumber types only:

• Glulam (glued-laminated) beams - 3-1/8 in. width
• 4x sawn lumber (well dried)
• Composite lumber - PSL (Parallel Strand Lumber), LSL (Laminated Strand Lumber), and LVL (Laminated Veneer Lumber), 3-1/2 in. wide

Important installation notes:

• Install only in glulam, composite lumber (PSL, LSL, and LVL), or well-dried lumber.
• Dowels aligned across the grain may cause splitting if the wood shrinks excessively - proper lumber selection and moisture content are critical.
• Center the dowel in the beam to maximize beam width when using short dowels.

What's Included

The Simpson CJT4ZS package includes all hardware required for a complete installation:

• Short pins - 1/2 in. diameter x 2-3/4 in. length dowels
• Strong-Drive SDS screws - all screws required for installation

Note: Screws require a hex-head driver for installation.

Frequently Asked Questions

What types of lumber are compatible with the CJT4ZS concealed joist tie?

The CJT4ZS is designed for use with glulam, composite lumber (PSL, LSL, and LVL), or well-dried sawn lumber. Specifically, the short dowels (1/2 in. x 2-3/4 in.) are sized for 3-1/8 in. glulam beams, 4x sawn lumber, or 3-1/2 in.-wide PSL. Installation in green or wet lumber is not recommended, as dowels aligned across the grain may cause splitting if the wood shrinks excessively.

What hardware is included with the CJT4ZS, and what tools are needed for installation?

The CJT4ZS comes supplied with all dowels and screws required for installation - no additional hardware needs to be purchased separately. The included short pins measure 1/2 in. in diameter by 2-3/4 in. in length. A hex-head driver is required to install the included screws.

What are the three installation methods available for the CJTZ concealed joist tie?

The CJTZ can be installed three ways: with no routing of the header, post, or beam; with a routed header or post; or with a routed beam. This flexibility allows the connector to accommodate different job-site conditions and design requirements while maintaining a concealed appearance.

Why does the CJT4ZS feature a ZMAX galvanized finish, and where is it appropriate to use?

The ZMAX galvanized coating provides extra corrosion resistance compared to standard galvanized products, making the CJT4ZS well suited for exterior applications and installations involving treated wood, where standard coatings may be insufficient to resist moisture and chemical exposure.