The Simpson Strong-Tie ATRM3-4 All-Thread Rod is a fully threaded steel rod engineered as a tension transfer element for structural systems designed to resist seismic and wind forces. Manufactured by Simpson Strong-Tie, this 3/8 in. x 48 in. Grade 55 threaded rod delivers a continuous and reliable load path from roof to foundation - making it a critical component in continuous rod tiedown systems for shearwall overturning restraint and uplift restraint systems for roofs. Its versatility also extends to use as an adhesive anchor rod, giving contractors and engineers a multi-application fastening solution in a single precut length.

Key Features

• Precut 48 in. length - arrives ready to install with no cutting required on the jobsite, saving time during structural assembly
• Grade 55 specification (ASTM A36; Fy = 55 ksi, Fu = 75 ksi) - delivers the tensile and yield strength required for engineered seismic and wind resistance applications
• UNC Class 2A thread specification - ensures consistent thread form and fit for compatibility with standard nuts, couplers, and tiedown hardware
• Uncoated black steel construction - provides a clean, consistent surface suitable for interior structural use and adhesive anchor applications
• 3/8 in. rod diameter - sized for use within continuous rod tiedown and uplift restraint systems where precise dimensional compliance is required
• Fully threaded along entire 48 in. length - allows positioning and connection at any point along the rod, maximizing installation flexibility in shearwall and roof uplift assemblies

Why This Product

• Designed specifically as a tension transfer element for seismic and wind force resistance - this rod is engineered to perform where structural load path continuity from roof to foundation is a code requirement, not just a preference.
• The precut 48 in. length reduces field fabrication time and helps eliminate cut-length errors during installation in continuous rod tiedown systems or uplift restraint assemblies.
• Grade 55 steel with ASTM A36 material compliance meets the strength specifications demanded by structural engineers designing shearwall overturning restraint systems, reducing the need for substitution approvals.
• Multi-application capability - functions in continuous rod tiedown systems, roof uplift restraint systems, and as an adhesive anchor rod - making it a single stocking item that serves multiple structural needs on the same project.

Specifications

• Brand: Simpson Strong-Tie
• MPN: ATRM3-4
• Rod Diameter: 3/8 in.
• Rod Length: 48 in.
• Thread Type: UNC Class 2A
• Grade: Grade 55
• Material Standard: ASTM A36; Fy = 55 ksi & Fu = 75 ksi
• Material: Uncoated Steel
• Finish: Uncoated Steel
• Color: Black
• Product Class: Threaded Rod
• Quantity: 1
• Country of Origin: United States
• Prop 65: No

Approved Applications

• Continuous rod tiedown systems for shearwall overturning restraint
• Uplift restraint systems for roof structural assemblies
• Adhesive anchor rod applications
• Structural systems designed to resist seismic and wind forces

Frequently Asked Questions

What structural applications is the ATRM3-4 designed for?

The ATRM3-4 is designed as a tension transfer element for use in structural systems that resist seismic and wind forces. It is specifically suited for continuous rod tiedown systems providing shearwall overturning restraint, uplift restraint systems for roofs, and adhesive anchor rod applications.

What are the material strength properties of this all-thread rod?

This rod meets Grade 55 specifications with ASTM A36 material compliance - Fy = 55 ksi (yield strength) and Fu = 75 ksi (ultimate tensile strength). The thread form follows UNC Class 2A specification.

Is this rod precut or does it require field cutting?

The ATRM3-4 is precut to 48 in. (4 ft.) for convenience. No field cutting is required, allowing for faster and more accurate installation in tiedown and uplift restraint assemblies.

What is the finish on this threaded rod, and is it coated?

The ATRM3-4 is manufactured from uncoated black steel with no protective coating applied. This makes it well suited for interior structural applications and adhesive anchor installations where an uncoated surface is acceptable or preferred.