The Simpson Strong-Tie ATRM 3/8 in. x 18 in. All-Thread Rod, Grade 55 is a fully threaded steel rod engineered as a tension transfer element for structural systems designed to resist seismic and wind forces. Built to Grade 55 specifications with ASTM A36 steel, this all-thread rod delivers a continuous and reliable load path from roof to foundation - making it a trusted component in continuous rod tiedown systems for shearwall overturning restraint, uplift restraint systems for roof applications, and adhesive anchor rod installations.

Key Features

• Precut to 18 in. length - ready to install out of the box, saving layout and cutting time on the job site
• Meets Grade 55 specifications (ASTM A36; Fy = 55 ksi and Fu = 75 ksi) - delivers medium-strength tensile performance suited for structural tiedown and uplift restraint applications
• UNC Class 2A thread specification - ensures broad compatibility with standard nuts, couplers, and bearing plates used in continuous rod tiedown assemblies
• Fully threaded along the entire 18 in. length - allows flexible positioning of hardware anywhere along the rod, simplifying installation in varied framing conditions
• Uncoated black steel construction - provides a straightforward, cost-effective option for interior and protected structural applications where additional corrosion coating is not required
• 3/8 in. rod diameter - a compact size that fits tight framing bays while still providing the structural capacity required for shearwall and roof uplift systems

Why This Product

• Designed specifically as a tension transfer element for seismic and wind force resistance, this threaded rod is purpose-built for structural tiedown systems - not a generic hardware fastener repurposed for structural use
• The precut 18 in. length eliminates field cutting and threading, reducing labor time and the risk of measurement errors in continuous rod tiedown and uplift restraint assemblies
• Its versatility extends beyond shearwall systems - this all-thread rod can also be used as an adhesive anchor rod, giving contractors a single product that serves multiple structural applications on the same project
• Made in the United States to ASTM A36 standards with Grade 55 certification, this rod meets the material specification requirements commonly referenced in engineered structural designs for wind and seismic load paths

Specifications

• Brand: Simpson Strong-Tie
• MPN: ATRM3-1.5
• Rod Diameter: 3/8 in.
• Rod Length: 18 in.
• Grade: Grade 55
• Thread Specification: UNC Class 2A
• Material: Uncoated Steel
• Finish: Uncoated Steel
• Color: Black
• Steel Standard: ASTM A36
• Yield Strength (Fy): 55 ksi
• Ultimate Tensile Strength (Fu): 75 ksi
• 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 applications
• Adhesive anchor rod installations
• Structural systems designed to resist seismic forces
• Structural systems designed to resist wind forces

Frequently Asked Questions

What structural systems is this all-thread rod designed for?

This rod is designed for use as a tension transfer element in structural systems that resist seismic and wind forces. It can be used in a continuous rod tiedown system for shearwall overturning restraint, an uplift restraint system for roof applications, or as an adhesive anchor rod in various other structural configurations.

What thread specification does this rod use?

The ATRM3-1.5 uses a UNC Class 2A thread specification. This is a standard unified national coarse thread class that is compatible with a wide range of structural hardware components including nuts, couplers, and bearing plates commonly used in tiedown assemblies.

What are the steel strength properties of this rod?

This rod meets Grade 55 specifications and conforms to ASTM A36 with a yield strength (Fy) of 55 ksi and an ultimate tensile strength (Fu) of 75 ksi. These values define it as a medium-strength threaded rod suitable for the structural load path demands of shearwall and roof uplift restraint systems.

Does this rod come precut or does it need to be cut to length?

This rod comes precut to 18 in. (1.5 ft) for convenience. No field cutting or threading is required, allowing for faster installation in continuous rod tiedown and uplift restraint applications.