The Simpson Strong-Tie ATRM 1-1/8 in. x 36 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. By providing a continuous and reliable load path from roof to foundation, this all-thread rod plays a critical role in keeping structures secure under lateral loading conditions. Whether used in a continuous rod tiedown system for shearwall overturning restraint, an uplift restraint system for roof applications, or as an adhesive anchor rod, this threaded rod delivers the strength and versatility that structural applications demand.

Key Features

• Precut 36 in. length - ready to install without on-site cutting, saving time and reducing fabrication effort on the job.
• Grade 55 specification (ASTM A36; Fy = 55 ksi and Fu = 75 ksi) - delivers high tensile and yield strength, ensuring the rod can handle the demanding loads imposed by seismic and wind force systems.
• UNC Class 2A thread specification - a standardized thread profile that ensures consistent fit with compatible nuts, couplers, and bearing plates used in tiedown and uplift restraint systems.
• 1-1/8 in. rod diameter - a robust cross-section suited to heavy structural loads in shearwall overturning restraint and roof uplift restraint applications.
• Uncoated black steel finish - provides a clean, ready-to-use surface compatible with a wide range of structural connector hardware in interior and protected installations.
• Made in the United States - domestically produced to support quality control standards expected in engineered structural applications.

Why This Product

• Designed specifically as a tension transfer element for seismic and wind force-resisting systems, this rod is engineered to maintain a continuous load path from roof to foundation - addressing one of the most critical requirements in modern structural design.
• The precut 36 in. length eliminates the need for field cutting and threading, reducing labor time and the risk of field errors when installing a continuous rod tiedown system or uplift restraint system.
• With ASTM A36 material meeting Grade 55 strength values (Fy = 55 ksi and Fu = 75 ksi), this rod provides known, code-consistent mechanical properties that structural engineers can rely on when designing shearwall overturning restraint systems.
• Multi-application versatility - appropriate for continuous rod tiedown systems, roof uplift restraint systems, and adhesive anchor rod installations - means a single product can serve multiple roles across a project.

Specifications

• Brand: Simpson Strong-Tie
• MPN: ATRM9-3
• Product Class: Threaded Rod
• Rod Diameter: 1-1/8 in.
• Rod Length: 36 in.
• Material: Uncoated Steel
• Finish: Uncoated Steel
• Color: Black
• Thread Specification: UNC Class 2A
• Material Standard: ASTM A36
• Yield Strength (Fy): 55 ksi
• Ultimate Tensile Strength (Fu): 75 ksi
• Grade: Grade 55
• Quantity: 1
• Country of Origin: United States
• Prop 65: No

Approved Applications

• Continuous rod tiedown system (ATS) for shearwall overturning restraint
• Uplift restraint system (URS) 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 the ATRM9-3 designed to work with?

The ATRM9-3 is designed for use in structural systems that resist seismic and wind forces. It functions as a tension transfer element, providing a continuous load path from roof to foundation. Specific applications include continuous rod tiedown systems for shearwall overturning restraint, uplift restraint systems for roofs, and adhesive anchor rod installations.

What are the material and strength specifications for this all-thread rod?

The ATRM9-3 is manufactured from uncoated steel meeting ASTM A36 requirements at Grade 55 values, with a minimum yield strength (Fy) of 55 ksi and a minimum ultimate tensile strength (Fu) of 75 ksi. The thread profile conforms to UNC Class 2A specifications.

Does this rod come precut, or does it need to be cut to length in the field?

This rod comes precut to a length of 36 in. (3 feet) with a diameter of 1-1/8 in., so no field cutting or threading is required. The precut format is designed for convenience during installation in tiedown and uplift restraint systems.

Is this rod coated or treated for corrosion protection?

No - the ATRM9-3 is uncoated black steel with no applied corrosion-resistant finish. It is intended for use in applications where the installation environment does not require additional corrosion protection, such as interior or protected structural assemblies.