D1.8 Certified Structural Steel
for Seismic Projects That
Can’t Cut Corners
For general contractors, engineers and developers who need a steel erector that understands seismic intent.
Licensed Multi-State
Integrity. Safety. Quality.
AWS Certified Welding Inspector
AWS D1.8 Seismic Steel
Category 5 Steel provides AWS D1.8 certified structural steel fabrication and erection for commercial projects in seismically active markets across Washington, Oregon, California, Utah, and beyond. With an AWS Certified Welding Inspector on staff and documented experience building moment frames, CJP weld assemblies, and installing buckle-resistant bracing systems, we deliver the quality that seismic projects require from bid through final inspection.
why seismic steel Is different
D1.8 is a supplemental code to D1.1 that governs structural steel welding in the USA. It is specifically for seismic applications and applies in areas with active faults as well as emerging markets where seismic activity may be caused by fracking.
A fabricator certified only under AWS D1.1 can produce structurally sound welds for conventional construction. Seismic connections — moment frames, buckle-resistant bracing frames (BRB), etc — are designed to stand up to the stresses of an earthquake without failing.
That’s why municipal authorities in seismically active areas scrutinize seismic steel documentation the way they do. A fabricator who says they can do D1.8 work without the certification and documentation to back it up is a liability.
what d1.8 certification
actually requires
Welding Procedure Specifications (WPS)
Every joint on a project with seismic requirements requires a qualified or prequalified WPS. We maintain WPS records for the connection types our projects require.
AWS Certified Welding Inspector
D1.8 work requires CWI oversight throughout fabrication, not only in final review. Our AWS CWI is on the shop floor during critical seismic weld production, maintaining the inspection records your EOR and municipal authorities will expect.
Inspection Records
Every seismic connection is inspected and documented. The paper trail covers material certifications, WPS compliance, preheat verification, and CWI sign-off on each critical weld.
Seismic systems understanding
The most important differentiator isn’t the paperwork — it’s whether the fabrication team understands why the connection is detailed the way it is. Our team brings expertise from building moment frames, BRB systems, and SFRS assemblies.Seismic Systems We
Fabricate and Erect
Buckle-Resistant Bracing (BRB)
BRB systems are increasingly specified by structural engineers for mid-market commercial buildings. We have field-installed numerous BRB systems and understand how to make these projects run smoothly.
Special Moment Frames (SMF)
Moment frame systems are the backbone of seismic design in industrial and commercial construction across the West Coast. We have built SMF systems for commercial, healthcare, and educational projects across seismically active markets.
Complete Joint Penetration (CJP) Welds
CJP welds on seismic connections are among the most inspection-intensive welds in structural steel construction. Joint preparation, fit-up tolerances, preheat requirements, and post-weld inspection protocols are all governed by D1.8.
Structural Frames with Seismic Detailing
Many commercial projects in seismic-active regions require structural steel connections designed and detailed to seismic performance standards. We fabricate and erect these frames to specification.
Where We Work
Markets Where We Deliver
Seismic Steel Work
Healthcare & Medical Facilities
Hospital and medical office construction in WA, OR, CA, and UT sits at the intersection of seismic demand and tight scheduling. Our CWI credentials, D1.8 certification, and complete documentation system are built for exactly this environment.
Commercial Office & Corporate Campus
Our design-assist capability allows structural engineers and design-build GCs to engage us early — reviewing preliminary structural concepts and providing constructability input before issued-for-construction documents.
Government & Public Works
Federal and state projects in seismic zones require documented safety programs, multi-state licensing, and seismic welding certification with a verifiable paper trail. Our credentials are organized for the pre-qualification process public works contracts demand.
Retail, Mixed-Use & Industrial
Seismic requirements don’t disappear on retail or industrial projects. Tilt-up and structural steel hybrid systems, mixed-use podium structures, and industrial facilities in high seismic hazard areas all require the same D1.8 discipline.
Our Process
Our Seismic Project Process
Pre-Qualification & Scope Review
We provide a complete pre-qualification package on request — D1.8 certification, AWS CWI credentials, WPS documentation, state licensing, OSHA trainer credentials, and project references. We review structural drawings and return a preliminary bid scoped to the actual seismic requirements.
Design-Assist & Detailing Coordination
For projects where structural documents are still in progress, we can participate in pre-construction coordination, review preliminary moment frame or BRB concepts, and provide fabrication and erection input before documents are issued for permit.
D1.8 Fabrication with CWI Oversight
Fabrication proceeds under qualified WPS for each seismic connection type. Our AWS CWI is present throughout critical seismic weld production — maintaining weld maps, recording inspection results, and producing the documentation package your AHJ will review.
Field Erection & Final Documentation
Our installation crews work in all weather conditions to maintain schedules. Final documentation — CWI records, weld maps, material certifications — is delivered organized for project closeout and AHJ final review.
What We Deliver
Seismic Steel Documentation
What We Provide
Pre-Construction
AWS D1.8 certification documentation, AWS Certified Welding Inspector credentials, Qualified and Prequalified Welding Procedure Specifications for all required connection types, material documentation, state licensing verification for project jurisdiction.
During Fabrication
CWI inspection records for each critical weld, preheat and interpass temperature records, material certifications (MTRs) for all seismic steel, nondestructive testing records where required by specification.
At Project Closeout
Complete organized documentation package covering all of the above, formatted for municipal submission, owner file, and structural engineer record retention.
COMMON QUESTIONS
Ready to Talk
About Your Project?
If your project is in the design phase, the bidding phase, or you’re qualifying subs for upcoming work — send us your drawings and scope and we’ll come back with a preliminary bid.