SDS/2 vs Tekla Structures for Steel Detailing: An Honest Comparison

Neither is better in general. SDS/2 tends to suit fabricator-focused structural and miscellaneous steel packages where automated connections and fabrication outputs matter most. Tekla Structures tends to suit projects that mix steel with concrete, or where a contractor requires native Tekla models for coordination. The right choice depends on your project, your partners and your downstream workflow.

A note on bias: Vertex runs SDS/2 exclusively, so it has a stake in this question. The comparison below sticks to capabilities both vendors describe publicly, avoids market share claims, and includes the situations where Vertex would be the wrong choice because Tekla is the better fit.

Both platforms build a 3D model and generate drawings, reports and NC files from it, so either can produce a complete fabrication package. They differ in scope and emphasis: SDS/2 concentrates on steel and connection automation, while Tekla Structures, developed by Trimble, covers steel and concrete and places more weight on multi-party BIM collaboration and customization.

Version-specific features change with each release, so confirm current capabilities with each vendor before making a purchasing decision.

SDS/2 fits best on steel packages where connections drive the detailing effort: framing with many connections, repetitive shear connections that benefit from automation, and jobs where structural and miscellaneous steel belong in one model. It also fits shops whose downstream workflow is built around drawings, bolt lists and NC files rather than exchanging native models with other parties.

Typical situations where SDS/2 is a strong fit:

• A fabricator detailing steel buildings where connection consistency across hundreds of joints matters
• Packages that combine primary framing with stairs, rails and platforms in the same model
• Shops that need DSTV NC files for beam lines and KISS files for fabrication management software
• Projects where the fabricator's deliverables are drawings and machine files, not a shared native model

Tekla Structures fits best on projects that go beyond structural steel or that revolve around a shared native model: steel combined with precast or cast-in-place concrete, large multi-party BIM projects where the contractor requires Tekla models, and teams that already exchange native Tekla files with engineers, erectors or other detailers. Heavy customization through its API is another strength.

Typical situations where Tekla Structures is the better fit:

• A project where steel and concrete, precast or reinforcement are modeled together
• A contractor or owner that specifies native Tekla models as a deliverable
• A detailing team split across several firms that all work in Tekla
• A fabricator with in-house detailers in Tekla who need to edit the outsourced model directly

In the last case, a partner that runs only SDS/2, such as Vertex, is not the right choice. Deliverables like PDFs, NC files and IFC exports do not replace an editable native model if your own detailers need to keep working in it.

Software changes drawing quality far less than the detailer does. Both SDS/2 and Tekla Structures can produce fabrication-ready packages, and both can produce drawings with wrong dimensions, missing welds or mismatched marks. Detailer skill, knowledge of AISC 303 and AISC 360, an independent checking process and well-defined shop standards decide what reaches your shop floor.

Judge a detailing partner on output, not on the logo of the software. Ask for sample drawings of a structure like yours, a description of how drawings are checked before release, and an explanation of how revisions keep drawings, bolt lists and NC files in step.

It matters only if you need an editable native model. If your deliverables are PDF drawings, bolt lists, material takeoffs and NC files, the platform that produced them rarely matters to your shop or your beam line. If your in-house detailers must open and keep editing the model, the detailer must work in your platform.

Settle this at intake by listing the deliverables and formats you need:

IFC carries geometry and properties for coordination, but it is not a substitute for a native detailing model with its connections and drawing settings intact.

Choose a detailer on the deliverables you need, then on the quality of their output; software comes third. Start by deciding whether you need a native model or only drawings and machine files, confirm the NC format your equipment reads, and then compare sample drawings, checking processes and pricing between partners that meet those requirements.

• Decide whether you need an editable native model or drawings, reports and NC files
• Confirm your NC file format, machine requirements and fabrication management software
• Ask for sample drawings from a comparable structure
• Ask who checks drawings, against what, and whether corrections are back-checked
• Compare pricing on the same scope, including revisions and NC files

The guide to vetting a steel detailing partner turns this into a full checklist, and NC files and CNC integration covers what to agree about machine output.

Vertex works only in SDS/2 as a specialization: a team that details in one platform every day learns its connection tools, drawing templates, report engine and NC exports more deeply than a team switching platforms per project. The lead detailer has 8 years of SDS/2 experience. The tradeoff, as this comparison shows, is that Vertex cannot deliver native Tekla models.

If your project needs drawings, reports, NC files and IFC exports prepared to AISC standards, see SDS/2 detailing and 3D modeling. If it needs a native Tekla model, choose a partner who runs Tekla. Either way, the published steel detailing rates are a useful benchmark for comparing quotes.