Material and product decision guide
Steel Grating vs Expanded Metal
Bar grating is assembled from load-carrying bearing bars and cross bars; expanded metal is slit and stretched from sheet or plate. The products need different design data.
Do not substitute one for the other from open-area appearance. Require the exact product designation, support layout, load case and manufacturer or standard data.
Side-by-side decision matrix
This matrix is a screening aid. It identifies what must be compared; it is not a substitute for the approved design or product data.
| Decision | Steel bar grating | Expanded metal |
|---|---|---|
| Manufacture | Separate bearing and cross bars are joined into a panel. | Sheet or plate is slit and expanded into strands and bonds. |
| Load path | Bearing bars span in a defined direction. | Strand orientation, style, sheet thickness and support govern. |
| Specification family | NAAMM MBG resources address metal bar grating. | NAAMM EMMA resources address expanded metal. |
| Openings | Bearing-bar and cross-bar spacing define the grid. | Diamond dimensions and strand geometry define the opening. |
| Substitution | Needs product-specific load and attachment data. | Needs product-specific load and attachment data. |
Choose Steel bar grating when
- The project calls for bar grating or its load-table format.
- Bearing direction and panel supports can be clearly defined.
- The opening pattern and fabrication details are acceptable.
All conditions still need confirmation against the exact panel, support, load case and governing specification.
Choose Expanded metal when
- The project calls for an expanded-metal style and designation.
- The exact mesh, strand and orientation data are available.
- Support and edge details match the selected product.
Ask the supplier to identify any qualification, exception or missing evidence before treating the option as equivalent.
Inputs required for a defensible comparison
A quotation cannot resolve the choice unless both suppliers receive the same technical basis. Include the following in the RFQ and record assumptions explicitly.
- Applicable MBG or EMMA product designation
- Bearing or strand direction
- Thickness, dimensions and open area
- Load, span, support and deflection
- Edges, attachment and corrosion protection
Related product information: Steel bar grating · Load and deflection basics. For preliminary sizing, use the load and deflection guide.
What this guide does not decide
It does not approve structural capacity, slip resistance, fire performance, chemical compatibility, electrical suitability, accessibility or legal compliance. Those decisions depend on the installed system, jurisdiction, test method and order-specific evidence reviewed by the responsible project team.
Primary references
Checked 2026-09-04. Confirm the edition and scope accepted by your project.