Material and product decision guide
Molded FRP vs Pultruded FRP Grating
Molded FRP is formed as an integral mesh panel; pultruded FRP uses continuous load-carrying bars assembled with cross members. Their load paths are not interchangeable.
Start with clear span, bearing direction, load case, opening layout and chemical exposure, then compare manufacturer data for the exact depth, resin and surface.
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 | Molded FRP | Pultruded FRP |
|---|---|---|
| Load path | Often provides two-direction panel action; verify product data. | Primarily directional through continuous bearing bars. |
| Layout | Mesh panel can simplify some multidirectional cut layouts. | Orientation must follow the bearing-bar direction. |
| Span selection | Use the exact molded panel table. | Use the exact pultruded series table. |
| Chemistry | Resin, glass, surface and exposure all matter. | Resin, glass, surface and exposure all matter. |
| Field work | Cutting, support and sealing follow manufacturer instructions. | Cuts must preserve the designed bearing members and supports. |
Choose Molded FRP when
- The panel layout benefits from a mesh construction.
- The exact product meets load, deflection and chemical requirements.
- Openings and support edges match the manufacturer's rules.
All conditions still need confirmation against the exact panel, support, load case and governing specification.
Choose Pultruded FRP when
- Directional capacity and span are suited to the support layout.
- Bearing direction can be controlled in drawings and installation.
- The specified series has verified data for the load case.
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.
- Molded or pultruded product designation
- Bearing direction and clear span
- Resin system and chemical exposure
- Surface, fire and electrical requirements
- Cutouts, clips, support and sealing
Related product information: Molded FRP grating · Pultruded FRP grating. 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.