Select heavy duty fiberglass grating by its exact mesh, bar section, clear span and design load. Strongrate’s catalog marks selected molded configurations as HD. Compare those specification rows first, then confirm the matching load-table designation in the project submittal. The HD label alone does not establish a forklift, truck or other vehicle rating.
Catalog configurations marked HD
The square-mesh table identifies HD rows at 2" (50 mm), 2-3/8" (60 mm), 2-9/16" (65 mm) deep. The rectangular-mesh table has a separate HD row at 1" (25 mm) deep. Depth alone does not identify a heavy-duty configuration: retain the mesh, bar widths and weight together when comparing an alternative or ordering a replacement.
| Mesh | Depth | Bar width (as printed) | Weight | Open area | Span direction | Standard panel sizes |
|---|---|---|---|---|---|---|
| 1-1/2" × 1-1/2" (38 × 38 mm)1 | 2" (50 mm) heavy duty1 | 3/8" / 5/16" (9.5 / 7.5 mm)1 | 8.2 lb/ft² (40.0 kg/m²)1 | 56%1 | — | 4 ft × 12 ft (1220 × 3660 mm); 4 ft × 8 ft (1220 × 2440 mm); 3 ft × 10 ft (921 × 3050 mm)1 |
| 1-1/2" × 1-1/2" (38 × 38 mm)1 | 2-3/8" (60 mm) heavy duty1 | 3/8" / 5/16" (10.5 / 8.5 mm)1 | 9.8 lb/ft² (48.0 kg/m²)1 | 54%1 | — | 4 ft × 12 ft (1220 × 3660 mm); 4 ft × 8 ft (1220 × 2440 mm); 3 ft × 10 ft (921 × 3050 mm)1 |
| 1-1/2" × 1-1/2" (38 × 38 mm)1 | 2-9/16" (65 mm) heavy duty1 | 7/16" / 3/8" (11.0 / 9.0 mm)1 | 10.7 lb/ft² (52.0 kg/m²)1 | 52%1 | — | 4 ft × 12 ft (1220 × 3660 mm); 4 ft × 8 ft (1220 × 2440 mm); 3 ft × 10 ft (921 × 3050 mm)1 |
| 1" × 4" (25 × 102 mm)1 | 1" (25 mm) heavy duty1 | 3/8" / 5/16" (9.5 / 8.0 mm)1 | 3.2 lb/ft² (15.6 kg/m²)1 | 67%1 | Panel width1 | 4 ft × 12 ft (1220 × 3660 mm); 3 ft × 10 ft (921 × 3050 mm)1 |
Notes
- 1Values as printed in the factory catalog (2023).
For the rectangular HD configuration, the catalog specifies spanning in the panel-width direction. Mark bearing direction and support edges on the cutting drawing before optimizing panel yield. Compare the standard and HD versions on rectangular-mesh molded grating; do not substitute one for the other from a matching overall depth.
The 2-inch square-mesh product belongs to a different catalog family. A nominal depth shared by both families does not make their bar geometry, weight or load response interchangeable. For an equivalent-product submission, ask the supplier to identify the exact configuration and the supporting load table, then have the project engineer review them against the original design criteria.
Read HLC deflection data with the exact source designation
The following tables reproduce only the HLC entries printed as “38x38” mesh, “60” depth (2-3/8" (60 mm)). The catalog specification table uses a different mesh notation. A similar mesh name or matching depth does not establish that the specification row and load-table row describe the same bar section. Record the factory-approved mapping in the submittal before using these values for design.
Read the deflection at the actual clear span for the applicable load case, rather than selecting from the largest printed load. Uniform loading and a concentrated point load are separate checks. These are catalog data for static loads at ambient temperature. The catalog’s dynamic-load reduction does not turn them into wheel-load or vehicle-use approval.
| Clear span | 31 psf (150 kg/m²) | 72 psf (350 kg/m²) | 102 psf (500 kg/m²) | 154 psf (750 kg/m²) | 205 psf (1,000 kg/m²) | 307 psf (1,500 kg/m²) | 512 psf (2,500 kg/m²) | Max load, psf (kg/m²) |
|---|---|---|---|---|---|---|---|---|
| 11-13/16" (300 mm) | — | — | — | — | — | — | — | — |
| 17-3/4" (450 mm) | — | — | 0.02" (0.41 mm) | 0.02" (0.61 mm) | 0.03" (0.82 mm) | 0.05" (1.22 mm) | 0.08" (2.03 mm) | 12,423 (60,654) |
| 23-5/8" (600 mm) | 0.01" (0.33 mm) | 0.02" (0.41 mm) | 0.02" (0.62 mm) | 0.04" (0.92 mm) | 0.04" (1.12 mm) | 0.11" (2.86 mm) | 0.28" (7.14 mm) | 7,444 (36,344) |
| 29-1/2" (750 mm) | 0.02" (0.43 mm) | 0.04" (1.02 mm) | 0.06" (1.52 mm) | 0.09" (2.29 mm) | 0.19" (4.75 mm) | 0.28" (7.13 mm) | — | 4,758 (23,229) |
| 35-7/16" (900 mm) | 0.03" (0.68 mm) | 0.07" (1.83 mm) | 0.11" (2.84 mm) | 0.17" (4.27 mm) | 0.25" (6.41 mm) | 0.38" (9.62 mm) | — | 3,302 (16,122) |
| 47-1/4" (1200 mm) | 0.09" (2.37 mm) | 0.13" (3.3 mm) | 0.19" (4.71 mm) | 0.28" (7.07 mm) | 0.37" (9.43 mm) | 0.56" (14.15 mm) | — | 1,946 (9,499) |
Notes
- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.
| Clear span | 331 lb (150 kg) | 772 lb (350 kg) | 1,102 lb (500 kg) | 1,653 lb (750 kg) | 2,205 lb (1,000 kg) | 3,307 lb (1,500 kg) | 5,512 lb (2,500 kg) | 6,614 lb (3,000 kg) |
|---|---|---|---|---|---|---|---|---|
| 11-13/16" (300 mm) | — | — | — | — | — | — | — | — |
| 17-3/4" (450 mm) | — | — | — | 0.01" (0.37 mm) | 0.02" (0.49 mm) | 0.03" (0.64 mm) | 0.04" (1.01 mm) | 0.05" (1.25 mm) |
| 23-5/8" (600 mm) | — | 0.01" (0.37 mm) | 0.02" (0.48 mm) | 0.03" (0.76 mm) | 0.04" (1.08 mm) | 0.06" (1.46 mm) | 0.10" (2.43 mm) | 0.11" (2.92 mm) |
| 29-1/2" (750 mm) | 0.01" (0.3 mm) | 0.03" (0.7 mm) | 0.04" (0.9 mm) | 0.06" (1.43 mm) | 0.08" (2.09 mm) | 0.11" (2.84 mm) | 0.19" (4.73 mm) | 0.22" (5.68 mm) |
| 35-7/16" (900 mm) | 0.02" (0.42 mm) | 0.04" (1.03 mm) | 0.05" (1.32 mm) | 0.08" (2.1 mm) | 0.12" (3.11 mm) | 0.17" (4.22 mm) | 0.28" (7.03 mm) | 0.33" (8.44 mm) |
| 47-1/4" (1200 mm) | 0.03" (0.7 mm) | 0.07" (1.77 mm) | 0.10" (2.47 mm) | 0.14" (3.59 mm) | 0.21" (5.27 mm) | 0.28" (7.16 mm) | 0.45" (11.39 mm) | — |
Notes
- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.
Use the load-table reading guide to distinguish span, applied load and resulting deflection. For a wheel-loaded trench or access opening, submit the wheel load, contact area, travel direction, frequency and support arrangement for engineering review. The selection questions for trench covers and drain grates explain that separate application review.
Choose the surface and resin after the load case
Strongrate’s molded-grating range includes concave and gritted surfaces, plus solid covers with checker or grit finishes. Specify the finish with the exact HD profile. A covered grating panel requires a review of the complete covered assembly; an open-panel deflection table does not establish the performance of an added cover.
For corrosive service, identify the chemical, concentration, temperature and exposure duration before selecting a resin system. Where the project also specifies static control, review conductive molded grating as a separate electrical requirement. For an accessible walkway, compare mini-mesh clear openings rather than assuming a heavier panel meets the opening requirement.
Prepare an engineering and purchasing submittal
- Product identity: catalog mesh, HD depth, bar widths, resin and walking surface.
- Support drawing: clear spans, bearing direction, bearing lengths, openings, cutouts and panel edges.
- Design criteria: uniform, point or line loads; any wheel loading; deflection limit; impact and service temperature.
- Piece schedule: finished dimensions, quantity, fastening details and lifting or removable-panel requirements.
- Delivery requirements: destination ZIP code, required date, packaging and the shipping terms used for price comparison.
Strongrate products are made in Nantong, China, and ship from China. Use the factory-direct ordering guide to plan the purchasing sequence. Compare quotations against the same drawing, profile and delivery basis with the grating quote comparison tool. A price per panel is useful only when panel dimensions and the supplied configuration agree.
Request a quote
Request a quote with the HD profile, support drawing, load criteria, finished-piece schedule and delivery ZIP code. Quotes within 1 business day (US Central time).
Sources
- Strongrate product catalog “Your Best FRP Solution” (Sep 2023): printed pages 7, 10, 13 and 69–71 (accessed Oct 19, 2026)
- Strongrate factory product listing: heavy-duty molded FRP grating (accessed Oct 15, 2026)