---
title: "Rectangular Mesh Fiberglass Grating: 1x4 and 1x6 Specs"
description: "Rectangular mesh fiberglass grating, molded: 1\" × 4\" mesh 1\" deep and DNV-listed 1\" × 6\" mesh 1-1/2\" deep, with catalog weights, deflection tables, fire data."
url: https://www.strongrate.us/molded-fiberglass-grating/1x4-rectangular-mesh/
markdown: https://www.strongrate.us/molded-fiberglass-grating/1x4-rectangular-mesh.md
published: 2026-10-16
updated: 2026-10-17
---

[Home](https://www.strongrate.us/) › [Fiberglass grating](https://www.strongrate.us/fiberglass-grating/) › [Molded grating](https://www.strongrate.us/molded-fiberglass-grating/) › [Rectangular mesh](https://www.strongrate.us/molded-fiberglass-grating/1x4-rectangular-mesh/)

# Rectangular Mesh Fiberglass Grating, 1" × 4" and 1" × 6" Molded

_Updated Oct 17, 2026_

Strongrate's catalog lists two rectangular meshes: 1" × 4" (25 × 102 mm), 1" (25 mm) deep at 2.7 lb/ft² (13.0 kg/m²), also in heavy duty, and 1" × 6" (25 × 152 mm), 1-1/2" deep at 4.6 lb/ft² (22.5 kg/m²). Choose 1" × 4" to replace existing US rectangular grating; choose 1" × 6" for the DNV-listed vinyl ester model, flame spread index 10.

**DNV-listed model: 1" × 6" mesh, 1-1/2" deep**

| Specification | Value | Note |
| --- | --- | --- |
| DNV certificate designation | 25.4×152.4×38 mm | Inch sizes are North American nominals of the metric certificate designation. |
| Mesh and depth | 1" × 6" (25 × 152 mm), 1-1/2" (38 mm) deep | Inch sizes are North American nominals of the metric certificate designation. |
| Resin | Vinyl ester |  |
| ASTM E84-19a flame spread index | 10 | Result as listed on DNV certificate TAF0000191 Rev. 1 (ASTM E84-19a); applies to the 1" × 6" model only, not to a 1" × 4" product. |
| ASTM E84-19a smoke-developed index | 15 | Result as listed on DNV certificate TAF0000191 Rev. 1 (ASTM E84-19a); applies to the 1" × 6" model only, not to a 1" × 4" product. |
| Structural fire integrity | L0 per ASTM F3059-15 | As stated on the certificate; acceptance for a given location is case by case. |
| Glass content | 30–35% by total weight (all molded grating) |  |

**Strongrate catalog data: 1" × 4" and 1" × 6" rectangular-mesh molded grating**

| Mesh | Depth | Bar width (as printed) | Weight | Open area | Span direction |
| --- | --- | --- | ---: | ---: | --- |
| 1" × 4" (25 × 102 mm) [note 1] | 1" (25 mm) [note 1] | 1/4" / 3/16" (6.5 / 5.0 mm) [note 1] | 2.7 lb/ft² (13.0 kg/m²) [note 1] | 67% [note 1] | Width or length [note 1] |
| 1" × 4" (25 × 102 mm) [note 1] | 1" (25 mm) heavy duty [note 1] | 3/8" / 5/16" (9.5 / 8.0 mm) [note 1] | 3.2 lb/ft² (15.6 kg/m²) [note 1] | 67% [note 1] | Panel width [note 1] |
| 1" × 6" (25 × 152 mm) [note 1] | 1-1/2" (38 mm) [note 1] | 3/8" / 1/4" (9.0 / 6.5 mm) [note 1] | 4.6 lb/ft² (22.5 kg/m²) [note 1] | 63% [note 1] | Panel length [note 1] |

_As printed in Strongrate’s 2023 product catalog; confirmed in your quote and submittal drawings. The catalog prints two bar widths per depth without saying which is the top and which the bottom of the bar._

Notes:

1. Values as printed in the factory catalog (2023).

The DNV fire results cover the 1" × 6" vinyl ester model only, not the 1" × 4" mesh. The catalog also lists 1-1/2" × 4" and 1-1/2" × 6" meshes at 1-1/2" deep; name them in your quote request if you need them.

## What panel sizes are available?

- **1" × 4" (25 × 102 mm) mesh, 1" (25 mm) deep:** 4 ft × 12 ft (1220 × 3660 mm); 3 ft × 10 ft (921 × 3050 mm)
- **1" × 6" (25 × 152 mm) mesh, 1-1/2" deep:** 4 ft × 12 ft (1220 × 3660 mm); 3 ft × 10 ft (921 × 3050 mm)

Panel sizes as printed in Strongrate’s catalog. Send your layout or drawings with the quote request. Sizes and weights of every product: [fiberglass grating sizes, weight and open area](https://www.strongrate.us/resources/fiberglass-grating-sizes-weight-and-open-area/).

## How does rectangular mesh carry load?

A rectangular mesh has different bar spacing in each direction, so the catalog prints a span direction for each row: the standard 1" × 4" spans either way, the heavy-duty 1" × 4" across the panel width, and the 1" × 6" along the panel length. Read the deflection at your clear span below; halve the loads for impact. How to read the columns: [fiberglass grating load tables](https://www.strongrate.us/resources/fiberglass-grating-load-tables/).

**Uniform load deflection, Strongrate 1" × 4" mesh, 1" deep, standard and heavy duty (catalog pages 61–62, printed as 25 × 100 mm mesh)**

| Clear span | Depth | 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) | 1" (25 mm) | — | 0.01" (0.28 mm) | 0.01" (0.37 mm) | 0.02" (0.51 mm) | 0.02" (0.63 mm) | 0.03" (0.73 mm) | 0.04" (1.04 mm) | 5,397 (26,350) |
| 11-13/16" (300 mm) | 1" (25 mm) HD | — | — | — | 0.01" (0.26 mm) | 0.02" (0.53 mm) | 0.03" (0.79 mm) | 0.05" (1.32 mm) | 6,747 (32,940) |
| 17-3/4" (450 mm) | 1" (25 mm) | 0.02" (0.53 mm) | 0.03" (0.72 mm) | 0.05" (1.36 mm) | 0.09" (2.16 mm) | 0.11" (2.86 mm) | 0.14" (3.54 mm) | 0.28" (7.22 mm) | 3,098 (15,128) |
| 17-3/4" (450 mm) | 1" (25 mm) HD | 0.01" (0.29 mm) | 0.02" (0.51 mm) | 0.03" (0.76 mm) | 0.05" (1.27 mm) | 0.06" (1.53 mm) | 0.09" (2.29 mm) | 0.15" (3.82 mm) | 3,873 (18,910) |
| 23-5/8" (600 mm) | 1" (25 mm) | 0.03" (0.73 mm) | 0.04" (0.92 mm) | 0.07" (1.86 mm) | 0.10" (2.46 mm) | 0.14" (3.68 mm) | 0.22" (5.54 mm) | 0.36" (9.22 mm) | 2,599 (12,688) |
| 23-5/8" (600 mm) | 1" (25 mm) HD | 0.04" (0.89 mm) | 0.05" (1.27 mm) | 0.08" (2.03 mm) | 0.13" (3.3 mm) | 0.17" (4.32 mm) | 0.25" (6.35 mm) | — | 3,248 (15,860) |
| 29-1/2" (750 mm) | 1" (25 mm) | 0.06" (1.65 mm) | 0.11" (2.86 mm) | 0.15" (3.71 mm) | 0.22" (5.63 mm) | 0.33" (8.32 mm) | — | — | 2,079 (10,150) |
| 29-1/2" (750 mm) | 1" (25 mm) HD | 0.07" (1.87 mm) | 0.12" (3.06 mm) | 0.18" (4.57 mm) | 0.28" (7.12 mm) | 0.37" (9.41 mm) | — | — | 2,599 (12,688) |
| 35-7/16" (900 mm) | 1" (25 mm) | 0.08" (2.13 mm) | 0.14" (3.64 mm) | 0.26" (6.61 mm) | 0.39" (9.87 mm) | 0.49" (12.57 mm) | — | — | 1,493 (7,289) |
| 35-7/16" (900 mm) | 1" (25 mm) HD | 0.15" (3.87 mm) | 0.23" (5.84 mm) | 0.35" (8.89 mm) | — | — | — | — | 1,866 (9,111) |
| 47-1/4" (1200 mm) | 1" (25 mm) | 0.22" (5.62 mm) | 0.33" (8.37 mm) | 0.59" (14.91 mm) | — | — | — | — | 939 (4,587) |
| 47-1/4" (1200 mm) | 1" (25 mm) HD | 0.30" (7.62 mm) | 0.50" (12.71 mm) | — | — | — | — | — | 1,174 (5,734) |

_Cells are deflection under static load at ambient temperature, as printed in Strongrate’s 2023 catalog (mm), with inches converted; “—” means no value is printed. Halve the loads for impact or dynamic conditions. Confirm the values for your span in the submittal before final design._

Notes:

- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.

**Concentrated point load deflection, Strongrate 1" × 4" mesh, 1" deep, standard and heavy duty (catalog pages 62–63, printed as 25 × 100 mm mesh)**

| Clear span | Depth | 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) | 1" (25 mm) | 0.01" (0.29 mm) | 0.03" (0.69 mm) | 0.04" (0.99 mm) | 0.06" (1.5 mm) | 0.08" (2.13 mm) | 0.11" (2.89 mm) | 0.19" (4.74 mm) | — |
| 11-13/16" (300 mm) | 1" (25 mm) HD | — | 0.02" (0.52 mm) | 0.03" (0.74 mm) | 0.04" (1.13 mm) | 0.06" (1.6 mm) | 0.09" (2.17 mm) | 0.14" (3.56 mm) | — |
| 17-3/4" (450 mm) | 1" (25 mm) | 0.02" (0.47 mm) | 0.04" (1.1 mm) | 0.06" (1.43 mm) | 0.09" (2.25 mm) | 0.13" (3.2 mm) | 0.17" (4.33 mm) | — | — |
| 17-3/4" (450 mm) | 1" (25 mm) HD | 0.01" (0.35 mm) | 0.03" (0.82 mm) | 0.04" (1.07 mm) | 0.07" (1.69 mm) | 0.09" (2.4 mm) | 0.13" (3.25 mm) | 0.17" (4.39 mm) | — |
| 23-5/8" (600 mm) | 1" (25 mm) | 0.03" (0.69 mm) | 0.06" (1.63 mm) | 0.08" (2.12 mm) | 0.13" (3.34 mm) | 0.19" (4.74 mm) | 0.25" (6.42 mm) | — | — |
| 23-5/8" (600 mm) | 1" (25 mm) HD | 0.02" (0.52 mm) | 0.05" (1.22 mm) | 0.06" (1.59 mm) | 0.10" (2.5 mm) | 0.14" (3.56 mm) | 0.19" (4.81 mm) | 0.29" (7.36 mm) | — |
| 29-1/2" (750 mm) | 1" (25 mm) | 0.05" (1.32 mm) | 0.12" (3.08 mm) | 0.16" (3.97 mm) | 0.25" (6.28 mm) | 0.36" (9.22 mm) | — | — | — |
| 29-1/2" (750 mm) | 1" (25 mm) HD | 0.04" (0.99 mm) | 0.09" (2.31 mm) | 0.12" (2.97 mm) | 0.19" (4.71 mm) | 0.27" (6.92 mm) | 0.37" (9.34 mm) | — | — |
| 35-7/16" (900 mm) | 1" (25 mm) | 0.07" (1.87 mm) | 0.18" (4.53 mm) | 0.23" (5.8 mm) | 0.36" (9.24 mm) | — | — | — | — |
| 35-7/16" (900 mm) | 1" (25 mm) HD | 0.06" (1.4 mm) | 0.13" (3.4 mm) | 0.17" (4.35 mm) | 0.27" (6.93 mm) | 0.36" (9.23 mm) | — | — | — |
| 47-1/4" (1200 mm) | 1" (25 mm) | 0.12" (3.09 mm) | 0.31" (7.78 mm) | 0.43" (10.89 mm) | 0.62" (15.8 mm) | — | — | — | — |
| 47-1/4" (1200 mm) | 1" (25 mm) HD | 0.09" (2.32 mm) | 0.23" (5.84 mm) | 0.32" (8.17 mm) | 0.47" (11.85 mm) | — | — | — | — |

_Cells are deflection under static load at ambient temperature, as printed in Strongrate’s 2023 catalog (mm), with inches converted; “—” means no value is printed. Halve the loads for impact or dynamic conditions. Confirm the values for your span in the submittal before final design._

Notes:

- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.

**Uniform load deflection, Strongrate 1" × 6" mesh, 1-1/2" deep (catalog pages 64–65)**

| 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) | — | — | 0.01" (0.37 mm) | 0.02" (0.53 mm) | 0.03" (0.65 mm) | 0.03" (0.76 mm) | 0.04" (1.08 mm) | 5,195 (25,366) |
| 17-3/4" (450 mm) | 0.02" (0.55 mm) | 0.03" (0.75 mm) | 0.06" (1.41 mm) | 0.09" (2.24 mm) | 0.12" (2.97 mm) | 0.14" (3.68 mm) | 0.30" (7.5 mm) | 2,983 (14,563) |
| 23-5/8" (600 mm) | 0.03" (0.76 mm) | 0.04" (0.96 mm) | 0.08" (1.93 mm) | 0.10" (2.56 mm) | 0.15" (3.82 mm) | 0.23" (5.75 mm) | 0.38" (9.58 mm) | 2,502 (12,214) |
| 29-1/2" (750 mm) | 0.07" (1.71 mm) | 0.12" (2.97 mm) | 0.15" (3.85 mm) | 0.23" (5.85 mm) | 0.34" (8.64 mm) | 0.49" (12.43 mm) | — | 2,001 (9,771) |
| 35-7/16" (900 mm) | 0.09" (2.21 mm) | 0.15" (3.78 mm) | 0.27" (6.87 mm) | 0.40" (10.25 mm) | 0.51" (13.06 mm) | — | — | 1,437 (7,017) |
| 47-1/4" (1200 mm) | 0.23" (5.87 mm) | 0.34" (8.69 mm) | 0.61" (15.49 mm) | — | — | — | — | 904 (4,416) |

_Cells are deflection under static load at ambient temperature, as printed in Strongrate’s 2023 catalog (mm), with inches converted; “—” means no value is printed. Halve the loads for impact or dynamic conditions. Confirm the values for your span in the submittal before final design._

Notes:

- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.

**Concentrated point load deflection, Strongrate 1" × 6" mesh, 1-1/2" deep (catalog pages 65–66)**

| 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) | 0.01" (0.28 mm) | 0.03" (0.66 mm) | 0.04" (0.95 mm) | 0.06" (1.44 mm) | 0.08" (2.04 mm) | 0.11" (2.76 mm) | 0.18" (4.53 mm) | — |
| 17-3/4" (450 mm) | 0.02" (0.45 mm) | 0.04" (1.05 mm) | 0.05" (1.37 mm) | 0.08" (2.15 mm) | 0.12" (3.06 mm) | 0.16" (4.14 mm) | 0.22" (5.54 mm) | — |
| 23-5/8" (600 mm) | 0.03" (0.66 mm) | 0.06" (1.55 mm) | 0.08" (2.03 mm) | 0.13" (3.19 mm) | 0.18" (4.53 mm) | 0.24" (6.14 mm) | — | — |
| 29-1/2" (750 mm) | 0.05" (1.26 mm) | 0.12" (2.95 mm) | 0.15" (3.79 mm) | 0.24" (6.01 mm) | 0.35" (8.82 mm) | — | — | — |
| 35-7/16" (900 mm) | 0.07" (1.79 mm) | 0.17" (4.33 mm) | 0.22" (5.55 mm) | 0.35" (8.84 mm) | 0.46" (11.78 mm) | — | — | — |
| 47-1/4" (1200 mm) | 0.12" (2.96 mm) | 0.29" (7.44 mm) | 0.41" (10.41 mm) | 0.59" (15.11 mm) | — | — | — | — |

_Cells are deflection under static load at ambient temperature, as printed in Strongrate’s 2023 catalog (mm), with inches converted; “—” means no value is printed. Halve the loads for impact or dynamic conditions. Confirm the values for your span in the submittal before final design._

Notes:

- Deflections as printed in the factory catalog (2023), static loads at ambient temperature.
- Catalog tables.

## Which resins and surfaces can you order?

The DNV-listed 1" × 6" model is vinyl ester, the resin US suppliers use for harsher chemical service; Strongrate's catalog gives 230°F (110°C) as the maximum temperature of its fire-retardant vinyl ester. The catalog also lists isophthalic, food-grade isophthalic and orthophthalic resin, with concave or gritted tops. Resins are compared on [molded fiberglass grating](https://www.strongrate.us/molded-fiberglass-grating/).

## How is rectangular mesh grating quoted and shipped?

Made in Nantong, China, and shipped from China. Full containers and project quantities are quoted factory-direct; orders under about 500 sq ft, or needed in under 3 weeks, are referred to US stocking importers. Prices are quoted per project: see [fiberglass grating price per square foot](https://www.strongrate.us/pricing/fiberglass-grating-price/), add [hold-down clips](https://www.strongrate.us/accessories/fiberglass-grating-clips/), and [request a quote](https://www.strongrate.us/request-quote/).

## Frequently asked questions

### Why does the DNV certificate list the rectangular model as 25.4×152.4×38?

The certificate gives the model size in millimeters. In 25.4×152.4×38, the first two figures are exactly 1" and 6", the mesh, and 38 mm is the 1-1/2" depth. It is not the 1" × 4" mesh, which is a separate catalog product with no DNV listing.

### Can Strongrate grating replace existing 1" × 4" grating?

Its catalog 1" × 4" mesh at 1" (25 mm) deep is the like-for-like option; the 1" × 6" model is 1-1/2" deep and needs different support heights. Send the existing mesh, depth, panel size and span with your [quote request](https://www.strongrate.us/request-quote/).

### Which way should rectangular mesh run on a walkway?

Structurally, in the span direction the catalog prints for the mesh. On ADA accessible routes, the long dimension of each opening must also be perpendicular to the dominant direction of travel; for small openings, see [mini mesh grating](https://www.strongrate.us/molded-fiberglass-grating/mini-mesh-ada/).

## Related pages
- [Molded fiberglass grating](https://www.strongrate.us/molded-fiberglass-grating/): Molded fiberglass (FRP) grating from Strongrate’s Nantong factory by depth and mesh: square, rectangular and mini meshes, the four DNV-listed models with their ASTM E84 results, panel sizes, resins, surfaces and how to get factory pricing.
- [Mini mesh fiberglass grating](https://www.strongrate.us/molded-fiberglass-grating/mini-mesh-ada/): What mini mesh molded fiberglass grating is, how the ADA 302.3 half-inch opening rule applies to the five mini-mesh patterns in Strongrate’s catalog, their weight, open area, panel sizes and deflection tables, and how to order.
- [1" molded fiberglass grating](https://www.strongrate.us/molded-fiberglass-grating/1-inch-square-mesh/): Specifications, ASTM E84 results, panel sizes and catalog load tables for Strongrate 1-inch-deep molded fiberglass grating with a 1-1/2-inch square mesh (DNV-listed model 38×38×25 mm), and how to order it.
- [2" molded fiberglass grating](https://www.strongrate.us/molded-fiberglass-grating/2-inch-square-mesh/): When to specify 2-inch-deep molded fiberglass grating with a 2-inch square mesh: Strongrate catalog weight, open area, panel sizes and deflection tables, and how to order it.
- [ASTM E84 fire rating](https://www.strongrate.us/resources/astm-e84-class-1-fire-rating/): What ASTM E84 Class 1 (Class A) means for FRP grating, the flame spread and smoke-developed indexes of Strongrate’s six DNV-listed models, and how to specify fire performance.

**Request a quote:** https://www.strongrate.us/request-quote/ · Order a sample: https://www.strongrate.us/samples/ — Send mesh, depth, resin, span, panel size, quantity and ZIP code for rectangular mesh grating. Quotes within 1 business day (US Central time).

## Sources
- Strongrate product catalog “Your Best FRP Solution” (image PDF, Sep 2023), supplied by the site owner (accessed Oct 17, 2026)
- [DNV Type Approval Certificate TAF0000191 Rev. 1, with ASTM E84-19a results and conditions (PDF on Strongrate’s ShipServ supplier profile)](https://www.shipserv.com/Shipserv/pages/profiles/261792/certifications/20241010142426209-DNV-GL-Certificate-GRATINGS-Strongrate.pdf) (accessed Oct 15, 2026)
- [U.S. Access Board, Guide to the ADA Standards, Chapter 3: Floor and Ground Surfaces](https://www.access-board.gov/ada/guides/chapter-3-floor-and-ground-surfaces/) (accessed Oct 15, 2026)

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Fiberglass (FRP) grating made by NANTONG STRONGRATE CO.,LTD in Nantong, China. Products ship from China. Made in Nantong, China · Ships from China · HTS 3925.90.