Skip to content
Strongrate Fiberglass Grating · Factory-Direct, home

Product overview

Fiberglass Grating (FRP Grating)

Updated

Fiberglass grating, or FRP (fiber-reinforced plastic) grating, is non-conductive floor grating made in two main types: molded panels, typically about 30–35% glass, and pultruded bar grating, typically about 65–70% glass. Choose molded for trench covers, chemical plants and two-way strength; choose pultruded for longer spans. Strongrate makes both in Nantong, China.

What is FRP grating?

FRP stands for fiber-reinforced plastic, often written fiberglass-reinforced plastic: glass-fiber reinforcement set in a thermoset resin such as isophthalic polyester, vinyl ester or phenolic. The same product is sold as fiberglass grating, FRP grating, composite grating or fiberglass floor grating; in the UK it is called GRP (glass-reinforced plastic) grating.

Fiberglass grating is non-conductive, and US makers describe it as up to 70–75% lighter than steel grating. How it compares on cost and service life: fiberglass vs steel grating.

Molded or pultruded: which fiberglass grating do you need?

Molded grating is cast as one piece with strength in both directions and is the usual choice for trench covers, general flooring and chemical plants. Pultruded grating is built from bearing bars joined by cross rods, is marketed as about twice as stiff, and suits platforms, mezzanines and walkways with longer spans. Compare load tables at your actual span before deciding.

Molded vs pultruded fiberglass grating: values US makers publish
AttributeMolded fiberglass gratingPultruded fiberglass grating
How it is madeOne-piece panel cast in a mold; strength in both directionsPultruded bearing bars joined by cross rods, commonly 6" (152 mm) on center
Glass content by weightabout 30–35%1about 65–70%1
StiffnessBaselineMarketed as about 2× stiffer than molded2
Common depths1" (25 mm), 1-1/2" (38 mm) and 2" (51 mm)1" (25 mm) and 1-1/2" (38 mm) I-bar; 2" (51 mm) T-bar
Open areaabout 70% (1-1/2" square mesh)3I-bar about 40% or 60%; T-bar about 33% or 50%4
Weight at 1-1/2" (38 mm) deep (lb/ft²)3.75–3.94 lb/ft² (18.3–19.2 kg/m²)32.8–3.0 lb/ft² (13.7–14.6 kg/m²), 60%-open I-bar3
Slip-resistant surfaceConcave (meniscus) top or applied quartz gritBonded grit
Typical usesTrench covers, general flooring, chemical plantsPlatforms, mezzanines, bridge walkways
Strongrate glass content (catalog)30–35% by weight60–65%
Strongrate range (catalog)19 meshes, 1/2" (13 mm) to 2-9/16" (65 mm) deep, 1.2–10.7 lb/ft² (5.8–52.0 kg/m²)536 types, 1" (25 mm) to 3" (76 mm) deep, 1.7–15.1 lb/ft² (8.5–73.6 kg/m²)5
Industry rows compiled Oct 2026 from US makers. Strongrate rows are values from its 2023 catalog, confirmed in your quote and submittal drawings before design use. Every Strongrate mesh and type with its weight and open area: fiberglass grating sizes, weight and open area. The full comparison is on molded vs pultruded fiberglass grating.

Notes

  1. 1Typical published figure, not Strongrate data.
  2. 2A marketing comparison; compare actual load tables.
  3. 3Typical published figures from US makers, not Strongrate data.
  4. 4Typical published options from US makers, not Strongrate data.
  5. 5Values as printed in the factory catalog (2023).
Molded fiberglass grating, plan viewA square mesh of bars running in both directions, molded as one piece, with square openings between the bars.PlanMesh openingBars run bothways, moldedas one pieceMolded fiberglass grating, sectionSection through three molded bars, showing the top walking surface, the bar depth and the mesh spacing between bar centers.SectionMesh spacingTop surfaceDepth
Molded fiberglass grating: a one-piece square-mesh panel with bars in both directionsSchematic — not to scale
Pultruded I-bar fiberglass grating, sectionSection through four parallel I-shaped load bars joined by a cross rod, showing bar spacing center to center, the depth and the openings between bars.Section across the load barsBar spacingcenter to centerI-bar (load bar)DepthOpeningCross rodPultruded I-bar fiberglass grating, plan viewPlan strip showing parallel load bars held at a fixed spacing by cross rods that run across them.PlanLoad barsCross rods
Pultruded fiberglass grating: I-shaped bearing bars tied together by cross rodsSchematic — not to scale
  • Product familyMolded fiberglass gratingMolded fiberglass (FRP) grating by depth and mesh, with panel sizes, resins and the DNV-listed models.
  • Product familyPultruded fiberglass gratingPultruded fiberglass (FRP) I-bar and T-bar grating by depth and open area, with span guidance.

What sizes do fiberglass grating panels come in?

Molded fiberglass grating panels come in four common US sizes, plus 4 ft × 6 ft (1220 × 1830 mm) for heavy-duty panels. Pultruded panels are commonly 3, 4 or 5 ft (915, 1220 or 1525 mm) wide and up to 20 ft (6.10 m) long. Strongrate’s 2023 catalog lists three of the four molded sizes, plus 5 ft × 13.12 ft (1524 × 4000 mm), and pultruded panels up to 5 ft × 20 ft (1524 × 6100 mm).

Common US fiberglass grating panel sizes (molded) and the sizes in Strongrate’s catalog
Panel size, ft (mm)Area (sq ft)Typical useStrongrate catalog (printed size)
3 ft × 10 ft (915 × 3050 mm)30Standard molded panelListed as 3 ft × 10 ft (921 × 3050 mm) for 8 meshes (square, mini, rectangular)1
4 ft × 8 ft (1220 × 2440 mm)32Standard molded panelListed as 4 ft × 8 ft (1220 × 2440 mm) for 4 meshes (square, mini)1
4 ft × 12 ft (1220 × 3660 mm)48Standard molded panelListed as 4 ft × 12 ft (1220 × 3660 mm) for 11 meshes (square, mini, rectangular)1
5 ft × 10 ft (1525 × 3050 mm)50Standard molded panelNot listed; the catalog’s 5 ft molded panel is 5 ft × 13.12 ft (1524 × 4000 mm)1
4 ft × 6 ft (1220 × 1830 mm)24Heavy-duty molded panelListed as 4 ft × 6 ft (1220 × 1830 mm) for 1 mesh (rectangular)1
The first three columns are US industry norms from makers’ catalogs, with metric sizes rounded to the nearest 5 mm; the last column gives the size as printed in Strongrate’s 2023 catalog. Weights, depths and open area by size: fiberglass grating sizes, weight and open area.

Notes

  1. 1Values as printed in the factory catalog (2023); confirmed in your quote and submittal drawings.

Which Strongrate fiberglass grating models are DNV type-approved?

Six Strongrate models are listed on DNV Type Approval TAF0000191 Rev. 1: 1" (25 mm) deep, 1-1/4" (32 mm) deep and 1-1/2" (38 mm) deep molded square mesh, a rectangular-mesh molded model, and the I 6015 I-bar and T5020 T-bar pultruded models. Their ASTM E84-19a flame spread indexes run from 5 to 20. The certificate covers fire properties, not structural strength; see certifications and test reports.

Which fiberglass grating options does Strongrate list?

Beyond the six DNV type-approved models, Strongrate’s 2023 product catalog and its websites list the options below. Send the option, size and quantity with your quote request.

Strongrate fiberglass grating options
OptionWhat Strongrate lists
Molded mesh4 square and 10 rectangular meshes, 1/2" (13 mm) to 2-9/16" (65 mm) deep (catalog)1
Mini mesh5 mini meshes with openings from 1/2" (13 mm) to 1" (26 mm) (catalog)1
Gritted topGritted top on molded and pultruded grating; slip coefficient 0.91 for the normal grit, citing ASTM D2047 (catalog)2
Concave topConcave (meniscus) top on molded grating (catalog)
Cross-groove topCross-groove molded grating (website listing)
Covered (solid top)Solid covers with a checker or grit finish, molded and pultruded (catalog)
Heavy-duty molded1-1/2" × 1-1/2" (38 × 38 mm) heavy duty, 2" (50 mm) to 2-9/16" (65 mm) deep, and the 1" × 2" (25 × 51 mm) mesh (catalog)1,3
High-load pultrudedHI and HL I-bar series: 13 types, 1" (25 mm) to 3" (76 mm) deep, 40–60% open; the catalog gives HI spans under AASHTO truck, car and forklift wheel loads1
Pultruded T-barT-bar series: 10 types, 1" (25 mm) to 2" (50 mm) deep, 12–50% open (catalog; T5020 is on the DNV certificate)1,4
Pultruded I-barI-bar and SI series: 13 types, 1" (25 mm) to 1-1/2" (38 mm) deep, 40–83% open (catalog; I 6015 is on the DNV certificate)1,4
ResinsVinyl ester, isophthalic polyester, food-grade isophthalic, and orthophthalic polyester (molded only), all fire retardant (catalog)5
Stair treads and tread coversMolded tread covers and one-piece tread panels, pultruded grating treads, and stair nosing covers (catalog)1
ClipsSix clip types (L, M, C, W, J and G), mainly stainless steel (catalog)6
Catalog entries are as printed in Strongrate’s 2023 product catalog; website entries are product titles on strongrate.com and strongrate.cn. Values are confirmed in your quote and submittal drawings.

Notes

  1. 1Values as printed in the factory catalog (2023).
  2. 2Catalog value.
  3. 3Deflections as printed in the factory catalog (2023), static loads at ambient temperature; confirm for your span in the submittal before final design.
  4. 4Bar depth and open area are not stated on the certificate.
  5. 5Maximum service temperatures as printed in the catalog’s resin table; its chemical-resistance chart prints lower maximums.
  6. 6The catalog’s Chinese text also lists galvanized steel; the clip material is stated in your quote.
  • ProductFiberglass stair tread coversGritted covers that retrofit worn or slippery steps without replacing the stair.
  • AccessoryFiberglass grating clipsHold-down clips by type, the spacing rules in guide specifications, and clips per panel.
  • Molded and pultrudedFiberglass stair treadsMolded and pultruded fiberglass stair treads from Strongrate’s catalog, with OSHA 1910.25 stair rules and design loads.

Where is fiberglass grating used?

A US distributor’s guide recommends molded grating for trench covers, general flooring and chemical plants, and pultruded grating for platforms, mezzanines and bridge walkways. Because it is non-conductive, fiberglass grating is also marketed for electrical flooring.

How much do fiberglass grating panels cost?

Strongrate quotes per project in USD, with the Incoterm and quote date stated. For context, published vendor price guides put molded grating at about $12–$18 per sq ft and pultruded at about $20–$28 per sq ft, and US stocking distributors’ published prices for full-size molded panels, 1-1/2" and 2" deep with square mesh, run from about $9 to $17 per sq ft (Oct 2026). These are other sellers’ prices, not Strongrate prices. See fiberglass grating price per square foot and FRP grating landed cost, duty and freight.

Frequently asked questions

How do I choose the depth of fiberglass grating?

Choose the depth from a load table at your clear span and design load, not from the panel size. Common US molded depths are 1" (25 mm), 1-1/2" (38 mm) and 2" (51 mm). Makers’ published safe loads rest on safety factors from 2:1 to 5:1, so compare tables on the same basis. How to read them: fiberglass grating load tables.

What colors does fiberglass grating come in?

Standard US colors are yellow, dark gray, light gray and green, and orange commonly signals vinyl ester resin. Ask for the colors available in your resin with your quote.

Which resin should I choose for fiberglass grating?

Isophthalic polyester suits general industrial use, vinyl ester harsher chemical service, and phenolic marine and offshore work. Strongrate’s catalog lists fire-retardant vinyl ester, isophthalic, food-grade isophthalic and orthophthalic resins, with a chemical-resistance chart on the fiberglass grating specifications page; send your chemicals, concentrations and temperatures with your quote request.

Request a quote

Get a quote by panel size: send the type, depth, mesh, panel size, resin, quantity and destination ZIP or postal code. Quotes within 1 business day (US Central time).

Request a quoteOrder a sample
Sources
  1. DNV Type Approval Certificate TAF0000191 Rev. 1 (ASTM E84-19a results) (accessed Oct 15, 2026)
  2. strongrate.com product listings (page titles) (accessed Oct 15, 2026)
  3. strongrate.cn product listings (page titles) (accessed Oct 15, 2026)
  4. Strongrate product catalog “Your Best FRP Solution” (image PDF, Sep 2023), supplied by the site owner (accessed Oct 17, 2026)
  5. Fibergrate FAQ (accessed Oct 15, 2026)
  6. Fibergrate pultruded grating page (accessed Oct 15, 2026)
  7. Fibergrate molded FRP products brochure (accessed Oct 15, 2026)
  8. Fibergrate, Molded FRP Grating Details and Options (accessed Oct 15, 2026)
  9. McNichols molded fiberglass grating catalog (accessed Oct 15, 2026)
  10. Grating Pacific, molded fiberglass grating page (accessed Oct 15, 2026)
  11. Direct Metals, product applications (accessed Oct 15, 2026)
  12. Grating Pacific, Pultruded Sizes and Options (accessed Oct 15, 2026)
  13. Strongwell grating page (DURADEK) (accessed Oct 15, 2026)
  14. Direct Metals blog, Pultruded vs molded fiberglass grating (Jan 15, 2026) (accessed Oct 15, 2026)
  15. American Grating Resin Selection Guide (accessed Oct 15, 2026)
  16. Fibergrate FRP benefits page (accessed Oct 15, 2026)
  17. FRP vendor price guides (GTO FRP 2025 guide; Income Pultrusion guide, undated) (accessed Oct 15, 2026)