Introduction

In modern industrial, marine, and infrastructure settings, FRP (Fiberglass Reinforced Plastic) grating has surged in popularity as a high-performance alternative to traditional materials like steel or aluminum. Its outstanding characteristics—lightweight, non-corrosive, non-conductive, and low maintenance—make it an increasingly common choice for platforms, walkways, stairs, drainage covers, and more.

That said, not all FRP gratings are made the same. Choosing the right type hinges on understanding the differences in manufacturing methods, materials, load-bearing capacity, environmental resistance, surface design, and special-use variations. In this deep dive, we explore the key types of FRP gratings and how to choose the perfect fit for your application.

1. Molded FRP Grating

Manufacturing & Characteristics

Produced via molding: Continuous glass fiber rovings placed in a heated mold are saturated with resin. The resulting panels deliver bi-directional strength and even load distribution.

High impact resistance: Excellent tolerance for dynamic forces.

Cutout flexibility: Cutouts for pipes/equipment don’t seriously weaken structural integrity.

Advantages

Exceptional chemical and corrosion resistance, ideal for harsh environments.

Slip-resistant textures (e.g., grit surfaces, meniscus profiles) enhance safety on walkways.

Best for small spans requiring multi-directional load handling—think platforms, stairs, and walkways in chemical plants, wastewater treatment facilities, and food-processing zones.

2. Pultruded FRP Grating

Manufacturing & Characteristics

Created by pulling continuous fiberglass strands through a resin bath and heated die, then assembled with cross bars and epoxy.

Yields unidirectional strength—stronger along the direction of fiber alignment—and supports longer spans.

Advantages

Higher load capacity and deeper span capabilities than molded grating.

Highly consistent in quality and dimensions due to continuous production processes.

Best for heavy-duty, long-span applications like bridges, vehicle ramps, infrastructure platforms, and large industrial structures.

3. Open Mesh vs Covered Grating & FRP Plate

Open Mesh Grating

Features grid-like openings that allow drainage and ventilation. It’s lightweight and easy to install—especially suitable for outdoor or washdown environments.

Covered Grating

Adds a slip-resistant solid top, providing a continuous surface ideal for cart use and hiding debris below.

It increases stiffness (~30%) and load capacity.

Especially useful in environments needing smooth surfaces—e.g., food processing plants, labs, warehouses.

FRP Plate

A solid FRP sheet, non-porous and easy to clean—excellent for areas that can’t afford fluid or debris penetration (e.g., clean rooms, hygienic zones).

Use open mesh for drainage, ventilation, and lighter-weight needs. Choose covered grating or solid plates where slip protection, surface hygiene, or containment is paramount.

4. Resin System Types: Polyester, Vinyl Ester, Phenolic & Specialty

Polyester (Standard)

Balance of cost and performance. Good for general applications with modest chemical exposure (weak acids/alkalis).

Vinyl Ester

Enhanced corrosion resistance, especially in aggressive chemical and high-temperature environments.

Phenolic

Outstanding fire, smoke, and toxicity resistance, often used in emergency egress or fire-sensitive zones.

Specialty Resins

Food-grade, conductive, translucent, or high fire-rated options exist depending on application needs.

5. Mesh Size & Surface Texture Options

Mesh Sizes

Small (e.g., 19×19 mm): High slip resistance, safe for stairs or public pathways.

Medium (~38×38 mm): Versatile general use.

Large (≈50×50 mm): Excellent for drainage but may risk dropped tool hazards.

Surface Finishes

Plain: Suitable in dry, clean indoor spaces.

Gritted or Grooved: For slippery or wet areas.

Color & UV Coatings: Yellow or gray are common; topcoats provide UV resistance or branding flexibility.

6. Sustainability & Compliance

FRP grating offers a low carbon footprint, longevity, and minimal maintenance compared with steel.

Some modern variants are fully recyclable, aiding sustainable facility development.

Meets industry standards like ASTM E84 (fire), BS 4592-6:2008 (industrial flooring), BS EN ISO 14122-3:2016, ADA, and others.

Choosing the Right Type: A Quick Guide
Application Criteria Recommended Type
Multi-directional load, chemical exposure Molded FRP
Long spans or heavy loads Pultruded FRP
Drainage & ventilation Open mesh grating
Solid walking surface or containment Covered grating or FRP plate
Budget general use Polyester resin
Chemical resistance Vinyl ester resin
Fire-sensitive areas Phenolic resin
Slip-prone conditions Gritted or grooved surface
Compliance & low environmental impact UV-coated, recyclable options
Conclusion

FRP grating stands out as a versatile, durable, and safer alternative to traditional grating materials. Whether your project involves corrosive chemical plants, marine docks, pedestrian walkways, or industrial platforms, your choice of FRP type—from molded or pultruded to resin system and surface style—matters. To know more details, read this :https://accessindustrial.com/en/Product/fiberglass-grating/

Use molded FRP for bi-directional strength in heavy chemical exposure.

Use pultruded FRP when span and load demands are high.

Pair with open mesh for drainage or choose solid surfaces for cleanliness and safety.

Match your resin to the exposure conditions—polyester for cost-efficiency, vinyl ester for harsh environments, phenolic for fire zones.

Always factor in standards, sustainability, and surface safety.

Frequently Asked Questions (FAQ)

1. What is the main difference between molded and pultruded FRP grating?
Molded FRP offers bi-directional strength and high impact resistance, while pultruded FRP provides high strength along the fiber direction and supports longer spans.

2. Which resin type is best for chemical exposure?
Vinyl ester resin offers superior chemical resistance compared to standard polyester; phenolic resin adds fire and smoke resistance if needed.

3. Should I choose open mesh or covered grating?
Open mesh is ideal for environments requiring drainage and airflow. Covered grating or FRP plate is better when you need a solid surface for carts, hygiene, or to block debris.

4. How do mesh size and surface texture affect usability?
Smaller mesh prevents falling objects and improves slip safety. Gritted or grooved textures add traction in wet or oily settings, while plain surfaces work in cleaner conditions.

5. Can FRP grating meet fire safety standards?
Yes—phenolic resins are engineered for fire-sensitive areas, and many FRP products meet ASTM E84 and other fire safety standards.

6. Is FRP grating eco-friendly?
FRP grating can be fully recyclable and boasts a lower carbon footprint plus extended lifespan versus steel alternatives.

7. How do I determine the right size and thickness?
Match panel thickness and span to expected loads:

≤1 m span: 25–30 mm

1–1.5 m: 30–38 mm

1.5–2 m: 38–50 mm

2 m: reinforced panels or added supports