Complete Guide to GRP Coating: Applications, Cost, Lifespan & More

GRP (Glass Reinforced Plastic) coating is a vital solution in today’s industrial sector for safeguarding crucial infrastructure against corrosion, chemical damage, and water intrusion. This sophisticated fiberglass coating system delivers exceptional resistance to corrosion and superior waterproofing and durability, significantly prolonging the lifespan of assets.

Particularly in regions with harsh environmental conditions like the UAE, where intense heat and the potential for water contamination are significant concerns, GRP coating has become a preferred method for infrastructure protection.

If you’re wondering what GRP coating is used for, or searching for reliable GRP coating services in UAE and Dubai, this detailed guide will help you make informed decisions.

What is GRP Coating?

GRP coating is an advanced composite material system that incorporates fiberglass matting with polyester resin. This combination results in a reinforced plastic layer that adheres effectively to different substrates, creating an impermeable barrier against moisture, chemicals, and environmental deterioration. 

The application process involves layering several sheets of glass fiber matting, which are infused with specially engineered polyester resin. After curing, this composite coating forms a seamless, jointless surface that removes potential leak points and offers enhanced protection compared to conventional coating methods.

GRP Coating vs GRP Lining: Understanding the Key Differences

GRP lining and GRP coating are similar in that both use Glass Reinforced Plastic (GRP)—a composite of fiberglass and resin—to provide protection against moisture, chemicals, and corrosion. However, they differ significantly in application, thickness, and purpose. GRP coating is typically a thin layer (around 1–2 mm) applied to the external surfaces of structures to protect them from environmental factors like UV radiation, weathering, and abrasion. It acts much like a durable, reinforced paint.

Aspect	GRP Coating	GRP Lining
Definition & Composition	Thin protective layer (2-4mm) applied as liquid resin with chopped strand mat	Thick structural barrier (4-10mm+) using woven roving and multiple layers
Usage Scenarios	Surface protection, minor waterproofing, cosmetic enhancement	Heavy-duty containment, structural reinforcement, severe chemical exposure
Cost Differences	Lower material and labor costs	Higher initial investment but superior long-term value
Typical Applications	Swimming pools, decorative surfaces, light industrial floors	Water tanks, chemical vessels, wastewater treatment facilities

What is GRP Coating Used For?

Common applications include:

• Water Tanks (Overhead, Underground)
  
•  Industrial Floors & Plants
  
•  Swimming Pools & Water Features
  
•  Chemical Storage Areas
  
•  Wastewater Treatment Plants

GRP Coating Benefits: Why Choose This Protection System

• Seamless & Waterproof Protection
  GRP cures into a continuous, joint-free surface that eliminates weak spots where water can seep in. This makes it highly effective for waterproofing roofs, tanks, and other moisture-sensitive areas.
  
• Excellent Chemical Resistance
  GRP coatings resist a wide range of aggressive substances including acids, alkalis, and solvents which makes them ideal for industrial facilities, chemical plants, and wastewater treatment areas where exposure to harsh chemicals is common.
  
• Long Service Life (15–25 Years)
  When properly applied, GRP systems can last up to 25 years with minimal deterioration. This extended lifespan reduces the need for frequent recoating, saving long-term maintenance and replacement costs.
  
• Low Maintenance Requirements
  GRP surfaces are smooth, easy to clean, and resistant to mold or bacterial buildup. 
• Superior Mechanical Strength
  The fiberglass reinforcement within GRP provides excellent impact and abrasion resistance, suitable for high-traffic zones or areas subjected to mechanical stress
• Non-Conductive & Corrosion Resistant
  GRP does not conduct electricity and is immune to rust or electrochemical corrosion.

GRP Coating Specification Standards

Compliance with established standards ensures optimal performance and regulatory approval:

International Standards:

• ISO 9001 quality management systems for manufacturing consistency
• ASMT D2584 for determining resin content and glass fiber percentage
• BS 4994 specifications for tank lining applications in potable water service

UAE-Specific Requirements:

• Dubai Municipality guidelines for water tank coatings in residential and commercial buildings
• DEWA (Dubai Electricity and Water Authority) specifications for water storage systems
• UAE Building Code requirements for protective coatings in harsh environments

Meeting these GRP coating specification standards ensures compliance with local regulations while providing warranty protection and insurance coverage for completed installations.

📚 Reference: UAE Building Code Requirements

GRP Coating Application Process

1. Surface Preparation : Thorough cleaning, degreasing, and profile creation through abrasive blasting or mechanical preparation. Moisture content must be below 4% for optimal adhesion.
2. Primer Application (If Required): Specialized primers may be applied to challenging substrates or when specified by coating system requirements.
3. Base Coat and First Reinforcement: Application of base resin followed by immediate placement of chopped strand mat or woven roving, ensuring complete saturation and air removal.
4. Additional Laminations: Multiple layers applied according to design specifications, with each layer properly consolidated before the next application.
5. Finishing Coat and Quality Control:  Final resin coat applied for smooth finish and UV protection, followed by comprehensive quality testing including adhesion and thickness verification.

This structural waterproofing process requires experienced technicians and controlled environmental conditions to achieve optimal results.

GRP Coating for Water Tanks & Wet Environments 

Water storage applications represent the most demanding test of coating performance. GRP coating for water tanks addresses multiple protection challenges:

• Potable Water Safe

Uses food-grade resins that preserve water quality without adding taste or odor, making it suitable for drinking water storage.

• Leak-Proof Performance

Creates a seamless, joint-free barrier that eliminates leak-prone areas common in tiled or membrane-lined tanks.

• Resists Microbial Growth

The non-porous surface prevents algae, bacteria, and biofilm formation—keeping tanks hygienic with minimal cleaning.

• Strengthens Old Tanks

Reinforces aging concrete or steel tanks while protecting them—prolonging structural life and avoiding costly replacements.

See research: Corrosion Protection Performance Study

GRP Coating Chemical Resistance & Lifespan

GRP coating chemical resistance varies by resin type and environmental conditions:

• Acid Resistant

  Vinyl ester and novolac resins withstand strong acids like sulfuric and hydrochloric—ideal for industrial use.

• Handles Alkaline Conditions

Polyester-based GRP coatings resist mild to strong alkaline substances, with advanced options for harsh environments.

• Solvent Compatibility

Custom resin selection ensures stability in tanks exposed to solvents or organic chemicals.

• Long Lifespan (15–30 Years)

With correct application and basic maintenance, GRP coatings offer 15–25 years of protection—sometimes lasting over 30 years.

Common GRP Coating Failure Causes & Prevention

1. Improper Surface Preparation

Cause: Poor cleaning or surface profiling
Result: Coating peels or delaminates
Prevention: Follow strict prep procedures and quality checks

2. Incorrect Resin Mixing

Cause: Wrong catalyst ratio or uneven mixing
Result: Incomplete curing, soft or brittle areas
Prevention: Use trained applicators and accurate mixing controls

3. Environmental Contamination

Cause: High humidity, dust, or extreme temperatures during application
Result: Weak bonding and surface defects
Prevention: Apply in controlled, clean environments

4. UV Exposure Damage

Cause: No or poor UV topcoat
Result: Fading, chalking, or surface breakdown
Prevention: Apply a UV-resistant topcoat and maintain it regularly

GRP Coating Inspection Methods

Routine checks include:

•  Visual Inspection
•  Hammer Testing for Voids
•  Ultrasonic Thickness Measurement
•  Adhesion Strength Pull-off Testing
• Shore hardness testing for proper cure verification
• Impact resistance evaluation

GRP Coating Repair Techniques

Minor Repair Procedures:

• Surface preparation: Sanding and cleaning of damaged area
• Resin patching: Application of matching resin system
• Reinforcement addition: Fiberglass mat for structural repairs
• Finishing: Blending with existing surface texture

Major Repair Requirements:

• Damage assessment: Determining extent of delamination or failure
• Section removal: Cutting out damaged areas to sound material
• Complete re-application: Full system reconstruction in repair area
• System integration: Proper bonding with existing coating

Installation Cost of GRP Coating in UAE

1. Surface Area Impact

• Small Projects (<100m²): Higher cost per m² due to setup and mobilization.
  
• Medium Projects (100–1000m²): Most cost-efficient range.
  
• Large Projects (>1000m²): Lower rates due to economies of scale.
  

2. Material Thickness & Pricing

• Standard Coating (2–3mm): AED 80–120/m²
  
• Heavy-Duty (4–6mm): AED 150–250/m²
  
• Structural Lining (6mm+): AED 200–400/m²
  

3. UAE Labor Market Factors

• Skilled labor availability can affect scheduling and costs
  
• Prices vary with seasonal demand and project urgency
  
• Certified applicators and safety protocols may add to cost
  

4. Industry-Specific Pricing

• Water Tanks: AED 100–180/m² (includes health authority compliance)
  
• Chemical Areas: AED 200–350/m² (special resins required)
  
• Marine Use: AED 150–280/m² (UV-resistant topcoat included)
  
• Industrial Floors: AED 120–220/m² (includes anti-slip finish)
  

5. Additional Cost Factors

• Surface Prep: Adds 20–30% to total cost
  
• Access Needs: Scaffolding, confined space gear, etc.
  
• Environmental Controls: For temperature and humidity regulation
  
• Testing & Certification: Third-party inspections may be required

GRP Coating Maintenance Requirements

•  Clean with mild detergents
  
•  Inspect annually
  
• Patch recoat minor damage
  
•  Ensure fire-resistant topcoat where required
  

 Consistent care ensures full 20–25 year lifespan.

Industries Using GRP Coating

Water Treatment Industry:

• Municipal water plants for tank and pipeline protection
• Desalination facilities requiring saltwater corrosion resistance
• Swimming pool complexes needing hygienic, attractive surfaces
• Wastewater treatment plants handling aggressive biological and chemical environments

Oil & Gas Sector:

• Offshore platforms requiring marine environment protection
• Refineries needing chemical and fire resistance
• Storage terminals for product containment and safety
• Pipeline facilities requiring long-term corrosion protection

Food Processing Industry:

• Beverage production requiring taste and odor neutrality
• Dairy processing needing hygienic, easy-to-clean surfaces
• Meat processing requiring chemical resistance and cleanability
• Bakery operations needing food-safe, durable flooring

Marine & Coastal Infrastructure:

• Port facilities exposed to saltwater and chemical cargo
• Coastal buildings requiring weather and corrosion resistance
• Marine vessels needing lightweight, durable protection
• Offshore structures requiring extreme environment performance

Hospitality & Health Facilities:

• Hotel water systems requiring aesthetic and functional performance
• Hospital facilities needing sterile, easy-to-maintain surfaces
• Spa and wellness centers requiring luxury appearance with durability
• Sports facilities needing slip-resistant, attractive surfaces

Why Choose GRP Coating Over Alternatives?

Coating Type	Chemical Resistance	Durability	Cost
GRP Coating	High	Long	Less
Epoxy Coating	Moderate	Medium	More
PU Coating	Moderate	Short	Less

  GRP delivers superior long-term performance for a better ROI.

Key Factors When Choosing a GRP Contractor

• Proven experience in similar environments (water, industrial, marine)
  
• Certified and well-trained application teams
  
• Strong quality control and testing procedures
  
• Compliance with UAE regulations and health/safety standards
  
• Positive project history with reliable client references
  

Conclusion

GRP coating is not just a protective barrier—it’s a long-term investment in structural safety, hygiene, and environmental compliance. From water tanks to chemical-resistant flooring, its benefits are unmatched by conventional coatings.

Whether you’re managing a villa in Dubai or an industrial site in Sharjah, GRP coating delivers reliability, compliance, and peace of mind.

Ready to protect your assets with GRP?

Request a free consultation today to discuss your specific coating requirements.