Waterproofing failures can significantly affect the durability and service life of concrete structures. Cracks, leakage, moisture penetration, and chemical exposure can lead to concrete deterioration, corrosion of reinforcement, and costly maintenance requirements. Modern construction projects require waterproofing solutions that provide strong adhesion, flexibility, chemical resistance, and long-term protection.
The Fosroc Nitoproof 900PU is a highly elastic, 100% solids, two-component spray-applied polyurethane coating developed to address demanding waterproofing requirements. With rapid curing, seamless application, and high mechanical strength, the coating provides durable protection for structures exposed to water, chemicals, abrasion, and environmental conditions.
Challenges in Conventional Waterproofing Systems
Traditional waterproofing methods often face limitations when exposed to modern construction requirements. Common challenges include:
- Poor adhesion with different substrates
- Cracking due to structural movement
- Extended curing periods affecting project schedules
- Reduced resistance against chemicals and contaminants
- Joint-related failures leading to water ingress
- High repair and maintenance costs after waterproofing failure
Selecting the right waterproofing coating is essential to ensure effective sealing, structural protection, and extended service life.
Introduction to Fosroc Nitoproof 900PU
Fosroc Nitoproof 900PU is a two-component polyurethane waterproofing coating applied using plural-component spray equipment. The material forms a seamless and flexible membrane that protects structures from water penetration and environmental deterioration.
The coating provides:
- Rapid curing performance
- High elasticity for crack movement accommodation
- Strong bonding with multiple substrates
- Resistance against chemicals, abrasion, and UV exposure
- Seamless waterproofing without joints or weak points
The solution is suitable for demanding applications including roofs, podiums, basements, green roofs, water-retaining structures, and infrastructure projects.
Key Advantages of Nitoproof 900PU
Resistant to Harsh Conditions
Nitoproof 900PU withstands exposure to:
- Abrasion
- Chemicals
- Subsoil contaminants
- UV radiation
- Moisture and water pressure
Multi-Substrate Compatibility
The coating provides adhesion on various surfaces including:
- Concrete
- Wood
- Metal
- Tiles
Rapid Curing
The rapid curing technology enables:
- Foot traffic within approximately 10 minutes
- Full serviceability within 48 hours
High Mechanical Strength
With tensile strength exceeding 18 MPa, Nitoproof 900PU provides enhanced durability compared to conventional coating solutions.
Dynamic Crack Bridging Capability
The elastic membrane can accommodate cracks up to 3.2 mm, reducing the risk of leakage caused by structural movement.
Seamless Waterproofing Protection
The monolithic membrane eliminates:
- Joints
- Weak points
- Water leakage paths
Root Penetration Resistance
The coating is suitable for:
- Green roofs
- Planter boxes
- Podium gardens
100% Solids and VOC-Free
The formulation provides:
- No solvent emissions
- Improved applicator safety
- Environment-friendly application
Fosroc Nitoproof 900PU Application Process
Proper application is essential to achieve maximum waterproofing performance. The process includes equipment preparation, substrate treatment, primer application, and spray coating.
Equipment Requirements
Personal Protective Equipment (PPE)
Required safety equipment includes:
- Protective overalls
- Chemical-resistant gloves
- Safety goggles
- Face mask or respirator
- Safety shoes
Surface Preparation Equipment
The following tools are used for substrate preparation:
- Electric or pneumatic grinder
- Vacuum cleaner
- Wire brush
- Air blower or compressed air system
- Cleaning tools
Application Equipment
The Nitoproof 900PU application requires:
- Dual-component spray equipment
- Plural-component proportioning machine
- Air purge or mechanical purge spray gun
- Heated hoses for material circulation
- Spray accessories
The material temperature should be maintained between +50°C to +70°C during application.
Surface Preparation Before Application
Proper surface preparation ensures strong bonding and long-term coating performance.
Structural Soundness
The substrate should be:
- Structurally sound
- Free from loose particles
- Free from laitance
- Free from contaminants
- Free from sharp projections
Mechanical Preparation
Heavy-duty grinding is required to:
- Remove surface laitance
- Eliminate weak concrete layers
- Improve surface profile
- Enhance primer adhesion
Substrate Conditions
Recommended conditions include:
- Minimum concrete grade: M20
- Surface moisture content: Less than 5%
- Relative humidity: Below 75%
Application of Nitoprime 31 Primer
The primer application prepares the substrate for effective bonding with Nitoproof 900PU.
Primer Application Procedure
- Mix the entire contents of base and hardener using a low-speed mechanical mixer.
- Do not part-mix components.
- Apply primer uniformly at approximately 0.25–0.30 kg/m², depending on surface porosity.
- Apply a second primer coat if excessive absorption occurs.
- Broadcast fire-dried sand of 0.2–0.5 mm grain size while the primer remains wet.
- Allow the primer to become touch-dry before applying polyurethane coating.
- If PU application is delayed beyond 24 hours, apply a fresh primer coat.
Application of Nitoproof 900PU
Material Preparation
Before spraying:
- Ensure components are properly circulated.
- Maintain material temperature between +60°C to +70°C.
- Check equipment settings for consistent application.
Spray Application
The coating is applied using plural-component spray equipment to achieve:
- Uniform thickness
- Seamless coverage
- Consistent membrane formation
Vertical Termination Details
For effective waterproofing continuity:
- Extend Nitoproof 900PU approximately 300 mm onto vertical surfaces.
- Create a 6 mm × 6 mm groove at termination points.
- Ensure proper polyurethane penetration into the groove.
Application Methodology for Nitoproof 900PU Waterproofing System
The system includes detailed waterproofing treatments for:
- Horizontal termination areas
- Vertical termination points
- Corners and joints
- Expansion joints and upstand details
These detailing methods help maintain waterproofing continuity and prevent leakage at vulnerable locations.
Application Areas
Fosroc Nitoproof 900PU is suitable for:
- Roof waterproofing
- Podium decks
- Basements
- Parking areas
- Green roofs
- Planter boxes
- Water-retaining structures
- Industrial facilities
- Infrastructure projects
- Underground structures
Benefits for Construction Professionals
Applicators
- Rapid application process
- Efficient site execution
- Reduced downtime
- Seamless coating application
Contractors and Builders
- Reduced repair requirements
- Faster project completion
- Long-term waterproofing performance
- Lower maintenance needs
Architects and Consultants
- Suitable for waterproofing specifications
- Flexible application options
- Reliable performance across project types
Civil Engineers
- High-performance polyurethane technology
- Crack-bridging capability
- Suitable for demanding environments
Modern structures require waterproofing solutions capable of handling movement, moisture exposure, chemical attack, and demanding site conditions. Fosroc Nitoproof 900PU combines rapid curing polyurethane technology with seamless membrane protection to provide reliable waterproofing for a wide range of construction applications.
With high elasticity, strong adhesion, chemical resistance, and fast application, Nitoproof 900PU supports durable protection for buildings, infrastructure projects, and industrial facilities where long-term waterproofing performance is required.
Fosroc Chemicals (India) Private Limited
Address: Embassy Point No.150, 2nd Floor, Infantry Road, Bangalore – 560001
Tel: +91 80 4252 1900 | Fax: +91 80 2228 1510
Email: enquiry.india@fosroc.com | Website: www.fosroc.com
