Flood DefendTM
Durable Customizable Steel Flood Door China Manufacturer & Supplier
Steel flood doors block rising water from entering buildings by sealing the doorway with a rigid steel frame and a pressure-tight gasket. NewFlag manufactures these doors to handle defined water loads and keep a stable seal under pressure.
They protect areas with electrical equipment, pumps, or stored goods that cannot be exposed to moisture. Each door is made to match the exact wall opening, giving it a precise fit and dependable watertight performance during flooding.
Key Features of NewFlag Flood Protection Doors
- Full-height sealing for door openings that require complete flood isolation
- Single-leaf or double-leaf configurations to match different opening widths
- Custom-built sizing based on actual wall openings for accurate on-site installation
- EPDM perimeter seal supporting stable watertight performance under rising flood pressure
- Mild steel or stainless steel door construction paired with fluorocarbon powder coating
- Manual operation with optional automated or remote activation for unattended sites
NewFlag Steel Flood Door Series
Stronger Protection for Critical Rooms
Steel construction with protective coatings resists corrosion in moisture-prone environments, ensuring dependable flood protection for rooms that house essential equipment.
Lower Maintenance for Long-Term Use
Simple mechanical components and durable sealing materials keep service needs low, giving customers a reliable solution that performs across multiple flood seasons.
Automatic Safety for Unattended Locations
Automated activation protects entrances even without on-site personnel, lowering the risk of unexpected water intrusion and giving customers confidence during sudden flood events.
Made-to-Fit Designs for Cleaner Installation
Custom sizing ensures precise alignment with the actual doorway, reducing on-site adjustments and helping contractors complete installation faster and with fewer risks.
Applications of Full-Height Flood Defence Steel Doors
- Underground Parking Entrances
Used at ramp entrances to stop surface water from flooding basement car parks. - Basement Equipment Rooms
Protects pump rooms, boiler rooms, and other low-level mechanical spaces from water intrusion. - Electrical and Generator Rooms
Shields ground-floor and semi-basement power rooms from floodwater that can cause outages. - Metro, Tunnel, and Passage Access Points
Seals entrances to underground tunnels and stops water from spreading through long corridors. - Utility and Cable Tunnels
Blocks water at inspection doors or section gates inside utility corridors. - Waterfront Buildings
Installed on ground-floor entrances of riverside or coastal buildings to resist high water levels. - High-Value Storage Areas
Protects inner warehouse zones or cold storage areas when surrounding spaces are flooded.
Why Choose NewFlag?
NewFlag provides a well-organized portfolio of steel flood door solutions backed by engineering expertise and flexible manufacturing. Every door is designed based on actual doorway dimensions and project conditions, ensuring precise alignment and sealing accuracy.
We support clients through the full process—initial selection, design confirmation, customization, and final manufacturing. OEM cooperation is also available for partners who need consistent product standards across multiple sites.
With NewFlag, customers gain clear product classification, tailored solutions, and support for complex installation requirements. This allows each project to achieve the required flood protection performance with confidence.
What Is a Steel Flood Door?
A steel flood door is a full-height, watertight door designed to block water intrusion during flooding. It functions like a normal industrial door in appearance, but the internal structure is engineered to resist water loads and maintain a complete seal under pressure. These doors are installed in areas where flooding risks are predictable and where equipment, assets, or personnel require protection.
The door panel, frame, gaskets, and locking system work as one sealed assembly. When the door is closed and fully compressed, the system forms a water barrier capable of withstanding static and dynamic pressure generated by rising water.
Key Components of a Steel Flood Door
1. Door Leaf
The door leaf is formed from coated or galvanized steel plates. Internal reinforcement stiffens the panel and distributes water pressure evenly across the surface. A well-designed door leaf prevents bending, deformation, or seal distortion during high-pressure events.
2. Frame Structure
The frame attaches to the surrounding wall and transfers the water load to the building structure. Flood door frames are usually fabricated from heavy-gauge steel profiles or welded frames that offer strong anchoring and minimal deflection.
3. Watertight Gaskets
The gasket system is essential for sealing performance. High-quality EPDM or neoprene gaskets line the perimeter of the door. When the locking system activates, the rubber compresses to fill gaps and prevent leakage.
4. Compression or Multi-Point Locking
Steel flood doors rely on mechanical compression. Handwheel systems, lever handles, or multi-point locks pull the door tightly into the frame. Even pressure around the gasket line ensures consistent sealing.
5. Hardware and Hinges
Heavy-duty hinges support the weight of the door and maintain alignment under pressure. Corrosion-resistant hardware is used in environments with moisture, salt, or chemical exposure.
Performance Requirements and Industry Standards
Hydrostatic Pressure Resistance
The primary performance indicator is the door’s ability to withstand a specified water height. Typical engineered steel flood doors support water levels of 1–6 meters, depending on structural design and usage scenarios.
Leakage Limits
Doors undergo testing to measure allowable leakage. High-quality flood doors keep leakage rates extremely low, ensuring downstream rooms remain dry during an event.
Corrosion Resistance
Galvanized steel, epoxy coatings, or stainless steel upgrades may be required in coastal or chemically active environments.
Fire, Impact, and Structural Integration
Some projects request dual-performance flood doors that also meet fire or impact standards. Integration with the building’s wall structure is critical to avoid weak points around the frame.
Mild Steel vs. Stainless Steel Floor Protection Door
NewFlag’s floor protection door can be made from mild steel or stainless steel, and the right choice depends on the site environment.
Mild steel offers strong structural support at a lower cost, making it suitable for indoor areas, equipment pits, and warehouse floors. It handles heavy loads well but needs coatings to prevent corrosion.
Stainless steel performs better in humid, coastal, or chemical-exposed locations. Its corrosion resistance and stable surface make it ideal for wastewater plants, food facilities, and outdoor applications.
Both materials support safe access, but stainless steel is preferred when long service life and minimal maintenance are required.