Flap Valves – High-Performance Non-Return Solutions
At AQUIKO, we supply a comprehensive range of high-quality flap valves engineered for robust flood-defence, drainage and sewer applications. Designed to prevent reverse flow and ensure reliable operation, our flap valves deliver dependability in demanding UK environments. Whether you need wall-mounted, pipe-mounted, side-hung or bespoke units, you’ll find the right solution here.
Why Choose AQUIKO Flap Valves
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Proven reverse-flow prevention — our flap valves are designed to close quickly and effectively under back-pressure, reducing flood risk and protecting infrastructure.
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Corrosion-resistant materials — using marine-grade finishes and precision fabrication, we deliver valves that perform in harsh conditions and stand the test of time.
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Minimal maintenance — large opening angles and flush design components ensure debris is less likely to cause jams, giving you lower lifetime costs.
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UK-focussed availability — with AQUIKO as part of Aquatic Control Engineering, we stock standard sizes and custom options right here in the UK, supporting fast delivery and local service.
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Bespoke capability — if your project demands unusual dimensions, unique mounting or specific materials (e.g., stainless steel 316), our custom flap valve service has you covered.
Our Flap Valve Product Range
Browse by configuration:
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Wall-Mounted Flap Valve — ideal for mounting on outfalls, culverts or headwalls where a standard plate solution fits easily.
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Pipe-Mounted Flap Valve — designed for insertion into pipes, enabling end of line non-return protection for drainage or sewer systems.
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Side-Hung Door Flap Valve — perfect for providing a fish friendly solution to flood defence.
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Square Flap Valve & Custom Variants — for bespoke projects, larger openings or special materials requirements.
Installation & Service Considerations
When specifying a flap valve, please consider:
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Minimum required opening angle – ensuring full flush out of debris and achieving the fastest response on closure (studies show larger opening angles reduce head-loss and improve performance).
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Material choice – if your installation is coastal or in chemically-aggressive environment, ask us about stainless steel 316 options for enhanced corrosion resistance.
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Finish, flange type and access requirements – integration with your headwall or pipework should be seamless; our team will advise on custom modifications and site-fit details.
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Maintenance access – our designs require minimal maintenance.
Why AQUIKO & Aquatic Control Engineering
As part of Aquatic Control Engineering, AQUIKO benefits from decades of experience in flood-defence systems, fish-passage friendly design and robust hydraulic engineering. That means your flap valve isn’t an off-the-shelf item alone, but part of a broader system supported by engineering, service and UK logistics.
Ready to specify your flap valve? Get in touch with our sales team today for:
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Stock availability and lead-times
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Bespoke sizing and materials
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Support with specification, drawings and installation advice
01777 819 734 | info@aquiko.co.uk
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Our pipe mounted flap valve range has a compact design. The compact design enables the product is lightweight and easy to install. Made from HDPE which is an extremely robust material and shock absorbent. Therefore, a great choice for flap valves where they are prone to being hit by debris. The lightweight design also ensures a much lower head loss when compared to cast iron or stainless-steel alternatives. HDPE also has a low carbon footprint. -
Side Hung Doors are a simple solution, providing a fish friendly solution to flood defence. Our design delivers a strong product that is virtually maintenance free. Each AQUIKO Side Hung Door set is built to suit the exacting requirements of each enquiry. The AQUIKO Side Hung Door range is available in a wide range of sizes to suit your individual needs. Please fill in the form below to enquire. -
AQUIKO Square Flap Valves offer a simple yet effective method of flood prevention. Installed in a variety of conditions to prevent backflow into outlets and minimise the risk of flooding. The flap valve comprises a door (the flap) with a hinge at the top which allows fluid to pass in one direction but not the other. The humble flap valve may seem simple yet to make a simple solution brilliant requires a lot of thought.







