Contact Us

Flap Valves by Fernco

Fernco Flap Valves (previously known as Flexseal) are made of HDPE to offer a durable, cost-effective solution that prevents backflow through drain or sewerage pipes. The range includes a variety of standard and bespoke / custom flap valves designed to defend environments, residences and properties against rising water levels.

Benefits of Fernco Flap Valves

  • Manufactured in the UK, trusted by the Environment Agency and Water Companies
  • HDPE (high-density polyethylene) is lighter weight than traditional cast iron flap valves, reducing the installation complexity and costs
  • Heavy-duty HDPE can withstand impact from debris in marine and river settings, unlike lighter plastics
  • Inherently waterproof design eliminates the need for additional maintenance like tapes or sealants
  • HDPE material deters theft due to its minimal scrap value
  • Low to zero maintenance required
  • Access to technical support from Flexseal / Fernco
  • Life expectancy of up to 50 years with proper care and regular inspections
  • Manufactured to class 5 standard of DIN 19569-4 and BS7775
  • 316 steel as standard
  • Fully recyclable for sustainability

How Do Flap Valves Work?

Installed at the open end of pipelines or culverts, these one-way flap valves allow downstream water to exit the pipe through a one-way flap door, whilst preventing rising water levels from entering the pipe and flowing back up the system and flooding the protected area. Fernco's HDPE flap valves are corrosion-resistant, lightweight, and function as reliable non-return valves and check valves. Unlike traditional cast iron valves, Fernco Flap Valves are manufactured from HDPE, offering strength, corrosion resistance and easy maintenance. Fernco flap valves combine various seals to ensure leakage into the pipe system is prevented. They feature integrated watertight seals for straightforward installation without the need for grout.

Flap Valve Mounting Options Available:

Wall Mounted Flap Valve

Suitable for DN100 pipe to DN600 pipe sizes, larger sizes available upon request.

Spigot Mounted Flap Valve

Fits DN100 pipe to DN600 pipe sizes, larger sizes available upon request.

Flange Mounted Flap Valve (available on request)

Sizing options for DN100 pipe to DN600 pipe with larger sizes available upon request.

Flap Valve Mounting Sets include:

  • M8 capsules & fixings for DN100-300 sizes or M12 capsules & fixings for DN400 sizes and larger
  • Chemical resin capsules
  • Stainless Steel 1.4401 (316) anchor fixings

Other Fernco / Flexseal Water Management:

If you have any questions or enquiries regarding water management and the specific Flexseal / Fernco products you require, please contact us via live chat, phone at 03302 230 275, or email at [email protected].
Flap Valves