On Tank
Flap Valves
Flap valves fit to overflow and outlet pipes and open to let water out, then close to stop pests, vermin and stormwater coming back in. Vented screen versions also let the pipe breathe while keeping mosquitoes out; non-vented versions seal the line for a clean one-way exit.
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Secure your rainwater system
Once water is in your tank, the job is to keep it clean. Sealing your system against pests, light and backflow protects the water you have worked to collect and stops new contaminants getting in.
The 12 Steps of Rain Harvesting™
Frequently asked questions
What's the difference between a vented and non-vented flap valve?
What size flap valve do I need?
Where on my system can I install a flap valve?
How do I maintain a flap valve?
Designed by Rain Harvesting™
Need a tailored system design?
Our specialists can design a complete Rain Harvesting™ system for your property or improve an existing one. You’ll receive a detailed report with everything you need to install and maintain it.
The Handbook
The ultimate guide for help and inspiration to start your rainwater harvesting journey today.