BACKFLOW & CROSSFLOW - HOW DOES MULTIFLAP HELP?

Let’s take a break from talking about rats and snakes and give some space to the un-sung added benefits of the MultiFlap valve when it comes to crossflow and backflow in your plumbing.

What are crossflow and backflow? Backflow is when water flow is reversed in your plumbing system and water flows backward against its intended direction and into the clean water supply (back into your toilet for example). It can be caused by a number of factors including back siphonage where a vacuum creates a pulling force or by back pressure, where higher downstream pressure pushes water backward.

It is a legal requirement in the UK that all water fittings be installed with adequate devices to prevent contaminated water from flowing back into the mains supply, as defined in the Water Supply (Water Fittings) Regulations 1999 (or similar byelaws in Scotland).

Crossflow is when waste from one supply flows into another, this can cause blockages and contamination. For example, waste from one toilet flows into another branch of a system rather than continuing down into the soil stack. This can happen where multiple toilets are present and where toilet systems have not been optimally fitted to stagger the connections to the soil stack. Especially common in back to back toilets and the hospitality sector.

MultiFlap is a non-return valve, it prevents backflow and reduces by only allowing fluid to flow in one direction. It does this by immediately closing its flap after the flush water and contents have passed through it. This is the same flap that prevents creatures such as snakes and rats from gaining access to your toilet and then your home.

The MultiFlap is spring loaded with a spring, hinge and pin made from marine grade stainless steel, it has a polypropylene valve with a Thermo-Plastic-Elastomer seal that is over-moulded to the body – this means that if a reverse flow pushes against the flap, it creates a tight seal against the housing that blocks the backflow.

MultiFlaps also operate as an anti-cross flow device, allowing toilets to be fitted back to back and closer together; reducing the amount of pipework required to prevent cross-flow.

If you need any further information on please just drop us an email and we will be happy to help.