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{"id":773076648023,"title":"Outlet Flap Valve, Anti Flood Non-Return Valve","handle":"flap-valve-anti-flood-non-return-valve","description":"\u003cp\u003ePlease note there are two versions of this valve, this is the outlet flap valve suitable for placing onto the end of plain ended pipe.  The \u003ca href=\"https:\/\/www.freeflush.co.uk\/collections\/commercial-and-agricultural-rainwater-harvesting\/products\/back-flow-prevention-non-return-valve-110mm-160mm-200mm?variant=8269059293271\"\u003eInline flap valve version\u003c\/a\u003e can be found \u003ca href=\"https:\/\/www.freeflush.co.uk\/collections\/commercial-and-agricultural-rainwater-harvesting\/products\/back-flow-prevention-non-return-valve-110mm-160mm-200mm?variant=8269059293271\"\u003ehere\u003c\/a\u003e. \u003c\/p\u003e\n\u003cp\u003eNon Return Valves for drainage and water pipes, available in two sizes 110mm and 160mm. Slips onto the end of pipes. Effective Anti-flood Valve and Rat Barrier Drain Protection.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is a Flap Valve?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFlap Valves are innovative devices used to prevent flooding caused by the back flow of storm water and sewage. Backflow can be caused by intense rain, thaw or floods. The valves prevent backflow into residential and commercial premises via the drain systems, toilets or sewers. Effectively protecting rooms on lower levels against flooding caused by backflow of storm water and sewerage.\u003c\/p\u003e\n\u003cp\u003eWhere the Flap Valve has a metal Faceplates (like these), they are also an effective rat barrier to your drainage system. The metal stops the rodents from chewing through the flap facepate of the non return valve and protects your plumbing system from rats and other rodents from entering buildings.\u003c\/p\u003e\n\u003cp\u003eFlap Valves are installed on a pipe and allow water (and or solids if a soil or drainage pipe) to flow through the pipe as usual, but prevent anything from flowing back in, like flood water, rats or debris. The pressure of the water flowing through the pipe will open the valve, they automatically close when there is nothing flowing through the pipe.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhere Can flap valves be installed? \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThese flap valves are designed to be installed at the end of horizontal sewage pipes entering collection wells, cesspits or on drainage pipes leading storm water to soakaways or rivers. They are sometimes referred to as Outfall Flap Valves.\u003c\/p\u003e\n\u003cp\u003eAvailable to fit either 110mm (4 inch) or 160mm (6\") pipes.\u003c\/p\u003e\n\u003cp\u003eEasy to install. The Non-Return Valve simply slips on to the end of the pipe. The O-ring within the Valve effectively jams the Flap Valve onto the pipe.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTechnical \u003c\/strong\u003e\u003cb\u003eInformation\u003c\/b\u003e\u003c\/p\u003e\n\u003cp\u003eThis flap valve is equipped with a chromium-nickel cover (A) protecting the flap and gasket. Additionally a chromium-nickel cover of the lever (B) has been designed into the Non-Return Valve to protect against rodents, atmospheric and the environmental conditions (eg. river flow). Flap valves have a rubber O-ring on the inside which ensures a tight fit of the valve to the pipe and effectively keeping the valve in place.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSuitable for water, drainage or soil pipes\u003c\/li\u003e\n\u003cli\u003eFits either 110mm or 160mm Pipes\u003c\/li\u003e\n\u003cli\u003eFits over the outside of the pipe\u003c\/li\u003e\n\u003cli\u003eInstalled at the end of the pipe\u003c\/li\u003e\n\u003cli\u003eOperation fully self-activating\u003c\/li\u003e\n\u003cli\u003ePlastic body: high quality polypropylene with increased UV resistance. The material is harmless to the environment and can withstand temperatures up to 95°C as well as resist aggressive chemicals.\u003c\/li\u003e\n\u003cli\u003eStainless chromium-nickel stainless steel Faceplate\u003c\/li\u003e\n\u003cli\u003eConforms to EN-13564-1:2004\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eOther Versions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFlap Valves for Agricultural Land Drains are also available, fitting 72-100mm pipes,\u003c\/li\u003e\n\u003cli\u003eInline Backflow Valves Valves for 50mm waste pipes,\u003c\/li\u003e\n\u003cli\u003e110mm and 160mm Inline Backflow Valves for Horizontal pipes,\u003c\/li\u003e\n\u003cli\u003e110mm and 160mm Inline Backflow Valves for Vertical Pipes.\u003c\/li\u003e\n\u003c\/ul\u003e","published_at":"2018-05-29T10:53:17+01:00","created_at":"2018-05-29T10:58:44+01:00","vendor":"3P","type":"valves","tags":[],"price":3999,"price_min":3999,"price_max":4999,"available":true,"price_varies":true,"compare_at_price":null,"compare_at_price_min":0,"compare_at_price_max":0,"compare_at_price_varies":false,"variants":[{"id":8269088161879,"title":"110mm","option1":"110mm","option2":null,"option3":null,"sku":"KARZBK110","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Outlet Flap Valve, Anti Flood Non-Return Valve - 110mm","public_title":"110mm","options":["110mm"],"price":3999,"weight":1100,"compare_at_price":null,"inventory_quantity":0,"inventory_management":null,"inventory_policy":"deny","barcode":""},{"id":8269088194647,"title":"160mm","option1":"160mm","option2":null,"option3":null,"sku":"KARZBK160","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Outlet Flap Valve, Anti Flood Non-Return Valve - 160mm","public_title":"160mm","options":["160mm"],"price":4999,"weight":1000,"compare_at_price":null,"inventory_quantity":0,"inventory_management":null,"inventory_policy":"deny","barcode":""}],"images":["\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZ_how_it_works.jpg?v=1582917669","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZ_O-ring-detail.jpg?v=1582917669","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK_installation.jpg?v=1582917669","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK_installation_square.jpg?v=1582917669","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_flap_valve.jpg?v=1582917669","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_dimensions.jpg?v=1582917670","\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK160_dimensions.jpg?v=1582917670"],"featured_image":"\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZ_how_it_works.jpg?v=1582917669","options":["Size"],"media":[{"alt":"Outlet Flap Valve, Anti Flood Non-Return Valve - Freeflush Rainwater Harvesting Ltd. 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","id":722845630551,"position":5,"preview_image":{"aspect_ratio":1.617,"height":3318,"width":5364,"src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_flap_valve.jpg?v=1569053013"},"aspect_ratio":1.617,"height":3318,"media_type":"image","src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_flap_valve.jpg?v=1569053013","width":5364},{"alt":"Outlet Flap Valve, Anti Flood Non-Return Valve - Freeflush Rainwater Harvesting Ltd. ","id":722845663319,"position":6,"preview_image":{"aspect_ratio":0.481,"height":800,"width":385,"src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_dimensions.jpg?v=1569053013"},"aspect_ratio":0.481,"height":800,"media_type":"image","src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK110_dimensions.jpg?v=1569053013","width":385},{"alt":"Outlet Flap Valve, Anti Flood Non-Return Valve - Freeflush Rainwater Harvesting Ltd. ","id":722845696087,"position":7,"preview_image":{"aspect_ratio":0.481,"height":800,"width":385,"src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK160_dimensions.jpg?v=1569053013"},"aspect_ratio":0.481,"height":800,"media_type":"image","src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0829\/4323\/products\/KARZBK160_dimensions.jpg?v=1569053013","width":385}],"content":"\u003cp\u003ePlease note there are two versions of this valve, this is the outlet flap valve suitable for placing onto the end of plain ended pipe.  The \u003ca href=\"https:\/\/www.freeflush.co.uk\/collections\/commercial-and-agricultural-rainwater-harvesting\/products\/back-flow-prevention-non-return-valve-110mm-160mm-200mm?variant=8269059293271\"\u003eInline flap valve version\u003c\/a\u003e can be found \u003ca href=\"https:\/\/www.freeflush.co.uk\/collections\/commercial-and-agricultural-rainwater-harvesting\/products\/back-flow-prevention-non-return-valve-110mm-160mm-200mm?variant=8269059293271\"\u003ehere\u003c\/a\u003e. \u003c\/p\u003e\n\u003cp\u003eNon Return Valves for drainage and water pipes, available in two sizes 110mm and 160mm. Slips onto the end of pipes. Effective Anti-flood Valve and Rat Barrier Drain Protection.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is a Flap Valve?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFlap Valves are innovative devices used to prevent flooding caused by the back flow of storm water and sewage. Backflow can be caused by intense rain, thaw or floods. The valves prevent backflow into residential and commercial premises via the drain systems, toilets or sewers. Effectively protecting rooms on lower levels against flooding caused by backflow of storm water and sewerage.\u003c\/p\u003e\n\u003cp\u003eWhere the Flap Valve has a metal Faceplates (like these), they are also an effective rat barrier to your drainage system. The metal stops the rodents from chewing through the flap facepate of the non return valve and protects your plumbing system from rats and other rodents from entering buildings.\u003c\/p\u003e\n\u003cp\u003eFlap Valves are installed on a pipe and allow water (and or solids if a soil or drainage pipe) to flow through the pipe as usual, but prevent anything from flowing back in, like flood water, rats or debris. The pressure of the water flowing through the pipe will open the valve, they automatically close when there is nothing flowing through the pipe.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhere Can flap valves be installed? \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThese flap valves are designed to be installed at the end of horizontal sewage pipes entering collection wells, cesspits or on drainage pipes leading storm water to soakaways or rivers. They are sometimes referred to as Outfall Flap Valves.\u003c\/p\u003e\n\u003cp\u003eAvailable to fit either 110mm (4 inch) or 160mm (6\") pipes.\u003c\/p\u003e\n\u003cp\u003eEasy to install. The Non-Return Valve simply slips on to the end of the pipe. The O-ring within the Valve effectively jams the Flap Valve onto the pipe.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTechnical \u003c\/strong\u003e\u003cb\u003eInformation\u003c\/b\u003e\u003c\/p\u003e\n\u003cp\u003eThis flap valve is equipped with a chromium-nickel cover (A) protecting the flap and gasket. Additionally a chromium-nickel cover of the lever (B) has been designed into the Non-Return Valve to protect against rodents, atmospheric and the environmental conditions (eg. river flow). Flap valves have a rubber O-ring on the inside which ensures a tight fit of the valve to the pipe and effectively keeping the valve in place.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSuitable for water, drainage or soil pipes\u003c\/li\u003e\n\u003cli\u003eFits either 110mm or 160mm Pipes\u003c\/li\u003e\n\u003cli\u003eFits over the outside of the pipe\u003c\/li\u003e\n\u003cli\u003eInstalled at the end of the pipe\u003c\/li\u003e\n\u003cli\u003eOperation fully self-activating\u003c\/li\u003e\n\u003cli\u003ePlastic body: high quality polypropylene with increased UV resistance. The material is harmless to the environment and can withstand temperatures up to 95°C as well as resist aggressive chemicals.\u003c\/li\u003e\n\u003cli\u003eStainless chromium-nickel stainless steel Faceplate\u003c\/li\u003e\n\u003cli\u003eConforms to EN-13564-1:2004\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eOther Versions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFlap Valves for Agricultural Land Drains are also available, fitting 72-100mm pipes,\u003c\/li\u003e\n\u003cli\u003eInline Backflow Valves Valves for 50mm waste pipes,\u003c\/li\u003e\n\u003cli\u003e110mm and 160mm Inline Backflow Valves for Horizontal pipes,\u003c\/li\u003e\n\u003cli\u003e110mm and 160mm Inline Backflow Valves for Vertical Pipes.\u003c\/li\u003e\n\u003c\/ul\u003e"}

Outlet Flap Valve, Anti Flood Non-Return Valve

£39.99
Maximum quantity available reached.

Please note there are two versions of this valve, this is the outlet flap valve suitable for placing onto the end of plain ended pipe.  The Inline flap valve version can be found here

Non Return Valves for drainage and water pipes, available in two sizes 110mm and 160mm. Slips onto the end of pipes. Effective Anti-flood Valve and Rat Barrier Drain Protection.

What is a Flap Valve?

Flap Valves are innovative devices used to prevent flooding caused by the back flow of storm water and sewage. Backflow can be caused by intense rain, thaw or floods. The valves prevent backflow into residential and commercial premises via the drain systems, toilets or sewers. Effectively protecting rooms on lower levels against flooding caused by backflow of storm water and sewerage.

Where the Flap Valve has a metal Faceplates (like these), they are also an effective rat barrier to your drainage system. The metal stops the rodents from chewing through the flap facepate of the non return valve and protects your plumbing system from rats and other rodents from entering buildings.

Flap Valves are installed on a pipe and allow water (and or solids if a soil or drainage pipe) to flow through the pipe as usual, but prevent anything from flowing back in, like flood water, rats or debris. The pressure of the water flowing through the pipe will open the valve, they automatically close when there is nothing flowing through the pipe.

Where Can flap valves be installed? 

These flap valves are designed to be installed at the end of horizontal sewage pipes entering collection wells, cesspits or on drainage pipes leading storm water to soakaways or rivers. They are sometimes referred to as Outfall Flap Valves.

Available to fit either 110mm (4 inch) or 160mm (6") pipes.

Easy to install. The Non-Return Valve simply slips on to the end of the pipe. The O-ring within the Valve effectively jams the Flap Valve onto the pipe.

Technical Information

This flap valve is equipped with a chromium-nickel cover (A) protecting the flap and gasket. Additionally a chromium-nickel cover of the lever (B) has been designed into the Non-Return Valve to protect against rodents, atmospheric and the environmental conditions (eg. river flow). Flap valves have a rubber O-ring on the inside which ensures a tight fit of the valve to the pipe and effectively keeping the valve in place.

  • Suitable for water, drainage or soil pipes
  • Fits either 110mm or 160mm Pipes
  • Fits over the outside of the pipe
  • Installed at the end of the pipe
  • Operation fully self-activating
  • Plastic body: high quality polypropylene with increased UV resistance. The material is harmless to the environment and can withstand temperatures up to 95°C as well as resist aggressive chemicals.
  • Stainless chromium-nickel stainless steel Faceplate
  • Conforms to EN-13564-1:2004

Other Versions

  • Flap Valves for Agricultural Land Drains are also available, fitting 72-100mm pipes,
  • Inline Backflow Valves Valves for 50mm waste pipes,
  • 110mm and 160mm Inline Backflow Valves for Horizontal pipes,
  • 110mm and 160mm Inline Backflow Valves for Vertical Pipes.
There is no additional documentation for this product

W.C. 30.3.20 Dispatch planned as normal. All couriers are observing social distancing. All couriers are working under "Christmas Workload" due to increase in online orders -delays expected.  

27.3.20 Dispatch planned as normal. 

26.3.20 Dispatch planned as normal. 

25.3.20 Dispatch planned as normal. 

24.3.20 Dispatch planned as normal. 

23.3.20 A number of couriers have suspended delivery time guarantees. If your order is urgent please get in touch before ordering. 

20.3.20 Dispatch planned as normal.

19.3.20 Royal Mail Special Delivery Guaranteed by 1pm Announcement:

We will no longer guarantee deliveries by 1pm the next working day for items posted from Thursday 19 March 2020 onwards.  As a result, we will not consider a claim for delay for items posted using the Special Delivery Guaranteed by 1pm service from that date.  In addition we will not during this period offer our Consequential Loss service and we will not accept any related claims. 

18.3.20 Dispatch planned as normal. 

17.3.20 Due to the current coronavirus situation Royal Mail are no longer asking recipient’s to sign for items delivered on or after Saturday 14 March 2020.

17.3.20 Daily dispatch (Royal Mail, Hermes, FedEx) will continue as normal. 

17.3.20 UK stock affected: 

211702 - 500l Terracotta water butt 

12.3.20 * Due to the Coronovirus Pandemic a number of our suppliers and couriers have provided indications of potential delay of goods and deliveries. Many of the goods we supply are manufactured in the EU where action is being taken to slow the spread of the virus. This may have an impact on your order. Please get in touch to see if a certain product/order is affected. As it stands this should have no impact on UK stock and deliveries.*

We're a Manchester based company and ship to the UK at our standard rates. Please get in touch if you are based the Highlands or a UK island. 

We also ship all small items (<2kg) to the EU at standard rates which can be seen at checkout. For larger items or quotes for other destinations please get in touch.

We ship all small items (<2kg) Worldwide.  

Stock items will be dispatched on the day of order, if ordered before 1pm.

The majority of items are shipped with Royal Mail with the following target delivery times.

Standard shipping (2nd class) allows basic tracking (dispatch and delivery). 

"1st class signed for" provides full tracking. 

A loss/replacement can only be pursued in line with the target delivery times of the courier. 

Bulky items (and pallet deliveries) are dispatched within 2 working days. We will request a contact number if this has not been provided at checkout. 

Some items are made to order (bespoke) and details are given on the listing for dispatch times.  If for any reason we anticipate a delay on our normal dispatch time we will  contact you to let you know.

Occasionally there are delays. We shall not be liable for any direct or indirect losses, costs, damages or expenses incurred by you or any other person for any delays in delivery.

We are an environment centric business and as such we try to minimise our waste. Our packaging is usually recycled and we make efficient use of packaging to minimise wastage.