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Why choose a downpipe filter over a diverter

Posted by Callum VP, on September 22, 2020.

If you are thinking of ways to harvest rainwater to use around the home, many people do so by attaching a device to their roofline guttering system. There are generally two choices available – a downpipe filter or diverter – with the former offering better results. But why choose a downpipe filter over a diverter? We explain all you need to know below. 

What is a rainwater downpipe filter?

A rainwater downpipe filter is a simple device that can be connected to the drain downpipe to harvest water for reuse around the home. Once installed they filter out leaves, stones, insects and other unwanted particles into the drainage below, leaving behind clean water that can be directed into a water butt. 

There are two types available from Garantia UK: 

  • Avanti: Offers a fast and efficient way to install a downpipe filter, taking only 5 minutes to complete. Use the supplied drill bit and hose pipe to create the hole and link the downpipe to the water tank and let nature do the rest.
  • Rapido: This works in a very similar way to the Speedy product, so you can have everything completed in a short space of time.

How do you install a downpipe filter?

Follow these steps to install a downpipe filter:

  • Ensure the ground is level and stable as possible before starting installation. 
  • The downpipe filter needs to be connected to the downpipe using a cordless drill with the special attachment that can bore a hole in both the pipe and water butt. 
  • Featured in the tank will be a hole to fit the inlet seal which can be connected to filter with the supplied hose piping.

What is a rainwater diverter?

A rainwater diverter works in a similar way to a downpipe filter, connecting the roofline system to a water storage tank. There are a number of different types and sizes available, from rigid to flexible and round to square, giving you the option to choose the one that best suits the current system in place on your property. 

The big difference between a downpipe filter and a diverter is the former removes potential contaminants, while the latter only diverts some of water without any sort of filtering involved.

How do you install a rainwater diverter?

  • Make a mark of the height of the water butt on the downpipe and measure 3cm below this to create a cut mark. 
  • Using a hacksaw or other suitable cutting device, saw down the downpipe to the lower mark. 
  • Attach the rainwater diverter to the shortened downpipe. 
  • Using the correct drill bit create an appropriate sized hole in the water butt for the connecting pipe. 
  • Place the connector in the water butt hole and connect it to the hole drilled into the pipe.

Why choose a downpipe filter over a diverter?

While diverters can help capture a similar amount of water, the quality of the water itself will not be as clean as anything that has passed through a downpipe filter. As we explain below, filtering allows you to have cleaner water that can be used more safely around the home to the benefit of everyone living there.

What are the benefits of a downpipe filter?

Lower water bills

Installing a downpipe filter on a property that uses a metered water system will give you the chance to cut down on water bills each year. The harvested water can be stored and used on things such as cleaning the car, watering the garden and cleaning around the home for some domestic house chores, instantly reducing the amount of water being sourced from the tap. 

Chemical-free water 

Whilst there are strict guidelines in place for water providers in the UK, it can still be exposed to a number of contaminants before it reaches your home. A downpipe filter is able to filter some of these out to ensure you have cleaner water to use. In particular, your garden will really benefit as it responds better to rainwater than water from the tap, helping plants to grow for longer and creating a better space for the family in the process. This is not something a downpipe diverter is able to offer. 

Reduced ground saturation 

Sometimes the guttering system on your property can work so well that it has a negative effect on the drainage system at ground level. This is especially true when there is a large amount of rainfall, which can lead to overflowing and oversaturation of the ground. Not only can this create muddy areas, but also unstable ground and potentially flooding. A downpipe filter reduces the flow of water going into the gutter, which minimises the likelihood of saturation occurring

Easy installation

In the past it was more difficult to install a downpipe filter due to the sawing down of the pipe which took a lot of time and effort. However, thanks to advancements in modern technology, the installation process is much easier and requires far less effort. All you need is a drill to connect with the special drill bit provided in our installation packs, and in a matter of minutes you can have everything in place that will allow you to enjoy the benefits of rainwater harvesting. 

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