Rainwater Harvesting

The RainCycle® has been designed to recycle rainwater which would normally go to waste. T-T have three different systems available - Garden, Domestic or Commercial, our rainwater harvesting systems can be tailored to suit your requirements.

Why collect rain?

Each person uses on average 80-100 gallons of water every single day. With the ever-increasing population, this is putting strains on our water system not to mention the cost this incurs on water bills.

Rainwater harvesting and recycling rain cannot completely replace mains water due to the fact that we need potable water; rainwater is not treated to this standard, however, a lot of the water we use on a daily basis doesn't need water that is treated to this standard, for example, flushing toilets, washing clothes, watering plants and the garden and cleaning vehicles. Rainwater harvesting is perfect for these applications. As rainwater is free and sustainable it often makes sense to install a system to cater for these tasks.

Not only is there the money and sustainability benefits of utilising rainwater, rainwater is often soft so doesn't contain the limescale content as in hard water areas.

How does rainwater harvesting work?

Using a typical rainwater roof run off drainage system, a tank is installed in the ground to collect this water and filter before holding in  a storage tank. This can then be pumped to appropriate outlets around a domestic or commercial property.

How does a typical RainCycle rainwater harvesting system operate?

Rainwater is captured from the roof and diverted into the rainwater harvesting system, which then flows into the volume filter; as water flows through the inlet the level builds up and is equally distributed across the cascade.

The largest dirt particles flow over the primary filter cascading directly to the stormwater drain or soak-away.

The pre-filtered water then flows over the secondary filter sieve (mesh size 0.65mm) and into the underground tank, via a calmed inlet which prevents disturbance of the settled sedimentation layer at the base of the chamber, ready for use.

  • The underground tank ranges in chamber sizes from 1,350 litres to 13,000 litres with the option of bespoke chambers up to 90,000 litres
  • Pump chambers are well manufactured and engineered and have passed rigorous tests
  • Our standard pump chamber is made of strong, medium density polyethylene, with the bespoke chambers being made from GRP
  • Units can be adapted to suit individual requirements at manufacturing stage
  • Available on short lead-times
  • Control panels are included as standard
  • A comprehensive installation manual is included as standard 
  • Systems incorporating a back-up from the mains water supply require a type AA or AB backflow prevention device, if using a direct system we offer a mains water top-up box which is complete with built in AA air gap.
Water and money saving benefits

Utilising a rainwater harvesting system means water that would usually run down the drain is recycled and can be used in the garden and in domestic appliances.  By recycling this water you are making your home more sustainable and can reduce your potable water usage by up to 46%. Therefore by using less potable water, you can save on your water household bills.


The system needs minimal maintenance, but we would suggest that your RainCycle rainwater harvesting system is inspected by our Service Engineers at least once per year to ensure that all filters are clean and clear, and sediment levels are acceptable to ensure optimum performance.


Once the electricity supply and liquid connections are made the RainCycle system is ready to be commissioned. Our engineers can undertake a full check of the installation, ensuring that it is safe and to specification. Checks are carried out to verify the RainCycle systems operational sequence and its overall function.

A full installation and commissioning report are provided to the site representatives.

Health and Safety

T-T attaches the highest priority to Health and Safety issues. All Service Engineers work in teams of two and are fully qualified for:

  • Confined space working
  • First aid
  • 17th and 18th edition of IEE wiring regulations

Where multiple dwellings are drawing off one RainCycle we would recommend that a metering system is introduced.

Sizing of the RainCycle

The amount of water available for use is dependant on the rainwater collection area, which will normally be from the roof, and local rainfall, which varies from area to area. Usage of water needs to be considered; for normal domestic use, we take that a nominal amount of total water used can be rainwater and will depend on the usage data you provide in the RainCycle questionnaire.

For commercial rainwater harvesting systems, this will vary due to usage being considerably higher, for example where residents may want to use more water for the garden.

To help us make the best selection for your application, please complete the RainCycle questionnaire.

Considerations for selecting a RainCycle rainwater harvesting system:

The RainCycle can be happily introduced into most schemes as part of a new build or as a retrofit, but care should be taken to understand the limitations and maintenance requirements.

a) Small schemes will have an extended payback period.

b) Recovered rainwater is not suitable for human consumption.

c) All taps and pipework used to convey rainwater must be clearly labelled.

d) Systems incorporating a back-up from the mains water supply require a type AA or AB backflow prevention device.

- A type AA air gap conforming to EN 13076:2003 to prevent pollution by backflow of potable water - unrestricted air gap.

- A type AB air gap conforming to EN 13077:2008 to prevent pollution by backflow of potable water - air gap with non-circular overflow.

e) Gutters used for collecting the rain water should be checked and cleaned regularly. Avoid areas where large amounts of bird or animal droppings are likely.

f) The RainCycle system should be checked by the user periodically to ensure that the system is clean and it operates correctly.

g) Every 12 months the RainCycle system should be inspected and serviced by a competent engineer. T-T offer a reassuring and economical Service Agreement Scheme.

h) Care should be taken when selecting roofs for rainwater collection. Only use roofs that are in a good state of repair and away from areas of heavy leaf deposits. Avoid using roofs covered in asbestos, old steel corrugation that is rusty and roofs with mastic covering or repairs, as the quality of water collected will be impaired.

Not sure what you need?

Get in touch with one our team, we can help.

T-T Pumps Ltd
Head Office
Onneley Works
Newcastle Road
United Kingdom
Monday - Friday

8am - 5.30pm