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Water Provider Incentives

Water provider incentives- save up to £722 per plot. What is it? Anglian Water and Severn Trent have launched schemes to incentivise water efficient new homes. The...

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Truro Case Study
Truro Case Study

RAIN ACTIV® INSTALLATION CASE STUDY TRURO, CORNWALL Provided combined storm attenuation and rainwater harvesting. Reduced peak stormwater discharge rate to...

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Rain Activ- Supporter of Susdrain. The UK’s sustainable drainage community.
Rain Activ- Supporter of Susdrain. The UK’s sustainable drainage community.

Rain Activ has become a member of an impressive cross-sectoral group of organisations dedicated to supporting, further demonstrating growing industry...

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New? Maybe Start Here

Rainwater harvesting and SuDS systems can look complex and daunting to begin with.

Here at Rainwater Harvesting Ltd we’re committed to helping you every step of the way.

Rainwater Harvesting.

The principal of rainwater harvesting is to collect, filter and store rainwater from your roof.
This harvested rainwater can be used for toilets, washing machines and in the garden. Giving you significant reductions to your bills as well as making your home more sustainable.


In almost all cases we advise the use of below ground tanks. This is for a number of reasons;
•    No space is taken up and the appearance of your home isn’t altered.
•    When stored below ground, the collected rainwater has no access to light and stays very cool. Both factors make bacterial growth impossible, thus keeping the quality of the water very high.
•    When below ground, the tanks are frost protected.

The next question is how big should the tank be? Normally measured by capacity (like 5000 litres) and based on the size of the property (call us- we can help here).

To find your ideal tank size we have a simple to use tank size calculator.

We highly recommend the use of ‘shallow dig’ underground tanks. These have a larger footprint but are only around 1 – 1.5m in depth making installation simple, safe and cost effective.
Tanks are normally sited in the garden or can be placed in driveways when an optional lid is supplied.
None of our tanks need concreting in, just backfill with a compactable aggregate.   

Choosing a system.

Next, there are some decisions to make about the system you need and what you want to use the rainwater for.
We can supply systems for either just garden use, or domestic systems for toilets and washing machines.

All our systems use the same tanks, self cleaning filter and submersible pump.
The difference is for domestic systems, we provide a device that switches over the supply to mains water in case of a drought so your loo will still flush (known as Mains Back-up).

One further consideration is that domestic systems are available in either ‘direct feed’ or ‘gravity feed’ configurations.
Direct feed systems are the industry standard in the UK, are slightly cheaper, and do not require space for a small header tank.
Our gravity feed system known as ‘Rain Director’ is a firm customer favourite due to it’s considerable reduction in energy use, user configurations and automatic backup in every eventuality. (Such as low rainwater, power cut or pump failure.)

Every system we sell is a full ‘turn key’ kit including everything required for installation. This includes things like the specialist exterior rainwater pipe, interior labels and connections.

We also have a tech team ready to call at any time to assist with questions.    

What about ‘SuDS’

SuDS stands for ‘Sustainable Drainage Systems’ and are designed to prevent urban flooding by limiting the rate of water entering the drains during a heavy storm.

It only needs considering if you;
•    Are unable to route the excess water from the tank to a soakaway. (So the overflow needs connecting to the drain/sewer.)
•    Your development is on a clay or high water table site.
•    During planning the council has stipulated you must install SuDS. (Often given in the form of a ‘maximum discharge rate’.)

Our Rain Activ system is a new and innovative solution to provide SuDS at a much lower cost than previously possible.
Better still, Rain Activ combines rainwater harvesting with SuDS making it not just more cost effective but also more sustainable compared to other systems on the market.

Where next?

Why not check out our videos page below that explain our systems really well?

We also have an FAQ page that gives you a better idea of the key questions such as;

Does the Rainwater smell or leave stains? (No!)
How much maintenance is required? (One quick filter check per year)

You can always call on 01733 405111 or use our contact form if you have any questions or help with specifying the right system for you.