From roof to cistern
Using rainwater
A third of daily water consumption goes down the toilet. At the same time, clean drinking water is becoming a scarce resource. The solution lies on the roof: rainwater as an alternative water source for toilet flushing. With Geberit products, this is no problem.
Around 30 per cent of domestic water consumption is accounted for by toilet flushing. Yet this does not require drinking water. In Europe, this realisation has long since set in: over 1.5 million rainwater harvesting systems in Germany, as well as growing installation figures in many countries, point to a clear trend. Rising water prices and sustainability requirements are further drivers of this development.
More than just cisterns
Rainwater is the most obvious place to start. “It can be collected, filtered and used for toilet flushing relatively easily,” says Wolfgang Denk, International Product Manager for Installation Systems at Geberit. However, it can also be used for washing machines or non-potable water outlets, such as in the garden.
Real-world examples confirm its reliability: in Belgium, where the use of rainwater cisterns for toilet flushing is required by law in new buildings, hundreds of thousands of toilets are already being flushed with rainwater.
Prerequisite: clear systems rather than compromises
To ensure that rainwater harvesting works safely within a building, a number of requirements must be met. These include the strict separation from drinking water, appropriate filtration and treatment, quality parameters such as specific pH levels, and regular maintenance and inspections. “One thing is crucial in any case: the systems must function as a whole – not as individual components,” says Wolfgang Denk.
This is precisely where Geberit comes in, managing the flow of water from roof drainage, through the supply pipes, to its use in cisterns and toilets, and finally into the drainage system.
Water – the strategic resource of the future
The trend is clear: in future, buildings will increasingly be designed with separate water systems. What is still regarded as an additional solution today is becoming the norm. Those who embrace these technologies early on not only reduce their consumption of drinking water but also enhance the efficiency and sustainability of their buildings. Or to put it another way: the smartest flush uses exactly the kind and amount of water required – no more and no less.
Geberit products are approved for rainwater harvesting in numerous applications.
1. All drainage systems.
2. The Geberit supply systems Geberit FlowFit, Mepla and Mapress stainless steel.
3.
- All Geberit concealed cisterns of the Sigma, Omega, Delta and Alpha types
- All Geberit exposed cisterns
- Geberit fill valves, types 333 and 383
- Geberit flush valves, types 212 and 208
4. All Geberit toilets
These components form part of a rainwater harvesting system
5. Rainwater tank: Water enters the rainwater tank via the roof. Larger particles of dirt are filtered out before entering the tank. Smaller particles sink to the bottom or float on the surface. The usable water is therefore drawn from the middle layer.
6. Filter: Before the rainwater is distributed to the various tap points, it flows through a filter system which brings it up to the required quality standard.
These supply points are also suitable for rainwater
7. Non-potable water supply points, e.g. for garden watering.
8. Washing machine
