Water saving in toilets

photo Water saving in toilets


Conventional toilet tanks contain between 6 litres (the most recent models) and 15 litres (the oldest models) of potable water. Dual flush toilets have been on the market for a number of years. Even without replacing all installations, simple low-cost measures can be taken to economise water. Water savings can range from 30 to 50%, depending on models.


Standard tanks hold from 9 to 12 litres. Manufacturers now propose more effective and economical dual flush models that use 3 or 6 litres per flush. New flush mechanisms can include a stop mechanism, or dual flush systems, using either half a tank, or the full tank of water. Substantial savings can be made, on the condition that users are clearly informed of how the flush mechanism works.


 - contact different suppliers
 - do a budget study to see if replacing toilet flush systems is profitable
 - test different systems before installing them on all toilets


Interruptible flush mechanism: €30-40
Dual flush mechanism: about €35 (avoid the cheapest products); tank (equipment and labour): €100-150
WC sack: €3-7
WC leaflet: about €10


 - water use reduced by 50%
 - significant economic gains In general payback time is short.

Waterless urinals:
- No water consumption or water costs
- Very low cleaning costs
- Eliminates problems with urinal rinsing mechanism
Clean and odour-free environment
- No bacteria (no stagnant water)
- Minimal upkeep


 Some dual flush mechanisms may be less effective than others in actual use, so testing is indispensable.
 - lower pressure may make it necessary to flush twice (depending on models)
 - stop button may not be understood by all users
 - dual flush buttons may not be understood by all users (depending on models, it is not always clear which button is the full flush, and which is the half tank flush)
 - instructions for use may need to be posted for some models