Green Week, Day 3: ULFs

The average toilet uses 5 gallons of water per flush.


Low-flow toilets (LFs) use about 3.5 gallons of water per flush.


Ultra low-flow toilets (ULFs) use no more than 1.6 gallons of water per flush.


That's impressive. A more efficient bowl design and (as one website puts it) "increased flushing velocities" make sure that the 1.6 gallon flush is effective.

AND (scoop your jaw up off the ground for a minute 'cause we're not done) we now have Dual Flush Toilets. These are ULFs with an additional option for an ultra ultra low-flush that uses something like 0.8 to 1.1 (depending on the model) gallons of water per flush.

Most models have two buttons on them so the user can decide if the toilet just needs a little rinse or an increased flushing velocity. Some models, like the Sloan ECOS pictured, also use sensors to detect how long a user is in front of it, and automatically selects the smaller flush for short visits. That's right, the potty's timing you in the name of water conservation.

And if it's wrong, you can always hit the button. These models also ship with etched-metal plates clearly and concisely explaining the toilet to users.

The cost of a ULF toilet is comparable to the cost of a regular one, but if you want to get a nicer model it will pay for itself soon enough anyway. And they install just like regular, water-guzzling toilets: no special skills required.