manufacturer-provided guidance. Proper maintenance is vital to the long-term per-
formance of non-water urinals.
In general, avoid retrofit options to reduce the flush volume of valves, including valve
inserts that have a lower flush volume, unless the inserts are rated to provide a flush
volume that is compatible with the existing urinal fixture. Confirm compatibility with
the urinal fixture manufacturer, as many new urinal fixture models are designed to
function at several different flush volumes. If the flush volume of the valve insert is
not compatible with the urinal fixture, it may not provide the expected performance,
especially if the original equipment is not designed to handle a reduced flush vol-
When installing new flushing urinals or replacing older, inefficient flushing urinals,
choose WaterSense labeled models.
WaterSense labeled flushing urinals have
been independently certified to use no more than 0.5 gpf, which is at least 50 per-
cent more water-efficient than standard flushing urinals on the market. In addition,
WaterSense labeled flushing urinals must meet specific criteria for flush performance
and drain trap functionality and are designed to be non-adjustable above their rated
flush volume. These features provide for the longevity of water savings. The specifica-
tion is applicable to the following devices:
Urinal fixtures that receive liquid waste and use water to convey the waste
through a trap seal into a gravity drainage system.
Pressurized flushing devices that deliver water to urinal fixtures.
Flush tank (gravity type) flushing devices that deliver water to urinal fixtures.
To ensure high performance and water savings, choose a valve and fixture combina-
tion with matching rated flush volumes.
Non-water urinals can also be considered during urinal installation or replacement.
When looking to install non-water urinals and very low volume flushing urinals (e.g.,
pint per flush urinals), consider the condition and design of the existing plumb-
ing system and the expected usage patterns in order to ensure that these products
will provide the anticipated performance. As a good rule of practice, adhere to the
guidelines outlined in the International Association of Plumbing and Mechanical
Green Plumbing and Mechanical Code Supplement
at least one water supply fixture unit (i.e., a faucet) to be installed on the drainline up-
stream of the fixtures to facilitate drainline flow and rinsing. Supplemental water or
even periodic manual flushing of the drainlines is important because these products
have little to no water going through the drain to flush out any solids that may build
IAPMO. February 2010.
Green Plumbing & Mechanical Code Supplement