California will become the first state to require low-flow toilets in nearly all homes, apartment buildings and businesses under a law that will go into effect in January.

The water-conserving measure also requires low-flow shower heads and interior faucets for single-family homes built before 1994. (Homes built since were required to have these when new.)

Owners of single-family homes built before 1994 may see an immediate effect if they remodel but don't have low-flow fixtures. Beginning Jan. 1, they won't be able to get final approval for a variety of home improvements -- from window replacements to room additions -- unless the low-flow plumbing fixtures are installed throughout the property.

The law requires that all pre-1994 homes be retrofitted with low-flow plumbing fixtures by 2017, and that the owner disclose noncomplying fixtures when selling the property. Businesses and multifamily buildings also must disclose whether they meet the law, when selling property after that date.

Building inspectors say they won't become "toilet police," but they do expect toilets to be replaced as people sell their homes or make renovations.

Coupled with regular attention to leaks, replacement of high-flow toilets can cut per-person water use by 35 percent, according to estimates.


The new rules give owners of commercial property or multifamily buildings until 2019 to make sure water-saving toilets, faucets, shower heads and urinals are installed in their properties. Beginning in January, those owners must replace noncomplying fixtures serving an area being renovated, if the cost of the renovation exceeds $150,000. They must retrofit the entire building if they make an addition exceeding 10 percent of the floor space. And they must replace all inefficient fixtures in a room in which they are making other improvements.

Low-flow toilets cost as little as $100 and can surpass $800. It is estimated that switching to a low-flow model will save $1 to $2.50 a month on an average homeowner's monthly water bill, and actual water savings are estimated to be 10,000 gallons a year per toilet.

Some of the first low-flow toilets, introduced in the 1990s, didn't really save water because they required more than one flush, critics say. But the design of low-flow toilets has improved dramatically. Current low-flow toilets are required by the state to average no higher than 1.28 gallons per flush.