There’s a good chance that the building codes used years ago when your water heater was installed have changed. And now, if you are in the market to replace that water heater — either by yourself or professionally — it’s a smart idea to make sure the plumbing codes you follow are the latest available.

Little details during an installation can make or break a safety inspection. For example, did you know that water tank strapping must be located a minimum of 4 in. above the gas valve? And that depending on ignition type, not all water heaters must be raised 18 in. off the floor?

To avoid a serious safety issue, fuel-fired water heaters are prohibited in storage closets. It would then seem logical that water heaters should also be prohibited in bathrooms and bedrooms, but depending on the ventilation available, exceptions apply.

In this free excerpt from The Taunton Press title, Code Check Plumbing, 3rd Edition, learn about the requirements for water heater locations, access areas and working spaces before you or your installer take on the job.

And, if you have plans to upgrade your water heater, consider installing a tankless water heater. These “on-demand” water heaters use a heat exchanger within their housing to heat water as it circulates through the burner, creating a situation where hot water is almost always available. Information on sizing, venting and gas supply lines for tankless water heaters is also included in the excerpt. — Jean Paul Vellotti

A note about abbreviations

To help you decipher the abbreviations used in Code Check Plumbing, please refer to the following list:

BA = bathroom
BR = bedroom
BTU = British thermal unit(s)
EXC = signals an exception to the code
FVIR = flammable vapor ignition resistant
IRC = International Residential Code
L&L = listed & labeled
MANU = typically required by manufacturer’s installation instructions
OR = signals an alternative to the code
PRV = pressure relief valve
SDC = seismic design category
TPRV = temperature and pressure relief valve
UPC = Uniform Plumbing Code
WH = water heater

Redwood Kardon, Douglas Hansen, and Michael Casey are certified building inspectors and building code educators. Jean Paul Vellotti is Fine Homebuilding’s managing editor for the Web.