Need to understand the unfamiliar jargon your friendly plumber speaks? Here’s a glossary of some common terms used in residential and commercial plumbing.
ABS: Stands for Aristocraft bristone styrene, a type of stiff black plastic piping used for waste, vent, and drain lines.
“A” Valve: A manual shut-off valve for gas.
Access Panel: An opening in a wall near a fixture allowing access for service.
Acidity: The amount of concentration of acid in water, used to neutralize alkalinity. Also referred to as pH.
Adaptor: A fitting that ties together different types of pipe.
Aerator: A device on the end of a spout that mixes air into flowing water to enhance or control flow.
Alkali: A water-soluble mineral compound such as a bicarbonate and carbonate compound when it is present in the water.
Alkalinity: A measurement of minerals in a water supply that determine alkaline conditions, or the ability to neutralize acid. Also referred to as pH.
Ambient Temperature: Average temperature of air around an appliance; important for ice-making refrigerators, water heaters and other devices.
Angular Discharge Tube: A tube that changes water flow direction to 90 degrees.
Angle Stop: A shutoff valve between a faucet and water pipes normally used in emergency repair.
Anode Rod: A rod installed in a water heater to protect the tank against corrosion, help extend tank life.
Anti-Siphon: Device that prevents backflow of liquid into a plumbing system. Used on sprinkler systems to prevent water from trickling back into the supply that is feeding it.
Backflow: Flow of water or other liquids, mixtures, or substances into a potable water supply system.
Back Flow Preventer: A device to prevent water from traveling back into the main distribution system, especially into a potable water supply. Generally required for kitchen sprayers, handheld showers, pullout faucet spouts, and sprinkler systems.
Back Pressure: Pressure that resists fluid flow in a system of pipes.
Back Siphonage: Negative pressure that results in backflow.
Backup: Overflow caused by a drain stoppage such as a clogged drain or clogged toilet.
Backwater Valve: A valve on the sewer line that keeps sewage from flowing backward into a building.
Ball Check Valve: A valve using a ball that seals against a seat to stop water flow.
Ballcock: A fill valve that controls water flow of water into a toilet tank.
Basin Wrench: A long-handled wrench with jaws mounted on a swivel to reach and adjust nuts that fasten faucets to an installed sink.
Bidet (pronounced Bid-day): A personal hygiene fixture with a basin, hot and cold faucets and a sprayer, used for washing genitals and posterior areas of the body.
Bleed: To drain a hose tube, or pipe of excess air by opening a valve at the end or systematically removing the air by force or suction.
Boiler: A sealed tank where water is heated and turned to steam for power or hot water.
Catch Basin: Large underground container, with a grate on the top, for collection of storm water run-off. It catches or collects dirt and other debris and prevents them from polluting streams and lakes.
Cesspool: A lined excavation, hole or pit in the ground that takes in drainage, retaining organic matter and solids while allowing liquids to seep through sides and bottom.
Check Valve: A type of backflow preventer installed in a pipe allowing water to flow in only one direction.
Cleanout Plug: A plug in a sink trap or drain pipe that gives access for clearing a clog.
Closet: A plumbing term for a toilet, i.e. “water closet.”
Closet Auger: A flexible rod having a curved end, used to remove clogs by way of a toilet’s built-in trap.
Closet Bend: A fitting in a curved shape, mounted below the toilet connecting the closet flange to the toilet drain.
Closet Flange: An anchoring ring secured to the floor, attaching to the closet bend. Closet bolts go through the flange to secure the toilet in place.
Compression Valve: A valve often used for water faucets, opened or closed by a horizontal disk moving up and down on a threaded stem.
CPVC (Chlorinated Polyvinyl Chloride): Plastic pipe used in water supply systems, where building codes permit.
Dip Tube: A tube inside a water heater that distributes cold water to the tank bottom.
Discharge Tube: A tube connecting a disposer or sump pump to a drain line.
Disposal Field: A series of trenches that disperses effluent from a septic tank so that it distributes uniformly into natural soil.
Diverter: Valves directing water to various fixtures such as sinks, showers, tubs, and bidets.
DWV: Abbreviation for the necessary functions of a sewage system: Drain, Waste and Vent.
Earthquake Strap: A metal strap that secures a water heater to a building frame or foundation in earthquake-prone regions.
Efficiency: A product’s ability to utilize input energy, expressed as a percentage.
Effluent: Septic system liquid waste.
Elbow: A pipe fitting, also called an ell, that changes the line’s direction anywhere from 22 to 90 degrees.
Escutcheon: A decorative metal trim shield under a faucet handle that covers the stem and the hole in a fixture or a wall where a pipe enters.
Female Fitting: A fitting into which another fitting is inserted.
Finish Plumbing: Installation of fixtures that make a plumbing system usable.
Fixture: Devices that provide a supply of water and/or its disposal, such as sinks, tubs, toilets.
Flapper Valve: The part on the bottom of a toilet tank that opens to allow water to flow into the bowl.
Float Ball: A floating sphere connected to the ballcock inside the tank that rises or falls with changing water levels and opens or closes the ballcock.
Floor Flange: A fitting that connects a toilet to a floor drain.
Flux: A paste applied to copper pipes and fittings before soldering to help them fuse together and to prevent oxidation.
Footprint: The area of floor space taken up by an appliance.
French Drain: A covered ditch containing a layer of fitted or loose stone or other pervious material.
Gate: A device that controls water flow in a conduit, pipe, or tunnel.
Gate Diverter: A pop-up lever on a tub faucet that activates the diverter valve.
Gravity Operated Toilet: A toilet that relies on the natural downward pressure of water in a toilet tank to flush the toilet effectively.
Gray Water: Wastewater from sinks, showers, and bathtubs, but not toilets.
Hose Bibb: An outdoor faucet, also used to supply washing machines.
House Trap: U-shaped fitting with two adjacent cleanout plugs visible at floor level if main drain runs under floor.
I.D.: Abbreviation for Inside Diameter. All pipes are sized according to their inside diameter.
Indirect Wastes: Waste pipe used to convey gray water by discharging it into a plumbing fixture such as a floor drain.
Johnni-bolts: Closet bolts, used to mount toilet bowls to the closet flange.
Lavatory (Lav): A fixed bowl or basin with running water and drainage for washing. Also used to refer to a bathroom.
Leach Field: Porous soil area through which septic tank leach lines run to empty the treated waste.
Lock Nut: Nut fitted into a piece of pipe and screwed onto another pipe to join the two pieces.
Main: The primary artery of supply of the water supply or drain system in which all the branches connect. In the case of drains, known as the Main Vent.
Male Threads: Threads on the outside of pipes and fittings.
Malleable Fittings: Fittings made of metal that is soft and pliable.
Manifold: A fitting that connects a number of branches to the main; serves as a distribution point.
Mechanicals: The wiring, plumbing and heating and cooling systems in a building; also the components with moving parts such as furnaces, plumbing fixtures, etc.
Nipple: A short length of pipe installed between couplings or other fittings.
O.D.: Abbreviation for Outside Diameter.
O-Ring: Round rubber washer used to create a watertight seal, chiefly around valve stems.
Outlet Sewer: Pipe section in a septic system that runs between the tank and the drainage field.
Packing: Fibrous material that is used on faucets to prevent leaks.
Packing Nut: Nut that holds a faucet stem in place and secures the packing material.
PB (Polybutylene): Flexible plastic tubing used in water supply systems where allowed by code.
Peak Hour Demand: Time when the largest demand for hot water is needed.
pH: Potential Hydrogen, the hydrogen ion concentration of water to denote acidity or alkalinity, measured on a scale of 0 to 14. Below 7 denotes acidity; above 7 denotes alkalinity.
Pipe Dope: Slang for pipe-joint compound. Substance applied to threaded fittings to create a watertight seal.
Pitch: Downward slope of a drainpipe in the direction of the water flow.
Plumb: Precisely vertical. Also to test for, or to make vertical. Also to perform plumbing work.
Plumber’s Putty: Pliable, popular putty used to seal joints between drain pieces and fixture surfaces.
Plumbing Tree: Prefabricated set of drain waste, vent, and supply lines.
Plunger: An instrument usually with a rubber head, used to create suction in a drain line or a toilet to push a clog through the line.
Pop-Up Drain: Type of drain assembly for lavatory and bath. When a lavatory lift rod or bath overflow plate lever is lifted, the pop-up drain closes so the lavatory or tub retains water.
Pressure Tank: Device used to pump water from a well.
PVC (Polyvinyl Chloride): A rigid white or cream-colored plastic pipe used in non-pressure systems, such as drainage, waste, and vent systems.
Rated Storage Volume: Quantity of water stored in a tank.
Reamer: A grinding tool used to level or remove burrs from valve seats in faucets so that the valve stem will fit properly.
Reducer: A fitting that connects pipes of different sizes together.
Rim Holes: A series of small holes in the underside of a toilet rim, around the circumference of the bowl. Incoming water flows down into the bowl through these holes, creating a rinse effect or wash over the entire inner surface of the bowl.
Riser: A vertical metal (usually copper) or plastic tube or assembly that connects a faucet to a water supply stop valve.
Roof Flashing: Sheet metal installed at any break in a shingled roof to prevent leaks around sewer vents, fluepipes and other areas.
Rough-In: Installation of the drain, waste, vent, and supply lines in a structure to the proposed location of each fixture.
Sanitary Fitting: Fitting that joins the assorted pipes in a drain, waste and vent system; designed to allow solid material to pass through without clogging.
Sanitary Sewer: House drain that carries wastewater away from the house to a sewer system or septic tank.
Self-Rimming Sink: Sink with no metal ring that has a built-in lip of the same material that supports it in the vanity top.
Service Entrance: Pipe connecting the water company piping to the water meter.
Shroud: Color-matched component under a wall-mount lavatory that covers the drain outlet for aesthetic purposes.
Sleeve: Pipe passed through a wall for the purpose of inserting another pipe through it.
Soil Stack: Largest vertical drain line to which all branch waste lines connect; carries waste to the sewer line at the street.
Solder: Metal alloy melted to create a fused joint between metal pieces. Also the act of melting solder into the joint.
Spud: A threaded opening on the water heater tank. Also a tool for digging having characteristics of a shade and chisel.
Stack: The vertical main in the drain, waste, and vent system, extending one or more stories.
Stand Pipe: Open vertical pipe that receives water from a washing machine. Also the vertical pipe run supplying water to a fire sprinkler system; also a large vertical pipe into which water is pumped in order to produce a desired pressure; a high vertical pipe or reservoir that is used to secure a uniform pressure in a water-supply system.
Stop Valve: The shutoff valve under sinks and toilets. Allows water supply to be cut off to one fixture without affecting the water supply to other fixtures.
Sump: A pit or pool for draining, collecting, or storing water. A chamber that provides water to the pump.
Sweating: Slang term for soldering. Also formation of condensation on the outside of pipes or toilet tanks.
Tailpiece: Section of pipe that runs between a fixture outlet and the trap.
Tank: Fixture reservoir for flush water. On a conventional toilet, the ballcock, flush valve, and trip lever are installed in the tank. A tank lid closes the top tank opening.
Thermostatic Valve: Pressure-balancing shower mixing valve with automatic temperature control. When temperature or pressure fluctuations occur at the water inlets, a thermal actuator adjusts the hot and cold ratio to maintain the original temperature setting.
Trap: Curved section of drain line that prevents sewer odors from escaping into the atmosphere. All fixtures that have drains must have a “P” trap installed. A toilet is the only plumbing fixture with an “S” trap.
Trap Arm: The waste arm portion of a drainage trap.
Trap Dip: The U-bend portion of a drainage trap.
Trap Primer: A small feeder line connecting the cold water line directly to the drainage trap, which releases a small amount of water to the trap should it run dry to maintain the water seal.
Trap Seal: Height of water in a toilet bowl “at rest.” Creates a seal that prevents sewer gases from entering the home.
Trapway: Channel in a toilet that connects the bowl to the waste outlet.
Trip Lever: Flush handle and actuating arm on a toilet tank or the lever that opens and closes the drain on the bathtub waste and overflow.
Usable Storage: Percentage of hot water that can be drawn from a tank before the temperature drops to a point that it is no longer considered hot.
Vacuum Breaker: An anti-siphon device that prevents the backflow of contaminated water into the water supply system.
Valve Seat: The non-moving part of a valve.
Vent: A pipe that allows air into a drain system to balance the air pressure, preventing water in the traps from being siphoned off.
Vent Stack: Upper portion of the soil stack above the topmost fixture through which gases and odors escape.
Vitreous China: Ceramic materials fired at high temperature to form a non-porous body, having exposed surfaces coated with ceramic glaze fused to the body. Used to manufacture bathroom fixtures such as toilets, bidets, and lavatories.
Waste Arm: Drain extension pipe, usually to extend a sink drain into a wall.
Waste & Overflow: Drain assembly for a bathtub.