Our goal is to provide visitors with excellent plumbing how to's and other great plumbing-related articles.
Kitchen related articles Bathroom related articles Commercial related articles Misc articles Favorite links

Plumbing Terminology
Extensive Online Plumbing Dictionary

Click on any letter of the term you would like to find

B Tank:
Acetylene tank holding 40 cu. ft. of gas, used for plumbing, once used to fuel boat, thus the name.

Back Pressure:
Pressure that resists the flow of fluid in a piping system.

Back Siphonage:
The negative pressure that causes back flow.

Back Vent:
Plumbing fixture's separate vent in a building drainage system.

Back Wash:
The process of cleaning a filter by reversing the flow of water through it. Dirt is sent to waste.

Flashback of flame through the burner venturi casing the gas to burn at the orifice.

Back Flow:
When water traveling from one system backs into any part of the main distribution system, usually by siphoning.

Back Flow Preventer:
A device to prevent back flow, especially into a potable water supply. Required for sprinkler systems, handheld showers, pullout faucet spouts, and kitchen sprayers.

Whirlpool jets located on the fixture wall behind a reclining bather.

Backjet Pulse Canister:
A serviceable water-controlling device responsible for backjet pulsing action.

Back-To-Back Cartridge:
For use when you have two bathroom showers back to back. This cartridge keeps you from having to re-plumb your hot & cold supply lines in one of the showers.

Overflow of a plumbing fixture due to drain stoppage.

Backwater Valve:
Sewer line valve that prevents sewage from flowing back into the house.

An object placed in an appliance to change the direction of, or retard the flow of air, air-gas mixtures, or flue gases.

Balancing Valve:
A water heater valve that controls water flow and balances heat distribution to different locations.

Ball Check Valve:
A valve that uses a ball to seal against a seat to stop flow in one direction.

Ball Joint:
Spherical assembly allowing pivot rotations for many bathroom and shower accessories like showerheads.

Ball Passage:
This refers to the size of the ball that can pass through the trapway of a toilet. This also relates to trapway size. In general, the trap size will be 1/8" larger than the maximum size ball that can pass through it.

Ball Valve:
A valve that uses a ball to seal against the seat.

The fill valve that controls the flow of water from the water supply line into a gravity-operated toilet tank. It is controller by a float mechanism in the tank water. When the toilet is flushed, the float drops and opens the ballcock, releasing water into the bowl.

Balloon Bag:
Device that attaches to a garden hose & used to loosen blockage in a clogged drain.

Band Clamp:
A flexible band made of a variety of materials that has a cinching device used to secure pipes.

Band Hanger:
Type of pipe hanger that supports the pipe on a continuous strap of metal whose ends are joined at the top by a supporting rod. This rod bolts through the strap and is adjustable as to height.

Barlow's Formula:
An equation which shows the relationship of internal pressure to allowable stress, nominal thickness and diameter.

Relating to handicap access, e.g. a shower enclosure system having minimal or no bottom track and openings that are wheelchair-accessible.

A substance that releases hydroxyl ion when dissolved in water. Bases react with acids to form salt and water.

Compartment designed to hold water discharge.

Basin Wrench:
A wrench with a long handle with jaws mounted on a swivel that allows the jaws to reach and handle nuts to fasten faucets to a previously installed tank.

Basket Strainer:
Basket shaped strainer with holes and a slot that fits the kitchen sink drain allowing water to run out while catching food or other solids. Can also be closed to fill the sink with water.

Batch Feed:
Type of garbage disposer in which garbage is fed into unit one load at a time, then activated by placing a stopper into the drain opening.

Brushed Chrome.

Beam Clamp:
A device to attach a pipe hanger to an overhead I-beam. These may be malleable, carbon steel, or galvanized, and may be primed or painted.

Bed Depth:
The height of the ion exchange or filter media in the vessel after preparation for service.

Beehive Strainer:
A strainer inserted into a urinal to prevent foreign matter from falling into the drain.

Slang term in plumbing used to describe a low area or sag in a horizontal drain pipe causing a compromise of the correct angle of slope.

A colorless, aromatic liquid used to create plastics, rubber, resins and synthetic fabrics. A known carcinogen, benzene can lead to cancer and chromosome aberrations.

Bernoulli's Law:
The principle that a stream of liquid or gas exerts less sideways pressure while in motion than while at rest. As a result, fluids seem to be drawn into the steam, but are really pushed in by higher outside pressure.

Brake Horse Power. The actual amount of horsepower being consumed by a pump as measured on a dynamometer.

Bicarbonate Alkalinity:
Alkalinity of water due to the presence of bicarbonate ions.

A plumbing fixture similar in appearance to a toilet bowl used for personal hygiene. It is floor mounted, usually next to a toilet, and consists of a washing basin, faucet and sprayer.

Biochemical Oxygen Demand:
Amount of oxygen consumed in the oxidation of organic matter by biological action under standard test conditions; often used as a measure of the strength of sewage and waste water.

Subject to degradation to simpler substances by biological action, such as the bacterial breakdown of detergents, sewer wastes and other organic matter.

Black Oiled:
Term associated with pipe surface whereby material ordered in this manner is protected with a varnish-type oil on the O.D. for temporary corrosion protection during transit and in short-term storage.

Black Pipe:
Lacquer-finish cast iron pipe.

Wastewater from toilets or latrines and sinks used for food preparation or disposal, or for the disposal of chemicals.

To drain a pipe of excess air by opening a valve at the end of the pipe.

Blind Plug:
Plug used on no hub pipe.

Block Sensor Mode:
For touchless faucets, a system mode that occurs when the faucet continually senses an object, causing the faucet to stop functioning normally. The faucet will appear to be "OFF", and will self-actuate every two hours to alert you to its condition.

Blow Torch:
A torch used to solder pipes, activated by pressurized fuel and air to generate its flame.

A drain-cleaning device consisting of a rubber bladder with a hose fitting on one end and a nozzle on the other. The device attaches to a water hose and is inserted into a clogged drainpipe. As water is introduced, it expands to grip the pipe, and releases pulsating bursts of water through the nozzle, forcing water through the pipe to clear the obstruction.

Partial venting or draining, under pressure, of the water side of a boiler to reduce or remove unwanted contaminants. Also the pressure drops after releasing a pressure-relief valve.

Another name for a Blowbag.

Blown-Out Water Closet:

A flushing design using a non-siphoning trapway at the rear of the bowl, and an integral flushing rim, relying entirely on high water volume.

Brushed Nickel.

Shower component used in conjunction with a showerhead to deliver flow of water. It is commonly used in multiples to create a custom showering space.

A sealed tank where water is turned to steam for heating or power.

Boiler Feed:
A check valve controlling inlet water flow to a boiler.

Boiling Point:
The temperature at which liquid changes to vapor by the addition of heat.

The top portion of a compression valve assembly, it holds the valve in place as it is tightened against the valve seat at the other end of the assembly.

Water-containing receptor which receives liquid and solid body waste; two general bowl classifications are round front and elongated.

Internal (female) threaded end of pipe.

Box Flange:
Flange containing internal (female) threaded pipe fitting.

Brackish Water:
Water containing bacteria between 1,000 and 15,000 ppm of dissolved solids.

Braided Hose:
Flexible connecting hose

Any part of a drain system other than the main, riser, or stack.

Branch Vent:
A vent connecting one or more individual vents with a vent stack.

Slang for faucets and fittings regardless of materials used.

A strong solution of sodium chloride (salt) used in the regeneration of ion exchange water softeners.

British Thermal Unit - A unit of heat energy required to raise the temperature of 1lb. of water 1 degree Fahrenheit.

Drinking faucet with flow-regulated push-button self-closing valve. Also known as a "water fountain".

Buchan Trap:
An obsolete way of venting a waste water line. Consisted of an in-line trap with a vent opening located on the inlet side of the trap. The vent was then terminated above ground above the normal flood level.

Building Drain:
The lowest point in a drainage system where the interior drainage pipes meet and are conveyed it to the sewer.

Shelves or storage units recessed flush with surrounding walls.

A heat producing device where the flame or heat is produced.

Burst Pressure:
The internal pressure that will cause a piece of tubing to fail.

A pipe fitting threaded on the inside & out used to join two pipes of different sizes.

Butterfly Valve:
A serviceable valve that allows water to flow through it when open, and stops the water flow when closed.

The raised portion of a shower curb that is on more than one level.

BX Cable:
Metallic sheathed cable containing A/C electrical wiring. Typically used when wiring would otherwise be exposed.

Type of shower door that consists of two or more panels running in parallel tracks.