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Plumbing Dictionary

Plumbing, Kitchen & Bath Dictionary

An easy-to-use glossary of common plumbing terms and abbreviations



ABS
Generally, in the plumbing industry (it is used a lot in the auto industry because it is so durable) this is black colored plastic pipe and fittings used in drainage, sewer, waste and vents. ABS (Acrylonitrile Butadiene Styrene) pipe/fittings and also PVC (see below) plastics have replaced much of the cast iron, lead and steel pipes formerly used for DWV. Important note is that no solvent cement (and primer) can totally "glue" (solvent weld) ABS to PVC plastic. Under normal conditions, quality ABS (when virgin resins are used) will not crack, chip or peel.
ACCESS PANEL
An opening in the wall or ceiling near the fixture that allows access for servicing the plumbing system.
ACRYLIC
A thermoplastic used on the surface of bathtubs and whirlpools. Generally comes in sheets and is formed to the shape of the mold (tubs/showers) in the factory. Generally fiberglass is added to the back for strength.
ADA
Governmental guidelines. ADA stands for Americans with Disability Act. These guidelines do tend to change over time. When related to public plumbing, kitchen and bath the intent of the act/rules is to make restrooms, and other public sanitary facilities more easily accessible to those who have some disability such as being blind. Commercial restroom signs with braille are an example of products that we sell largely due to ADA rules.
ADAPTOR
A fitting that joins two different types of pipes together. Or/Also a fitting that joins threaded with none threaded pipe (as in: female adaptor or male adaptor, PVC to cast iron pipe).
AERATOR
A part at the end of a faucet spout which mixes air into the dropping water, thereby aerating the water.
AGA
Imprinted on many gas valves and appliances. It is the American Gas Association rating.
AIR ADMITTANCE VALVE
A mechanical one way valve used in place of traditional non mechanical (very reliable) vents. It is to allow air to enter waste piping and equalizing pressures. Vents are used to preserve the seal of trap in plumbing fixtures. Also known as auto trap vents.
AIR GAP
Air-filled space allowing contaminated water to discharge freely, preventing the contaminated water from ever siphoning back into the potable water supply.
ANGLE STOP
An "emergency" stop (valve) that is usually installed before the water supply line (below) to toilets and faucets. Angle stops are to be shut off in case of an emergency or repair and are generally not designed for daily on and off usage. The difference between a "straight stop" and an "angle stops" is that the "angle" stop changes direction by 90 degrees while a straight stop is like most valves and does not change direction.
ANODE ROD
Sacrificial rod used mainly in water heaters. It helps protect the lining of and generally lengthens the life of a water heater.
BACK FLUSH
To temporarily reverse the normal liquid flow through a plumbing system.
BALLCOCK
Also known as a float valve, the ballcock controls the flow of water into a gravity-operated toilet tank. When the toilet is flushed the float ball drops with the water level causing the ballcock to open, this allows water to reenter the tank. As the water level rises it lifts the float ball causing the ballcock to close once the tank is completely filled.
BALL PASSAGE
The ball passage indicates the size of a ball that can pass through a toilet's trapway. It also refers to the size of the trapway of a toilet; the trap size is to be 1/8" larger than the ball that can pass through it.
BASIN
Generally circular, vessel with slopping or curving sides for holding water for washing. Usually used to refer to a sink of some sort.
BASKET STRAINERS:
Generally a basket shaped strainer drain receptacle with holes, for sinks. Used to catch large food particles to prevent them from entering the drainage system.
BIBB
aka bibcock or hose bibb - typically a faucet with nozzle bent downward. Also called: outside/outdoor faucet/spigot or garden faucet.
BIDET
Pronounced B'Day, is a plumbing fixture similar to a toilet bowl (but no solids are to be deposited in a bidet) used for washing genitals and posterior areas of the body. It is floor mounted, usually next to a toilet, and incorporates a washing basin, faucet and sprayer. Bidets are very popular in some countries such as France and have finally been "discovered" in the U.S.. A bidet is commonly equipped with a hot and cold mixing valve to provide warm water for washing.
BISQUE
Refers to the finish on the unglazed areas of vitreous china fixtures.
BLACK WATER"
Waste water from toilets.
BTU
Abbreviation for "British Thermal Unit"; a measurement of heat equal to the amount of heat necessary to raise one pound of water one degree Fahrenheit at sea level. (One BTU is equal to about 250 calories.)
BUCHAN TRAP
Obsolete way of venting a waste water drain. An in-line trap with a vent on the inlet side. Also known as a Bristol interceptor.
CAST IRON
Formerly used for drainage, sewers, waste, and vent pipe and fittings. Very durable and heavy metal. Today, many top quality bath tubs are still made with cast iron. Pipes and fittings today are generally only used for commercial applications where fire ratings are involved.
CENTERSET
A style of bathroom lavatory faucet having combined spout and handles. Handles are 4" from center of handle-to-handle. Also a single handle faucet installed on 4" center-to-center faucet holes.
CHINA
In the plumbing industry that generally refers to porcelain or vitreous china used in making toilets and lavatory sinks. China is a material that is made from clay and is glazed and high fired in a kiln. The finish is very hard and smooth. An excellent product for toilets and lavatories. Fire clay is another form of china that is used for large farm sinks.
CIRCUIT VENT
Where one common vent serves up to a maximum of eight fixtures connected to a horizontal branch drain. Circuit venting must be designed by a professional engineer. The vent must be installed between the two most upstream fixture drains and the vent cannot receive the discharge of any waste or soil.
CLEANOUT
A plug in a drain pipe, vent or trap that provides access for the purpose of clearing an obstruction.
CLOSE-COUPLED TOILET
A two-piece toilet. The toilet tank is separate from the toilet bowl. This is the most common type of toilet.
CLOSET
Generally means "water closet" (aka: toilet). A closet auger is a toilet auger which is used to clear toilet stoppages.
CLOSET AUGER
A flexible rod with a curved end used to access the toilet's built-in trap and remove clogs.
CLOSET BEND
A curved fitting that connects the closet flange to the toilet drain.
CLOSET FLANGE
An anchoring ring secured to the floor.The base of the toilet is secured to this ring with bolts.
C/O
Cleanout
COMMODE
Generally also stands for toilet.
CONSOLE LAV
A table-like fixture with an integral lavatory. The back is fixed to a wall and the front is supported by consoles (brackets) or legs.
COPPER
Reddish-brown, non-ferrous metal widely used for household plumbing pipes.
COUPLING
A fitting that joins two pieces of pipe (or other fittings) together.
CPVC
Chlorinated PolyVinyl Chloride is a plastic product designed for drinking water at temperatures up to 180 degrees (where code permits). Comes in straight or rolls, generally off white colored (orange for fire sprinklers).
CW
Abbreviation for Cold Water
CWP
Abbreviation for Cold Working Pressure
CWT
Abbreviation for Copper Water Tube (refers to nominal pipe size).
CxC
Copper x copper, meaning the fitting is sized for copper pipe.
CYCLE TIME
Refers to the amount of time it takes a toilet to complete it's flush cycle, from the instant it is flushed until the water supply shuts off.
DAM
Refers to the seal caused by water in a trapway.
DIVERTER
Valves which direct water to various outlets. They are used in showers, tub & shower combinations, bidets, Roman tub fillers and kitchen faucet sprayers.
DOUBLE VENT
See Relief Vent
DRAIN
Drainage inside the building, note that "sewer" is outside the building.
DWV
Abbreviation for Drainage, Waste & Vent systems. Not for drinking water.
DYNAMIC PRESSURE
The pressure when the water IS flowing.
EFFLUENT
Liquid waste, potentially hazardous, generally refers to liquid waste from septic tanks.
ELBOW (aka ELL):
A fitting with two openings that changes the direction of the line. Also called an ell. It comes in a variety of angles, from 22 1/2° to 90°, though by far the most common is the 90°.
ELONGATED
The shape of the front of a toilet bowl. Generally about 2" longer than the standard "round front" bowl.
ENAMEL
An opaque vitreous composition applied by fusion to the surface of metal fixtures such as cast iron and pressed steel tubs, lavatories and sinks. Please do not confuse enameled steel with enameled cast iron. Cast iron with enameling is much more durable.
ESCUTCHEON
(pronounced ih-skuhch-uhn) An ornamental or protective flange or shield beneath a faucet handle, This part covers the faucet stem and the hole in the fixture or wall. They are also found around shower arms, stop valves, and other piping that comes through the wall. Typically cosmetic, some escutcheons are gasketed to help with waterproofing, like escutcheons for body sprays.
FALL
The proper slope or pitch of a pipe for adequate drainage.
FERNCO
A manufacturer. Commonly means rubber coupling
FHT
Abbreviation for female hose threads.
FIBERGLASS
Glass in a fibrous form used in making products such as boats and bathtubs.
FINISHES
The following finish abbreviations are generally used by many (not all) faucet manufacturers :
BC Brushed Chrome
BN Brushed Nickel
CP Polished Chrome
PB Polished Brass
SN Satin Nickel
WH White
FIP(S)
Abbreviation for female iron pipe size threaded fitting. Threads are inside the fitting.
FITTING
A part used to join two sections of pipe or other fittings together. An example of a fitting is an elbow, bushing, or coupling.
FIXTURE
Broad term in plumbing/kitchen/bath that could be an entire toilet, sink, tub, etc OR it could be the devices that provide a supply of water.
FLAPPER
Part of the flush valve that seals water inside the toilet tank or allows passage of water into the toilet bowl during the flush cycle. Also known as a flush ball.
FLOAT BALL
Connected to the ballcock inside the toilet tank. The float ball rises and falls with the water levels causing the ballcock to open and close.
FLUSHOMETER
A toilet valve that delivers water and then shuts off after it meters a certain amount of water.
FLUX
The paste that is used in soldering metal joints. Flux aids the process by preventing oxidation of the joint.
FNPT
Abbreviation for Female National Pipe Thread Taper.
FRICTION LOSS:
Pressure lost in a pipe due to turbulence created by water traveling through pipe.
FSWT
Female sweat connection
FVIR
Flammable Vapor Ignition Resistant. Gas fired water heaters sold as of July 1, 2003, per the American National Standards Institute (ANSI), must include features to resist possible ignition of flammable vapors outside of the water heater combustion chamber.
GAS COCK
Gas valve.
GPF
Gallons Per Flush. Today's toilets, per federal law, are only allowed to deliver 1.6gpf or less. In many years past, toilets flushed as much as 7-8gpf.
GPH
Abbreviation for Gallons Per Hour.
GPM
Abbreviation for Gallons Per Minute.
GRAY WATER
Waste water from all fixtures except toilets.
HANDSHOWER
A showerhead designed with a handle that is connected to a water supply via a flexible hose.
HEAD
The water pressure exerted by gravity (2.31 feet of height means/delivers one pound of head). Also, slang for toilet.
HOSE BIBB:
A garden or outdoor faucet. Also, a faucet that delivers water with a hose connection at the end of the spout (such as to a washing machine).
HOUDEE
Former manufacturer. Commonly means stainless steel sink frame.
H.P.
Abbreviation for "horse power."
H.T.
Abbreviation for "hose threads." Garden hose threads are different than standard pipe threads. They are much more coarse and are 0.75 - 11.5 NH (normal hose). The 0.75 is the nominal diameter (3/4 inch) and the 11.5 is the number of threads per inch.
HW
Hot water
I.D.
Abbreviation for "inside diameter." In plumbing, most pipes are sized by "nominal" (approx.) I.D. which means that when plumbers say 3/4" pipe, for example, it generally means that the outside diameter is wider than 3/4".
IPS
Generally an abbreviation for "iron pipe size." Sometimes it means male pipe threads.
IPT
Generally an abbreviation for "iron pipe thread." Sometimes it means male pipe threads.
LAVATORY ("LAV")
A fixed bowl or basin with running water and drainage for washing. Many use the word "lavatory" as meaning a bathroom.
LWCO
Low water cut off.
MALE THREADS
Male threads thread into female threads. Female fittings openings are larger than male fittings. Male fittings fit into/inside female fittings.
MHT
Abbreviation for male hose threads.
MINI-WIDESPREAD
A special style of bathroom lavatory faucet having separate spout and handles. But designed small enough that it will fit 4" center-to-center faucet holes.
MIP(s)
Abbreviation for male pipe threads.

NOMINAL
Size used for identification only; not literal dimensions. Used to identify pipe and fitting sizes in plumbing. Refers to the inside diameter of the pipe which can vary by thickness of the pipe. The outside is a constant size. For copper pipe the outside diameter is always 1/8" larger than the nominal size. Example: 1/2" nominal is always 5/8" O.D.
NPS
Abbreviation for National Pipe Straight Threads Standard (IPS)
NPSM
Abbreviation for National Pipe Straight Mechanical. Similar to garden hose threads NPSM fittings must be used with a washer between the male and female fittings to create a tight leak-proof seal. The threads themselves will not seal liquid from leaking at the fitting.
NPT
Abbreviation for National Pipe Tapered Threads Standard (FIP, MIP). NPT is the United States standard for tapered threaded fittings and pipe. Manufacturers are to follow this standard when fabricating or manufacturing pipes and fittings used for plumbing.
OD
Abbreviation for "outside diameter." The measurement of the diameter of the pipe as taken from the outside edge.
OEM
Abbreviation for "original equipment manufacturer."
ONE-PIECE TOILET
The toilet tank and bowl are not separate, but make one single fixture. Less common and usually more expensive, but generally a more stylish toilet.
OVALITY
The difference between the most wide OD and the most narrow OD on a pipe or tube. Found be subtracting the minimum outside diameter from the maximum outside diameter on a pipe.
OVERFLOW TUBE
If the ballcock malfunctions this vertical tube inside the toilet tank will direct water into the toilet bowl. This is the part that can sometimes make your toilet sound like it is constantly running, which is an indication that there is a problem with your ballcock.
PB
Polybutylene, flexible plastic tubing formerly used in water supply systems where allowed by code.
Common finish abbreviation for polished brass when referring to a fixture's part number
PE
Abbreviation for polyethylene. Most common plastic made. Plastic used for many types of water and gas piping.
PEX
Abbreviation for crosslinked polyethylene. A plastic material manufactured with chemical crosslinks (stronger than, PE.)
PIPES
Unlike tubes, the measurement of a pipe (i.e. 2") roughly references the inside diameter (ID) of the pipe and not the outside diameter (OD). A 2" Sch 40 pipe actually has an OD of 2.375", a wall thickness of .154" and an ID of 2.067".
PLUMBER'S PUTTY
A pliable putty used to seal joints.
POC
Point of connection
POP-UP ASSEMBLY
The drain mechanism of a faucet installed on a lavatory. The drain stopper "pops" up and down.
PORCELAIN
A white ceramic ware that consists of quartz, kaolin, and feldspar. It is fired at high temperature on steel or cast iron to make the surface of some bathtubs, kitchen sinks and bathroom lavatories. Many times the word "porcelain" also refers to porcelain china which is a ceramic product with porcelain glaze.
PORCELAIN ENAMEL
Vitreous enamel. Many times the words "porcelain enamel" refers to pressed steel (not recommended by us) products with a porcelain glaze. When purchasing "fixtures" we like to recommend either a porcelain glaze on top of ceramic, or porcelain glaze on top of cast iron.
POTABLE
In reference to water is that "potable" means it is drinkable water. Water that is suitable for human consumption.
POWER VENT
Refers to mechanical venting in water heating. Generally (not always) water heaters that use power venting are more efficient than regular draft venting.
PR
Abbreviation for "Pressure Regulator." Generally means water pressure regulator. Most codes require one if water pressures ever exceeds 80 pounds at any time on domestic potable water systems inside a structure.
PRESSURE BALANCE VALVE
A shower mixing valve that automatically maintains balance between hot and cold water supplies by immediately regulating fluctuations in pressure. As a result the outlet temperature remains constant.
PRIMING JET
The opening in the toilet bowl that allows the flow of water from the tank, designed to push waste through the trapway.
PRV
Pressure reducing valve.
PULL OUT SPRAY
When referring to a kitchen faucet this is a retractable hose/sprayhead. We'd like to mention that hoses used with a pull-out spray can turn out to be a high replaceable item. If you have a pull out sprayer be sure to pull it out straight each and every time. Do not kink the hose because if you do, no matter what brand, you could be ordering replacement hoses frequently.
PVC
Polyvinyl Chloride - A rigid, generally white plastic pipe. Used for waste and vent systems as well as cold water (underground) supplies outside of the house as well as used for sprinkler and irrigation pipes, sewers, drains, wastes and venting pipes and fittings. Flexible PVC pipe is also available and quite practical for spas, pools and sprinklers. PVC in the plumbing business is generally white but sometimes comes in other colors (in our industry gray is the second most popular PVC color).
PVD
Physical Vapor Deposition (used mostly with polished brass or gold finishes). This is a modern plating process used in faucet manufacturing. Vaporized zirconium reacts with nitrogen and other gases to form a VERY durable plated surface. Unlike former days when polished brass would easily tarnish over time, polished brass finishes with PVD are extremely durable and won't generally tarnish or discolor.
REDUCER
A fitting that connects pipes of different sizes together.
REFILL TUBE
Carries water from the ballcock to the overflow tube after the siphon break in order to refill the toilet bowl.
RELIEF VENT
Extra vent added to a vent line or drain line to keep the air pressure within the system in balance with the outside atmosphere. This will help keep the traps from air-locking or losing their trap seal. Required when a drainage stack extends 10 or more stories above the building drain. Such drainage stack shall be served by a parallel vent stack that connects to the drainage stack at each fifth floor. Relief vents of these types of drainage stacks shall not be less in diameter than either the drainage or vent stack, whichever is smaller. Also required when combination waste and vent systems are used for multiple floor or shower drains, floor sinks in markets, work tables in schools or similar applications where the fixtures are not close enough to walls to allow for conventional type venting. Relief vents for combination waste and vents shall not be less than one-half of the inside cross sectional area of the drain pipe it will serve.
RIM HOLES
Small holes along the underside of the toilet bowl rim in which water flows out of, resulting in a rinsing of the toilet bowl's inner surface.
RISER
A vertical assembly of pipe and fittings that generally distributes water upward.
ROUGH-IN
The portion of a plumbing installation that includes running the water supply lines and drain, waste & vent lines to the proposed location of each fixture.
ROUGH-IN DIMENSIONS
Rough-in dimensions give you the necessary information to install basic plumbing, electrical venting or other similar systems before installing the fixture. Many times a dimensional drawing is available that provides this information.
ROUND FRONT
The standard shape of the front of a toilet bowl. Generally bout 2" shorter than the optional "elongated" bowl.
RUN
A complete or secondary section(s) of pipe that extend from supply to fixture or drain to stack.
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.
SCHEDULE (SCH)
The "Schedule" designation tells you how thick the wall is for any size of pipe with the higher schedule numbers meaning a thicker wall. The most common schedules are Sch 40 and Sch 80, but the actual wall thickness varies depending on the size of the pipe.
SIPHONING
Suction that takes place when water pressure drops which causes water or waste to be pulled through a descending outlet channel.
SIPHON BREAK
Recognized by the gurgling sound that takes place at the end of a toilet flush, the siphon break is when air is re-introduced into the trapway, causing the siphoning action to cease.
SDR
Standard Dimension Ratio (SDR) used for determining the minimum wall thickness for pipe. SDR is found by dividing the outside diameter (OD) of the pipe by the wall thickness measurement. To find the minimum wall thickness of a pipe you simply divide the OD by the SDR.
SEWER
Drainage outside the building. Note that "drain" is inside the building.
SOIL STACK
Largest vertical drain line to which all branch waste lines connect; carries waste to the sewer line.
SOLDER
A metal alloy that is melted to join or mend metal surfaces; also, the act of melting solder into the joint.
SPIGOT
Term used with PVC, CPVC and cast-iron fittings and pipe. For PVC or CPVC fittings and pipe; A male end of a fitting the same size as the pipe that is inserted and glued into the slip (hub) end of a fitting. For cast-iron pipe; The plain end of a cast-iron pipe. The spigot is inserted into the bell or hub (female) end of the next pipe to make a water tight joint.
SPxS
An abbreviation normally used for PVC or CPVC fittings, to describe a non-threaded fitting with a spigot end (male) on one side and a slip (female) connector on the other side. The spigot end is the same size as the pipe and glues into a slip fitting. The slip fitting is a normal female hub end that fits over pipe.
STATIC PRESSURE
The pressure when NO water is flowing.
STOP VALVE
A valve that controls the flow of water to an individual fixture, allowing water supply to be stopped to one fixture without affecting the water supply to other fixtures.
STRAIGHT STOP
An "emergency" stop (valve) that is usually installed before the water supply line (below) to toilets and faucets. Angle stops are to be shut off in case of an emergency or repair and are generally not designed for daily on and off usage. The difference between a "straight stop" and an "angle stops" is that the "angle" stop changes direction by 90 degrees while a straight stop is like most valves and does not change direction.
STREET ELBOW
An elbow (90 degree bend) fitting that has a male end (same size as pipe) on one side and a female end (pipe fits inside this size) on the other side.
T-BOLT
Also known as toilet or closet bolts, T-bolts are 2 anchor bolts that attach a toilet to the floor.
TAILPIECE
The section of drain fitting that protrudes into the trap.
TANK
Holds flush water for your fixture. On typical toilets the tank includes the ballcock, trip valve and flush lever.
TANK BALL
The moving part of the flush valve that seals water in or allows water out of the tank during the flush cycle. Also known as the flapper, flush ball, stopper and seal disk.
TANK BOLTS
Three bolts that hold together the tank, gasket and bowl of the toilet.
TANK COVER LOCK
Device to prevent damage to and removal of the toilet tank cover and contents of the tank.
TAP
Tap is synonymous with faucet. Also tap refers to the divergence of water from one fitting to another.
TEE
Any T-shaped plumbing fitting. It has three openings used to create branch lines.
TEFLON TAPE
Thread sealing tape with stain resistant, water repellant Teflon finish. Teflon is a trademark of DuPont.
TEMPERED
A heat treatment technique to strengthen and harden glass for more safety. Also applies to water that has been mixed in order to avoid a temperature extreme.
THERMOSTATIC VALVE
A 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.
THREAD SEALANT (LIQUID)
Provides a water seal in threaded connections.
THREAD SEALANT (TAPE)
Dry ribbons of sealant sold on spools. Unlike liquid sealant there is no chance of it getting into the supply lines and blocking water flow.
THROUGH-THE-FLOOR
Installation where the bath drain tee outlet points down rather than horizontal.
THUMB NUT
To ease installation and to prevent over-tightening this nut was designed to be tightened without tools.
THUMB SCREW
To ease installation and to prevent over-tightening this screw was designed to be tightened without tools.
TILE-IN
Installation where the sink is fit flush with the countertop
TOILET SETTING COMPOUND
Provides a non-hardening watertight seal for the base of the toilet and the floor.
TORQUE WRENCH
Tool for measuring the amount of force applied to a threaded connection
TPI
Threads per inch.
TRANSFER VALVE
Valve the changes the flow of water from one outlet to another
TRAP
A curved section of drain line designed to hold water thus preventing sewer odors from escaping into a building. All "fixtures" that have drains must have a "P" trap installed. A toilet is the only plumbing fixture that has an "S" trap instead of a "P" trap.
TRAP SEAL
The seal caused by water in a trap preventing septic gasses from leaking back into the home. The trap seal is measured from the inlet of the trap to the top of the dam.
TRAPWAY
Trap built into a toilet connecting the bowl to the waste outlet where siphoning occurs.
TRIP ARM
The trip lever on the outside of the toilet tank connects to this
TRIP CHAIN
Chain that connects the toilet trip arm and the flapper on the flush valve
TRIP LEVER
Handle attached to the outside of the toilet tank used to initiate the flush
TUBE
Unlike pipes, the measurement of a tube (i.e. 2") corresponds to it's outside diameter (OD). So the outside diameter of a 2" tube is truly 2".
TWO-PIECE TOILET
The toilet tank is separate from the toilet bowl. This is the most common type of toilet and is also called a close-coupled toilet.
ULF
Abbreviation for ultra low flush, which describes a toilet that deliver 1.6gpf or less.
UNC, UC, or NC
Abbreviation for Unified National Coarse Thread (National Coarse) - Use on fittings, nuts, & bolts - not for pipes.
UNF, UF, or NF
Abbreviation for Unified National Fine Thread (National Fine) - Use on fittings, nuts, & bolts - not for pipes.
UNION
Fitting that joins two sections of pipe, that allows them to be disconnected without cutting the pipe. Used primarily with steel pipes, but never in a DWV system.
VANITY
A bathroom storage cabinet beneath the counter. Some plumbers also call a lavatory sink a vanity. Often a mirror is on the wall above.
VENT
When referring to plumbing fixtures, all fixtures (sinks, etc) must have a vent. Vents are used to allow air into the drainage systems to prevent P traps to from being siphoned dry.
VENT STACK
The upper portion of the soil stack above the topmost fixture through which gases and odors escape.
VITREOUS
A surface material on some plumbing fixtures derived from or consisting of glass. It is low in porosity and is translucent. Generally porcelain china is vitreous china.
VTR
Vent through the roof
WASTE & OVERFLOW
The drain assembly for a bathtub. The outlet at the top removes the "overflow" water during tub filling and the drain at the bottom removes "waste" water when the tub is drained.
WASTE SHOE
Generally refers to a bathtub drain assembly.
WATER CLOSET (W.C.)
Another term for toilet. Many in our industry will write w.c. on drawings or quotes which means water closet (aka: "toilet").
WATER HAMMER
Shock waves in plumbing generally due to high velocity water being shut off quickly. This is mainly caused by under sizing of pipes and faucets or valves that are shut off fast. Sometimes installing water hammer arrestors can help alleviate or lessen water hammer. Best is to increase water pipe sizes (thereby slowing velocity).
W.C.
Water closet - aka: toilet
WET VENT
When the drain discharge of one fixture is put into the vent stack of another fixture. Vertical wet venting is the most common and allows 4 fixtures of one or two fixture units each to discharge (drain) into a vent pipe serving another fixture. This can only be done if all of the fixtures involved are located on the same story as the wet vented fixture.
WHITE - EURO
Not all whites are alike. Euro-white generally is a somewhat yellowish white. Similar to Corian and Avonite's = Cameo white; Surell/Formica and Wilsonart's = Frosty white.
WHITE - POLAR
Polar-white generally is a bluish white. Similar to Kohler, Elkay, Moenstone, and Swanstone's = White; Corian's = Glacier white; Avonite's = Porcelain white; Surrell/Formica's = Arctic white.
WIDESPREAD
A style of bathroom lavatory faucet having separate spout and handles. Usually 8" from center of handle-to-handle. Some widespread faucets can be set with handles up to 12" apart.
WOG
Abbreviation for cold water, oil, gas pressure rating (water oil gas).
WORKING PRESSURE
Normal, maximum operating pressure design of a faucet, valve or plumbing product.
WYE
A Y-shaped fitting with three openings used to create branch lines.

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