Plumbing Terminology

In able to completely understand your plumbing system it is essential that you are fully knowledgeable of all associated plumbing terms. Below you will find a glossary of plumbing terminology that you should familiarize yourself with. If we can assist you in any way, please contact Crown Plumbing Service us at 972-346-2332.

Acrylic: Acrylic is a thermoplastic used on the surface of bathtubs and whirlpools. Acrylic comes in sheets and is formed to the shape of the mold (tubs/showers) in the factory. Fiberglass is typically added to the back for strength.

ADAPTOR: An Adaptor is a fitting that joins two different types of pipes together.

AERATOR: An Aerator is a part at the end of a faucet spout that mixes air into the dropping water, therefore aerating the water.

AIR GAP: An air gap is an air-filled space that allows contaminated water to discharge freely, thus preventing the contaminated water from ever siphoning back into the water supply.

ANGLE STOP: An angle stop is an “emergency” stop (valve) that is usually installed before the water supply line 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 stop” is that the angle stop changes direction by 90 degrees while a straight stop is like most valves and does not change direction.

BASIN: A basin is a circular vessel with slopping or curving sides for holding water for washing.

BIDET: Bidet is pronounced B’Day and 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.

CENTERSET: A centerset is a style of bathroom lavatory faucet that has a combined spout and handles.

CONSOLE LAV: A console lav is a table-like fixture with an integral lavatory. The back is fixed to a wall and the front is supported by brackets.

COUPLING: A coupling is a fitting that joins two pieces of pipe together.

CPVC : Chlorinated PolyVinyl Chloride is a plastic product designed for drinking water at temperatures up to 180 degrees.

CWP: CWP is the abbreviation for cold working pressure.

CWT: CWT is the abbreviation for Copper Water Tube.

DIVERTER: A diverter is a valve that directs water to various outlets. They are used in showers, tub & shower combinations, bidets, Roman tub fillers and kitchen faucet sprayers.

DWV: DWV is the abbreviation for Drainage, Waste & Vent systems.

DYNAMIC PRESSURE: Dynamic pressure is the pressure when the water IS flowing.

ELBOW (aka ELL): An elbow is a fitting with two openings that change directions 90 degrees.

ELONGATED: Elongated is the shape of the front of a toilet bowl and is usually 2″ longer than the standard bowl.

ENAMEL: Enamel is an opaque vitreous composition that is applied by fusion to the surface of metal fixtures such as cast iron and pressed steel tubs, lavatories and sinks.

ESCUTCHEON: An escutcheon is a flange or shield beneath a faucet handle.

FHT: FHT is the abbreviation for female hose threads.

FIBERGLASS: Fiberglass is a specialized fibrous form that is used in making products such as boats and bathtubs.

FINISHES: The following finish abbreviations are generally used by many faucet manufacturers : BC Brushed Chrome BN Brushed Nickel CP Polished Chrome PB Polished Brass SN Satin Nickel WH White

FIP(s): FIP is the abbreviation for female pipe threads.

FIXTURE: Fixture is a 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.

GPF: GPF is the abbreviation for Gallons Per Flush.

GPH: GPH is the abbreviation for Gallons Per Hour.

GPM: GPM is the abbreviation for Gallons Per Minute.

HANDSHOWER: A handshower is a showerhead that is designed with a handle that is connected to a water supply by a flexible hose.

H.P.: H.P. is the abbreviation for “horse power.”

H.T.: H.T. is the abbreviation for “hose threads.”

I.D.: I.D. is the abbreviation for “inside diameter. In plumbing most pipes are sized by approximate I.D. which means that when plumbers say 3/4″ pipe it generally means that the outside diameter is wider than 3/4”.

IPS: IPS is the abbreviation for “iron pipe size.” Sometimes it means male pipe threads.

LAVATORY: A lavatory is fixed bowl or basin with running water and drainage for washing. Many people also use the word “Lavatory” as meaning a bathroom.

MHT: MHT is the abbreviation for male hose threads.

MINI-WIDESPREAD: Mini-Widespread is a special style of bathroom faucet that has a separate spout and handles but is also designed small enough that it will fit 4″ center-to-center faucet holes.

MIP(s): MIP(s) is the abbreviation for male pipe threads.

NPS: NPS is the abbreviation for National Pipe Straight Threads Standard

NPT: NPT is the abbreviation for National Pipe Tapered Threads Standard

OD: OD is the abbreviation for “outside diameter.”

OVALITY: Ovality is the difference between the most wide OD and the most narrow OD on a pipe or tube.

OEM: OEM is the abbreviation for Original Equipment Manufacturer

PEX: PEX is the abbreviation for Polyethylene Plastic Material

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″.

PR: PR is the abbreviation for “Pressure Regulator and usually means water pressure regulator.

PVD: PVD or Physical Vapor Deposition is a modern plating process that is used in faucet manufacturing. Unlike former days when polished brass would easily tarnish, however, polished brass finishes with PVD are extremely durable and won’t generally tarnish or discolor.

POP-UP ASSEMBLY: The pop-up assembly is the drain mechanism of a faucet that is installed on a lavatory.

PORCELAIN: Porcelain is white ceramic ware that consists of quartz, kalin, and feldspar. It is fired at high temperature on steel or cast iron to make the surface of bathtubs, kitchen sinks and bathroom lavatories.

PORCELAIN ENAMEL: Porcelain enamel is a Vitreous enamel that is often used on top of ceramic, or porcelain glaze on top of cast iron.

PRESSURE BALANCE VALVE: A Pressure Balance is a shower mixing valve that automatically maintains balance between hot and cold water supplies by regulating fluctuations in pressure.

REDUCER: A reducer is a fitting that connects pipes of different sizes together.

RISER: A riser is a vertical assembly of pipe and fittings that generally distributes water upward.

ROUND FRONT: Round front is the standard shape of the front of a toilet bowl and is usually 2” shorter than the optional “elongated” bowl.

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.

SDR: Standard Dimension Ratio (SDR) is used for determining the minimum wall thickness for pipe.

STATIC PRESSURE: Static Pressure The pressure when NO water is flowing.

STRAIGHT STOP: A straight stop is an “emergency” stop (valve) that is usually installed before the water supply line 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.

STREET ELBOW: A street elbow is an elbow fitting that has a male end on one side and a female end on the other side.

THERMOSTATIC VALVE: A thermostatic valve is a pressure balancing shower mixing valve with automatic temperature control.

TRAP: A trap is a curved section of drain line that prevents sewer odors from escaping into the atmosphere.

TUBES: Unlike pipes, the measurement of a tube (i.e. 2″) corresponds to its outside diameter (OD). So the outside diameter of a 2″ tube is truly 2″.

UNC, UC, or NC: UNC, UC or NC is the abbreviation for Unified National Coarse Thread

UNF, UF, or NF: UNF, UF or NF is the abbreviation for Unified National Fine Thread

VANITY: A vanity is a bathroom storage cabinet beneath the counter.

VITREOUS: Vitreous is a surface material on some plumbing fixtures that is derived from glass. It is low in porosity and is translucent.

WASTE & OVERFLOW: Waste and overflow is the drain assembly for a bathtub.

WATER CLOSET: A water closet is a Toilet.

WIDESPREAD: Widespread is a style of bathroom faucets that have a separate spout and handle.

WOG: WOG is the abbreviation for cold water, oil, gas pressure rating.