Homeowners Glossary of Plumbing Terms

Plumbing doesn’t have to be confusing. Whether you’re tackling a minor repair, planning a renovation, or want to understand what your plumber is talking about, this glossary explains the most common plumbing terms used across Canada. Each entry is written in plain language to help homeowners better understand their systems, spot issues early, and make confident maintenance decisions.

A

• ABS (acrylonitrile-butadiene-styrene): Black plastic pipe for DWV systems.
• Absolute pressure: Pressure measured above a perfect vacuum.
• Access panel: Removable cover to reach valves or concealed plumbing.
• Acid waste: Corrosive effluent requiring special piping and neutralization.
• Adaptor (adapter): Fitting that connects dissimilar pipes or threads.
• Aerator: Screen at faucet tip that mixes air to reduce splashing and flow.
• Air admittance valve (AAV): One-way vent that prevents trap siphonage.
• Air chamber: Short vertical pipe that cushions water hammer.
• Air gap: Open space preventing backflow into potable water.
• Angle seat valve: Compact shutoff used with fixtures/appliances.
• Angle stop (angle valve): 90° shutoff supplying a single fixture.
• ANSI: U.S. standards body referenced on some products in Canada.
• Anti-siphon valve: Prevents reverse flow by siphonage.
• Appliance (plumbing): Water-using device like a dishwasher or washer.
• Arrester (water-hammer arrester): Device that absorbs pressure spikes.
• ASSE: Publishes plumbing product/safety standards.
• ASTM: Sets pipe and fitting specifications.
• Auger (closet auger / drain snake): Flexible cable for clearing clogs.

B

• Backflow: Undesired reversal of water/contaminants into potable lines.
• Backflow preventer: Device that stops backflow into drinking water.
• Backwater valve (BWV): Stops sewage from backing up into a building.
• Ball check valve: One-way valve using a floating ball.
• Ball valve: Quarter-turn shutoff with a drilled ball.
• Ballcock (fill valve): Toilet tank valve that controls refill.
• Basin wrench: Pivoting wrench for faucet nuts in tight spaces.
• Bidet: Fixture for personal cleansing.
• Black water: Wastewater from toilets.
• Boiler: Heats water for hydronic heat or indirect domestic hot water.
• Booster pump: Raises low water pressure.
• Branch line: Pipe carrying water or waste from a main.
• Brass: Copper-zinc alloy for valves/fittings.
• BTU (British Thermal Unit): Heat energy measure for heaters/boilers.
• Bushing (reducing bushing): Reduces size between female and male threads.
• Building drain: Lowest horizontal sanitary drain inside a building.
• Building sewer: Piping from building drain to public sewer or septic.
• Butterfly valve: Quarter-turn disc valve for larger lines.
• Bypass: Alternate piping around equipment (meter, softener).

C

• Cast iron pipe: Heavy drain pipe common in older homes.
• CCTV inspection: Camera survey of drains/laterals.
• Check stop: Fixture shutoff at the supply connection.
• Check valve: Allows one-way flow only.
• Cleanout: Access fitting to clear blockages.
• Closet auger: Curved auger for toilet clogs.
• Closet bend: Quarter-bend fitting below a toilet.
• Closet flange (toilet flange): Secures toilet to floor and drain.
• Combination wye and 1/8 bend (combo): Smooth directional change in DWV.
• Compression fitting: Ferrule-and-nut seal on tubing.
• Condensate drain: Removes moisture from AC or condensing appliances.
• Copper pipe Type K, L, M: Grades by wall thickness.
• Coupling: Short fitting joining two same-size pipes.
• Cross-connection: Link between potable and non-potable systems.
• CSA Group: Publishes Canadian plumbing standards (e.g., B64).
• CPVC (chlorinated PVC): Plastic pressure pipe for hot/cold water.
• Curb stop: Municipal shutoff at property line.
• Curved trap (P-trap / S-trap): Water seal against sewer gases (P-trap standard).

D

• Damper: Air control plate in vents/ducts (combustion/appliance context).
• Diaphragm: Flexible membrane inside valves/pumps.
• Dip tube: Sends cold water to bottom of a tank water heater.
• Drain: Pipe/channel removing wastewater from fixtures.
• Drain tile system: Perforated pipe around foundations for groundwater.
• Drainage fixture unit (DFU): Sizing unit for drainage load.
• Drainage system: Network removing wastewater/sewage.
• Drain cleaning: Clearing blockages by auger, jetting, or chemicals.
• Drip leg (sediment trap): Collects debris in gas lines.
• Drop ear elbow: Elbow with “ears” to fasten to framing.
• Dual flush toilet: Two flush volumes to save water.
• DWV (drain, waste, vent): System that removes waste and vents gases.

E

• Ejector pump: Lifts sewage from lower levels to a higher drain.
• Elbow (ell): Direction change, typically 45° or 90°.
• Energy factor (EF): Water heater efficiency rating.
• Escutcheon: Decorative cover for pipe penetrations.
• Expansion joint: Flexible connector for thermal movement.
• Expansion tank: Absorbs pressure from heated water.
• Epoxy pipe lining: Resin coating to restore leaking/corroded pipe.

F

• Faucet (tap): Fixture controlling water flow.
• Fall (pitch, slope): Downward angle for drainage.
• Ferrule: Compression ring sealing a joint.
• Fixture: Water-using/draining device (sink, toilet, shower).
• Fixture shutoff valve: Localized shutoff under a fixture.
• Fixture unit: Value used to size systems.
• Flapper: Rubber valve sealing a toilet’s flush valve.
• Flexible connector: Short flexible tube to fixtures/appliances.
• Float valve: Float-operated fill valve (toilets, tanks).
• Floor drain: Drain set in floors for water removal.
• Flow restrictor: Limits water flow in faucets/showers.
• Flushometer: Metered flush valve (commercial).
• Flux: Soldering paste for copper.
• Frost-free hose bibb: Outdoor faucet designed to resist freezing.

G

• Galvanized pipe: Zinc-coated steel in older homes.
• Garburator: Under-sink grinder for food scraps (Canadian term).
• Gasket: Flexible sealing material between surfaces.
• Gas cock: Manual gas shutoff valve.
• Gate valve: Sliding gate that fully opens/closes flow.
• Globe valve: Throttling valve with disk and seat.
• Gravity-operated toilet: Uses gravity to flush.
• Grease interceptor: Captures fats, oils, and grease.
• Grey water: Wastewater from tubs, showers, sinks, laundry.

H

• Hard water: High mineral content causing scale.
• Hose bibb (sillcock): Outdoor faucet for hoses.
• Hot water tank: Storage-type water heater.
• Hubless coupling / No-hub coupling: Rubber sleeve with band clamps for cast iron/plastic.
• Hydro jetting: High-pressure water drain cleaning.
• Hydronic heating: Hot water or steam heating through pipes.

I

• ID (inside diameter): Interior pipe measurement.
• Immersion heater: Electric element directly heating water.
• Indirect water heater: Tank heated by a boiler loop.
• Interceptor: Captures grease, sand, or oils before sewer.
• Insulation (pipe insulation): Wrap to reduce heat loss and freezing risk.
• Instantaneous water heater (tankless): Heats water on demand.
• Isolation valve: Shutoff for a fixture or piping section.

J

• J-bend: Part of a trap holding water to block gases.
• J-hook: Hook-style hanger supporting pipe.
• Jet pump: Shallow-well pump that uses a jet eductor.

K

• Kitchen sink strainer: Basket that keeps debris from drains.
• Kitec piping: Plastic-aluminum pipe used 1990s–2000s; known for failures.

L

• Lavatory: Bathroom sink.
• Lead: Metal once used in pipes/solder; now restricted.
• Leak detection: Locating hidden leaks using tools/tech.
• Liquid waste: Wastewater excluding solids.
• Loop vent: Vent loop tying back to a main vent.
• Laundry box: Recessed box with shutoffs and standpipe.
• Laundry tub (utility sink): Deep sink for laundry/clean-up.

M

• Main: Primary supply or drainage pipe.
• Manifold: Distribution hub, common with PEX.
• Mixing valve: Blends hot/cold for safe temperature.
• Moen cartridge: Replaceable faucet/valve cartridge.
• Mold: Fungus from moisture leaks/condensation.
• Municipal water supply: Treated water from a utility.

N

• Neutralizer: Reduces acidity in condensate/drains.
• New plumbing installation: Rough-in and finish for new work.
• Nipple: Short, double-threaded pipe.
• No-hub coupling: Flexible coupling with bands for hubless pipe.

O

• Offset: Direction change using angled fittings.
• O-ring: Round elastomer seal.
• OD (outside diameter): Exterior pipe measurement.
• Overflow tube: Toilet tank tube preventing overfilling.
• Oil interceptor: Captures oil before sewer (garages/shops).

P

• P-trap: Curved pipe under fixtures sealing against gases.
• PEX (cross-linked polyethylene): Flexible supply piping.
• Pipe dope (thread sealant): Compound for threaded joints.
• Pipe hanger: Support to secure/suspend piping.
• Pitch (slope): Downward grade for drains.
• Plumber’s putty: Soft sealant for fixture bases.
• Plumber’s tape (PTFE tape): Thread sealing tape.
• Plumbing snake: Flexible cable for clearing clogs.
• Poly-B (polybutylene): Grey plastic pipe used 1980s–90s; often replaced.
• Potable water: Safe for drinking/cooking.
• Pressure-balancing valve: Maintains shower temperature despite pressure changes.
• Pressure-reducing valve (PRV): Lowers incoming water pressure.
• Pump: Moves water (sumps, wells, sewage).
• P-trap primer: Adds water automatically to maintain trap seal.

Q

• Quarter-turn valve: Fully opens/closes with a 90° turn.
• Quick-connect fitting: Push-to-connect fitting for fast joins.

R

• Recirculation pump: Circulates hot water for quick delivery.
• Reducer: Joins different pipe sizes.
• Relief valve: Releases excess temperature/pressure.
• Re-piping: Replacing existing lines due to age/failure.
• Retaining nut: Secures stems, cartridges, or valves.
• Riser: Vertical supply pipe to upper floors.
• Rooter service: Professional mechanical drain clearing.
• Rough-in: Installing pipes before finishes.

S

• Sand interceptor: Traps sand/grit in drains.
• Sanitary tee: Tee with curved outlet to direct waste.
• Septic field (leaching bed): Disperses septic effluent into soil.
• Septic tank: On-site wastewater treatment tank.
• Service call: Standard diagnostic/visit fee.
• Service line: Pipe from municipal main to building.
• Shutoff valve: Stops water to a fixture/appliance.
• Slope (fall): Pipe angle for proper drainage.
• Soil stack: Vertical pipe carrying toilet waste.
• Stop-and-waste valve: Exterior shutoff with drain port.
• Sump pump: Removes water from a sump pit.
• Sweat fitting: Copper joint made by soldering.
• Sediment trap: Catches debris before appliances (gas).

T

• Tailpiece: Straight pipe between fixture outlet and trap.
• Tankless water heater: On-demand water heater.
• Tap: Common Canadian term for faucet.
• Temperature & pressure relief valve (T&P): Water-heater safety valve.
• Thermostatic mixing valve (TMV): Maintains safe outlet temperature.
• Trap: Curved pipe holding water to block gases.
• Trap arm: Pipe between trap and vent.
• Trap primer: Adds water to a trap automatically.
• Trap seal: Water retained in a trap to block gases.

U

• Union: Fitting that joins pipes but allows disconnection.
• Urinal: Wall-mounted fixture for liquid waste.
• Utility sink (laundry tub): Deep sink for cleaning/laundry.

V

• Valve: Device that starts/stops/regulates flow.
• Vent boot: Roof flashing around a vent penetration.
• Vent cap: Cover on vent to keep out rain/debris.
• Vent pipe: Allows air into drainage to balance pressure.
• Vent stack: Main vertical vent through the roof.
• Vertical lift pump: Moves water from lower to higher level.

W

• Waste arm: Horizontal pipe from trap to branch drain.
• Washer: Flat ring sealing faucets/valves.
• Water hammer: Shock/banging from sudden flow stop.
• Water main: Municipal pipe supplying neighbourhoods.
• Water meter: Measures water use for billing.
• Water softener: Removes hardness minerals.
• Wax ring: Seal between toilet base and flange.

Y

• Y-branch (wye): Joins a branch at about 45°.
• Yoke vent: Connects soil/waste stack to a vent stack.

Z

• Zone valve: Controls flow in hydronic heating zones.
• Zoning (plumbing/heating): Dividing a system into independently controlled sections.

Canadian Plumbing Standards & Codes

National Plumbing Code of Canada (NPC): Model code published by the National Research Council of Canada.
BC Plumbing Code: British Columbia’s adaptation of the NPC, enforced by BC Housing and Technical Safety BC.
Ontario Plumbing Code: Incorporated within the Ontario Building Code.
Alberta Plumbing Code: Province-specific adaptation of the NPC.
Quebec Construction Code – Plumbing Chapter: Quebec’s plumbing standards based on the NPC.
Manitoba, Saskatchewan, and Atlantic Provinces: Follow NPC with regional amendments.
Territorial Codes (Yukon, NWT, Nunavut): Adopt NPC directly.

Canadian Plumbing Associations & Trade Bodies

• Canadian Institute of Plumbing & Heating (CIPH): National organization representing manufacturers and suppliers.
• Mechanical Contractors Association of Canada (MCAC): Represents plumbing and mechanical contractors nationwide.
• Corporation of Master Pipe-Mechanics of Quebec (CMMTQ): Regulates licensed plumbing and mechanical contractors in Quebec.
• Mechanical Contractors Association of BC (MCABC): Represents mechanical and plumbing trades in British Columbia.
• Mechanical Contractors Association of Alberta (MCA): Supports contractors in Alberta’s plumbing and mechanical industries.
• Mechanical Contractors Association of Manitoba (MCAM): Represents mechanical contractors in Manitoba.
• Mechanical Contractors Association of Saskatchewan (MCAS): Represents mechanical trades in Saskatchewan.
• Ontario Plumbing Inspectors Association (OPIA): Association for plumbing inspectors across Ontario.
• United Association of Journeymen and Apprentices (UA Canada): Union representing plumbers, pipefitters, welders, and related trades.

Conclusion

Understanding your home’s plumbing helps you spot problems early and avoid costly damage. Keep exploring practical tips, maintenance guides, and service advice from Vernon Air Conditioning, Plumbing & Electrical Services: your trusted local experts for all things plumbing, heating, cooling, and electrical in the North Okanagan.