Bathroom terminology can hurt your noggin (Your head, not the horizontal reinforcing timber fixed among vertical studs in a stud partition wall, also known as a noggin.)
We’ve created your ultimate DIY and budding professionals’ guide to vocabulary used for plumbing, fixtures, and processes in bathrooms builds across the UK.
Learning the correct term for the task at hand will save you a headache at the supply store. Using the appropriate bathroom fittings terminology will also help you find professional-grade tutorials that don’t dumb down your question, as some entry-level guides can.
Let’s get started with the A to Z for bathroom installation
A
ABS – A strong and rigid plastic material that combines the best qualities of Acrylics, Butyrate and Styrenes. It’s primarily used in shower trays due to its durability.
Acrylic – A plastic material commonly used in baths. It is easy to mould, highly durable, and it stays warm to the touch.
Airlock – A blockage in a pipe caused by a trapped air bubble.
Asymmetrical basins – Several bathroom basins are asymmetrical or offset. Therefore, when you look at them from above, they’re not symmetrical. The bowl of the basin is off to one side, and there’s a small shelf or tap seating on the opposite side. The unit might also incorporate a drawer or towel rail sometimes.
B
Back-siphoning – A potentially hazardous situation in which water flows back into the main water system, e.g. from a hose, toilet or shower.
Back to wall toilet – A floor-mounted toilet in which only the pan is visible. The cistern is usually hidden behind a wall or unit.
Back to wall unit – A furniture unit used to hide a cistern for a back to wall toilet.
Ball cock or Float valve – This valve controls the flow of water into a cistern or tank. The valve is operated by a ball which floats on top of the water’s surface; when the water reaches a certain level, then the flow is shut off.
Ball valve – A type of quarter-turn valve that uses a pivoting, hollow ball to open or close flow through a pipe.
Bar – A unit of measurement for water pressure. 1 bar equals the force required to push water up to a height of 10 metres. For example, to push water 1 metre requires 0.1 bar of pressure.
Base coat – A flat coat of paint over which a layer of glaze is applied.
Bath and Shower Mixer – A single tap fitting with hot and cold inlet. It mixes the water in the body of the tap. It has got a spout into the bath tub, as well as a shower head with a valve which switches between the shower head and the tap spout.
Bath Filler Tap – A tap that mixes hot and cold water through a spout into the bath tub. That allows you to fill the bath to an ideal temperature from one tap fitting. It might have either one inlet hole and mix the hot and cold supply under the bath, or two separate ones – one hot and one cold and mix them in the tap. They are advertised as a one-tap or two-tap hole option accordingly.
Bath Tub – Baths can be made of ceramic, acrylic, enamelled steel, and sometimes stone or even wood. The bath tub itself may vary in size, although standard lengths are 1700mm 1600mm and 1500mm. Normal widths are between 700mm and 800mm. Again, however, this may vary depending on the design. Corner offset baths are also available and might fit into small or odd shaped rooms even better than into a bath of a conventional size or shape.
Batten – A narrow strip of wood, usually fixed to the floor or a wall to act as a support for a shelving or unit.
Bevel – Any angle where two pieces of wood meet at, other than a right angle.
Bidet – Although it resembles a toilet pan, a bidet is actually designed for washing intimate parts of the body. However, it can also be used for other purposes, such as washing feet.
Bi-Fold Door – A door or screen that folds in half to open, and oftentimes slides to one side. The term is used for both shower screens and shower doors.
Body jets – Small shower heads that are usually set into a wall, and are designed to spray the body instead of an overhead shower.
Bore – The hollow part of a pipe.
Bottle trap – A type of trap used with basins. The bottom part can normally be removed for maintenance or cleaning.
Brassware – A term for taps and wastes. While the finish is usually chromed, the interior is often made of brass as it can be precision engineered and won’t corrode when wet.
BTU (British Thermal Unit) – The heating output required to heat a room of a particular size. It can be worked out using the following equation: Room height x room width x room length (in feet & inches) = Total x 5 = BTU
Butt joint – A simple joint in which two pieces of wood are fixed together without any interlocking parts cut in them.
C
Cam and stud fixing – A simple fixing used in flat-pack construction.
Cap-nut – This is a nut used to tighten a fitting into a pipework.
Cavity wall – This is a wall made of two parallel masonry skins with an air space between them.
Ceramic disc technology – Used in taps, today a ceramic disc is used instead of old-style washers. It only needs a quarter turn of a handle in order to turn the water flow on or off.
Chamfer – A flat, narrow surface along the edge of a work-piece. It is usually at a 45⁰ angle to any adjacent surfaces.
Chase – A groove cut in masonry or plaster for electrical cabling or pipework.
Chrome plating or Chromium plating – A technique of electroplating a thin layer of chromium onto a metal object to help prevent corrosion and improve both maintenance and appearance.
Cistern – Usually found as part of a toilet, the cistern is a container made to hold water at atmospheric pressure and used for the flushing system. It’s commonly fitted with a float operated valve.
Close coupled toilet – The most common type of toilet in the United Kingdom, where the cistern is placed directly above the pan.
Cold water storage tank or Header tank – Usually found in the loft, it is a tank for holding water feeding into a home water system.
Combination boiler or Combi boiler – This is a combined central heating and water heating unit used in houses. It does not store hot water, but it heats water when and as required directly from the cold-water supply.
Comfort Height Pan – A term for a toilet that has a slightly higher pan, which makes the use of the toilet slightly easier for people with mobility issues.
Concealed cistern – A toilet cistern that is designed to be used with a wall-hung or back to wall toilet, hidden behind a wall or unit.
Contemporary – This is a style of interior decorating that includes the latest styles and trends to give a fashionable look.
Corner Bath – Corner baths come in different sizes and are mainly used to give a full-sized tub while taking up less wall length. They’re perfect for bathing children, and give a good base for using a shower over the bath. Standard sizes are 1500mm x 1500mm, 1200mm x 1200mm, or 1050mm x 1050mm, although other sizes are available. It is, therefore, worth shopping around to find one that suits best with your room plan.
Counterbore – A tapered recess that let the head of a screw or bolt lie below a surface.
Countersink – To cut a tapered recess that lets the head of a screw or bolt lie flush with a surface.
Counter top basin – A counter top basin is a freestanding basin sitting on top of a counter top or vanity unit.
Cup – To bend as a result of shrinkage. It is mostly referred to as across the length of a piece of wood.
D
Damp-proof course (DPC) – A layer of impervious material which prevents moisture from rising through a floor or in a wall.
Digital Shower – The particular type of shower gives you the opportunity to pick your ideal temperature of water. At the touch of a button, the shower will mix hot and cold water at the right amount to supply water at the correct temperature.
Double ended bath – A bath in which the taps are situated on one side.
Drain-waste-vent (DWV) system – Plumbing that removes waste water and sewage from a building, while also regulating air pressure within the pipes.
Dual flush – A toilet cistern that gives two options of flashing: a smaller, water-saving flush or a full flush. These flushes are usually 3 and 6 litres in volume respectively.
E
Earth – A connection between the ground and an electrical circuit. It’s also a terminal where this connection is made.
Earth bonding –All metal parts in a plumbing system have to be connected to the ground to prevent any electrical conduction, as required by law. This can be achieved with the use of an earth-bonding strap.
Electric Shower – An electric shower takes water from the cold supply and heats it on demand when you turn it on. The greater the wattage of your shower the better the flow of hot water that you can expect.
Electrical heating element – It is used in electric showers to heat water while flowing through the unit.
Enclosures – The term refers to shower screens and cubicles. This typically encapsulates the shower, allowing you to keep as much water as you want within the enclosure and preventing it from soaking the rest of the room. An enclosure usually sits on top of a shower tray.
Extension lead – A type of electrical flex that temporarily connects an appliance to a wall socket.
F
Face edge – This is a woodworking term for a surface planed square to the face side.
Face side – Also a woodworking term that refers to the flat planed surface from which other angles and dimensions are measured.
Fence – An adjustable guide to maintain the cutting edge of a tool a set distance from the edge of a work piece.
Freestanding – Furniture or units that aren’t built-in or fixed to a wall or floor.
G
Galvanising – The process of covering an area with a protective coating of zinc.
Gasket – A ring made of rubber to seal the junction between two surfaces; for example, between a toilet cistern and pan on a close coupled toilet.
Grain – The direction of wood fibres in a certain work piece. It’s also a pattern on the surface of timber created by cutting through the fibres.
Gravity-fed Systems – That’s where the mains water is fed into a tank at high level. It usually delivers a low pressure of water; yet, if you need greater pressure you can install a pump for a shower or even increase water pressure to the taps. If you want to calculate the pressure of water from a gravity-fed system, you can check how high the water tank is above the shower or tap. You may wish to ask from a plumber to advise you, just to be sure you have the right calculations.
Groove – A long, narrow channel cut in plaster or wood. In the latter, it follows the direction of the grain.
Grounds – Strips of wood fixed to a wall, providing nail-fixing points for skirting boards, etc.
H
Heating element – It can be used with either radiators or heated towel rails to provide you with a source of heat, independent to the central heating system.
High level cistern – This term refers to the toilet cistern that is mounted on the wall above the toilet and connected to the pan with a long flush pipe. It’s usually found on traditional style toilets with a pull chain flush.
High Pressure – Showers that are marked as high pressure are usually suitable for high pressure systems (like an unvented system or a combination boiler).
Housing – A long and narrow channel cut across the general direction of wood grain in order to form part of a joint.
I
Insulation – Material used to lower the transmission of heat or sound. It’s also a non-conductive material around electrical wires or connections that prevents the passage of electricity.
Isolating valve – This is a valve used to shut off water from a certain room or appliance, so that there’s no need for you to turn off the entire water system.
J
Joist – A horizontal metal or wooden beam used to support a structure like a wall, ceiling, or floor.
K
Key – The process of roughening a surface in order to provide a better grip when it’s being glued.
Knotting – Sealer, made of shellac, that prevents wood resin from bleeding through a surface finish.
Knurled – A series of fine grooves impressed into an edge or surface in order to improve the grip when turned or handled.
L
Laminate – A number of sheets (two or more) of material bonded together, or the top waterproof sheet of the bonded sheets used as a work surface. It is also the process of fixing such sheets together.
Lintel – A horizontal beam that is used to support the wall over a door or window.
Lipping – A decorative strip that is applied to the side edges of laminated boards.
Low level cistern – Usually found on traditional style toilets, the low level cistern refers to the small distance above the toilet, when the toilet cistern is mounted on the wall. It’s connected to the pan with a short flush pipe.
Low Pressure – Showers marked as low pressure are suitable for use on a low pressure system (like a gravity-fed system).
L-shaped shower bath – A shower bath with a wider, L-shaped end for showering.
M
MDF – Medium-density fibreboard. A sheet material made by humans to be used as a substitute for wood.
Mitre – A joint between two pieces of wood formed by cutting 45⁰ bevels at the end of each piece. It also refers to the process of cutting such a joint.
Mixer Shower – Mixer shower mixes the hot and cold-water supply within the shower unit, so that you can control the temperature of your shower. With manual mixers, that are most common, you have to adjust hot and cold water yourself. However, there are also digital showers and thermostatic showers available. They come in units that are either surface-mounted, or can be fitted into the wall.
Mixer tap – A single tap that combines the hot and cold water flows.
Modern - A style of interior decorating with clean and simple elements and draws upon popular design from the 1920s – 1950s.
Monobloc tap – That’s another name for a mixer tap.
Mounting frame – Sitting behind a wall, it’s used to secure a wall hung toilet to the wall.
Multi-Outlet Toilet – A toilet pan that can be connected to any of the three toilet outlet systems. With the right plastic outlet fittings, they can be attached to and S-trap, P-trap or bottom outlet waste outlet system.
N
Noggin – Horizontal reinforcing timber fixed among the vertical studs in a stud partition wall.
O
Outlet – See Shower outlet.
Overflow pipe – A pipe that leads from a tank or cistern used to drain off excess water into an area that will not cause damage in the event of a malfunction.
P
Pan – It’s the part of the toilet also referred to as the bowl.
Pedestal basin – A basin attached to the wall that sits on top of a pedestal and is used to conceal plumbing. It extends all the way from the basin to the floor.
Pillar taps – Single taps that deliver either hot or cold water (not both).
Pilot hole – A small diameter hole that acts as a guide for a screw thread.
Pivot shower door – A shower door that swings open on a supporting upright bar or brackets.
Pop Up Waste – These systems have an operating rod to raise and lower the plug by moving a lever or turning a knob. They’re available for both basins and baths. The rod is concealed behind the taps, so that it gives a tidy finish with clean lines. Some systems operate by pressing the plug to pop up and let the water out.
Power shower – This shower uses an electric pump to boost the flow of water. The power part of this type of shower comes from a pump in the system. The power shower mixes hot and cold water to the desired temperature before pumping the water through the shower head. This typically gives a stronger flow of water compared to an electric shower.
Primer – A coat of paint applied to metal or wood to seal it and act as a first coat.
Profile – The outline or contour of an object.
P-shaped shower bath – A shower bath with a wider, P-shaped end for showering.
PTFE – Tape made from polytetrafluorethylene and used to seal threaded plumbing fittings.
Pushfit connector – A plumbing connection that is pushed onto the pipes e.g. to connect the toilet pan to the waste pipe.
Q
Quadrant – This term usually applies to showers. It’s a triangular shape with a curved front edge. It’s basically a wedge from a circle – like a big slice of pie! Quadrant sizes are given as a radius. Their standard sizing is 800mm or 900mm radius.
R
Rebate – A stepped rectangular recess along the edge of a work piece, typically forming part of a joint. It is also used to cut such a recess.
Reveal – The vertical side of an opening.
Riser or Rising main – A pipe that supplies water under mains pressure, typically to a roof storage tank.
Roll top bath – A type of freestanding bath. It usually comes with a rolled lip around the rim of the bath to help you when getting in and out.
S
Sanitaryware – A term for bathroom fittings that include baths, basins, toilets, and bidets.
Score – To scratch a line with a pointed tool.
Scribe – This term describes: 1) the process of copying the profile of a surface on the edge of sheet material to be butted against it. 2) The process of marking a line with a pointed tool.
Sealed System/Unvented system – While these aren’t very common water systems, they’re becoming increasingly used in flats and houses with limited space as they don’t require a cold water tank or cistern. They’ve got a hot water tank that is under pressure, and typically delivers water at about 3 bar.
Semi pedestal basin – This basin is attached to the wall and sits on top of a short pedestal, also attached to the wall and used to conceal plumbing. The pedestal doesn’t extend all the way to the floor.
Semi recessed basin – This type of basin is designed to fit into, but also overhang, a furniture unit.
Single ended bath – A bath where the taps are situated at one end.
Short Projection – A term for bathroom sanitary ware designed to fit in small spaces. Therefore, a short projection basin will be small from front to back, while a short projection toilet will be narrower from the wall to the end of the rim.
Shower bath – A multi-functional bath that can also be used with a shower. Customised shower baths have a wider end where you can shower and come with a bath screen.
Shower outlet – It connects a shower hose to water pipes.
Shower slider rail kit – A shower in which the height and position can be adjusted on a rail fixed to the wall.
Shower Tray – A waterproof base for a shower enclosure that is fitted onto the floor and contains a waste fitted below. Typical sizes for shower trays are:
- Square shower tray sizes: 760mm x 760mm, 800mm x 800mm and 900mm x 900mm
- Rectangular shower tray sizes: 1000mm or 1200mm long and either 760mm, 800mm, or 900mm wide; 1400mm x 900mm; or 1700mm x 700mm
Shut off valve – It isolates the cold water feed into a toilet in case of any issues.
Silicone mastic – A non-setting compound that is used to seal joints.
Sliding Door – A shower door consisting of two or more panels that slide to one side to allow you in and out.
Slotted waste – Used with basins that have an overflow hole.
Soft-closing Mechanism – A hydraulic closing mechanism that slowly closes doors and drawers or gently lowers toilet seats instead of allowing them to bang shut. The mechanism is hidden inside the hinge or runner.
Soil pipe – It drains waste (water and sewage) from the toilet, basin or bath.
Soil stack – A vertical pipe carrying waste water from a property down into the sewer system.
Space-saver Bath – Baths that taper at the foot end to give more room where the floor space is limited. Sometimes they’re shorter than a traditional bath.
Stack vent – On modern properties, a vent pipe extends to above roof height, to vent gases from the soil stack.
Stopcock – A form of ball valve that controls the flow of a liquid or gas.
Stud partition – A timber frame interior that divides the wall.
T
Template – A cut-out pattern, made from wood, paper, metal etc, that helps in the shaping of a work piece.
Thermostatic mixer valve – Typically found on showers, this valve maintains the temperature by mixing hot and cold water.
Thermostatic radiator valve – A radiator valve that maintains a set temperature by opening and closing automatically.
Thermostatic Shower – A shower with a thermostatic valve that can change water pressure and adjust the hot or cold intake to compensate. Therefore, if someone else is drawing water elsewhere in the house, you don’t get a blast of freezing or scalding water mid-shower.
Towel Radiator – The towel radiators are connected to the central heating system. They’re designed to be attractive and functional. They often have spaces to hang towels through the bars, dry and warm them, as well as to heat the room.
Traditional – A style of interior decorating containing classic, timeless elements, usually from the Victorian and Edwardian periods.
Trap – A bent section of pipe (below a bath, basin, etc) that contains standing water to block smells from escaping back into a property.
TÜV - "Technischer Überwachungsverein" (Technical Inspection Association) are German businesses which provide product inspection and certification. If you see "TÜV approved" on a product, it means that it’s been tested and certified for use. Equivalent bodies in the United Kingdom include the WRAS (see below).
U
U-bend – A U-shaped type of trap.
Undercoat – A layer or layers of paint used to conceal primer and build up a protective layer before the top coat is applied.
Unslotted waste – Used with basins with no overflow hole.
V
Vanity unit – A furniture unit that contains a basin and storage. It can be floor mounted or wall hung.
W
Walk in shower enclosure – A shower enclosure with a smartly arranged set of panels to keep water in, instead of a door.
Wall hung basin – A basin attached to the wall, but with no pedestal.
Wall hung toilet – A toilet attached to a mounting frame behind a wall or unit, so that the cistern is concealed and the pan suspended above the floor.
Waste – It connects a basin, bath or shower tray to a trap, allowing waste water to flow into the waste pipe. It can contain with a plug hole and plug.
Wet room – A waterproofed (“tanked”) room, usually designed with a drain and slight slope to the floor. Wet rooms normally feature an open shower with no need for a shower tray.
WRAS - The Water Regulations Advisory Scheme provides an approval scheme for various bathroom products, to ensure that they use water efficiently and comply with Water Fittings Regulations.
