Concealed Toilet Buttons

What a concealed flush plate is

With an in-wall cistern, the flush plate is the only part you see, and it can also be how a plumber reaches the cistern. The Caroma Invisi Series II listings say the plate gives complete service access, so servicing does not mean removing tiles. The cistern is built into the wall, so a plate is made for one cistern or one cistern series. Find the make and series of the cistern behind your wall before you think about finish. The make and model are usually stamped on the cistern, and a plumber can read them once the old plate comes off. You can usually replace just the plate, as long as the new one matches that cistern. Buttons for toilets with an exposed cistern are on cistern toilet buttons.

Plates for Caroma Invisi Series II cisterns

The Caroma plates come in round, rectangular and oval shapes. Finishes include brushed nickel, brushed brass, brushed bronze, matte black and gunmetal, and the round plate also comes in white and grey tones. The fixings are fully concealed, and the plate mounts on the wall above the toilet or on a benchtop. The pneumatic buttons need only a light touch. The rectangular listing adds that with the remote option the buttons can sit up to 4m from the cistern.

The round metal plate is 210mm wide, 110mm high and 5.5mm deep. The Contura II round button panel is 228mm by 116mm, in brushed brass, brushed nickel, brushed bronze, chrome and black. The raised care buttons are listed as easy to push and installable to comply with AS1428.1, and accessible toilets covers the wider fit-out. The whole range is on Caroma concealed toilet buttons.

Plates for Geberit Sigma cisterns

Most of the Geberit Sigma 20, Sigma 20 square, Sigma 30 and Sigma 60 plates list a Sigma 8 cistern. Two Sigma 20 listings name no cistern, so confirm the fit before you order. The Kappa 50 plate pairs with the Kappa Under Counter 150 concealed cistern and doubles as its access panel.

Other makers list plates for Sigma cisterns too. The Turner Hastings Claremont plate is brass, made in Italy, and suits Sigma 8 in-wall cisterns, in brushed brass, chrome and brushed nickel. A Geberit cistern has offset valves, so the listing says the plate sits 8mm to the right of the toilet centreline. The Fienza Sigma round button plate is ABS with a PVD finish, 246mm wide and 164mm high, in chrome, matte chrome, matte black, matte white, brushed nickel, brushed copper, gun metal and urban brass. The Meir Sigma 21 plate is brass with a PVD finish, the same 246mm by 164mm, in brushed nickel, champagne, lustre bronze, tiger bronze and shadow. The pages to use are Geberit concealed toilet buttons, buttons to suit the Geberit Sigma 8 cistern and Geberit cistern and toilet suite packages.

Seima and Nero in-wall plates

The Seima 500 Series plate suits all Seima in-wall cisterns. It is a rectangular ABS plate, 236mm wide and 152mm high, with full and half flush buttons, in matte white, matte black, brushed nickel, gunmetal, brushed gold and chrome. The listings add that button options are sold separately and that the pneumatic action needs only a light touch.

The Nero in wall push plate suits the R&T in wall cistern, and the Bao Elegant in wall suite that uses it. It is 304 grade stainless steel with soft rounded corners and fully concealed fixing, and the finishes include brushed gold, brushed nickel, brushed bronze, graphite and gun metal. The graphite listing gives the plate as 258.6mm wide, 178.6mm high and 28.6mm deep. The brand pages are Seima concealed toilet buttons and Nero concealed toilet buttons.

Meir, Fienza and Turner Hastings, from their listings

The Meir Sigma 21 plates are described as made in Switzerland and assembled in Australia. The Shadow finish listing says its brownish-bronze undertones come to life under warm white lighting and look different under cool white lighting. That is a good reason to see the plate in your own light before you commit. The Fienza Sigma round button plates are ABS plastic for use with Sigma cisterns. The Turner Hastings Claremont listing names the cistern codes 109.795.00.1 and 111.698.00.1.

Both codes appear in the Geberit Australia brochure. One is the 4 star Sigma8 cistern for a back to wall pan, and the other is the 4 star Sigma8 with a frame for a wall hung pan. So the Claremont listing is written against the same cisterns as the brochure. When a listing gives a cistern code, compare it with the sticker on your cistern and not only with the name.

How a plate and a cistern pair up

Geberit's Australian pages say flush plates share the name of the concealed cistern they fit. Sigma plates fit Sigma cisterns, Omega plates fit Omega cisterns, and the Alpha is for under-counter use. A new plate can go with an older Geberit cistern, but a plumber should confirm the installed cistern and the compatible plate. The Geberit Pro app can identify a cistern from a photo of the plate.

The same logic holds for every make here. The Caroma Invisi Series II plates are for the Invisi Series II cistern, the Seima 500 Series plate is for Seima in-wall cisterns, and the Nero push plate is for the R&T in wall cistern. A plate that looks right but belongs to another cistern will not seat or connect, so confirm the cistern first and pick the finish second.

What the maker documents say, side by side

The plates here come from four makers, and their own documents give different figures for the same things. The Caroma Invisi II datasheet describes pneumatic buttons that can be activated up to 4 metres from the cistern, a standard plate that suits a wall lining of 6mm to 45mm, and a round plate 210mm wide and 110mm high. The Geberit Australia brochure describes Sigma plates of 246mm by 164mm, remote buttons that can sit up to 2 metres from the cistern, and a minimum wall lining of 30mm for the Sigma60 to sit flush. The Seima 500 Series listing gives a plate 236mm wide, 152mm high and 8mm deep. A plate that looks small on a screen can be a large rectangle on a wall, so compare the millimetres, not the pictures.

Water figures belong to the cistern, not the plate, but the documents are worth reading together. The Caroma datasheet gives an average flush of 3.5 litres from a 4.5 litre full flush and a 3 litre half flush, and 4.0 litres at 6 and 3 litres. The Geberit brochure gives 3.4 litres for the Sigma8 and 3.3 litres for the Kappa under counter cistern at 4.5 and 3 litres. The gap comes from different cisterns, so there is no reason to choose a plate because of these numbers.

Service access decides more than finish

The documents agree on one point: the plate is how the cistern is reached. The Caroma datasheet separates plates and buttons that suit cistern access from custom buttons that need alternative access, and for the second case it lists a blank access plate and large access panels. The Geberit brochure says a remote button cannot be used to service the cistern, so separate access is required.

The NSW Government plumbing advisory note 18/2022 goes further. It says that cutting gyprock, or breaking fire rated, tiled and waterproof elements, in the future is not appropriate access to something that must be accessible. It reports audits of Class 2 buildings that found such items inside walls that were waterproofed, tiled and fire rated with no provision for access, and says the cost of fixing that falls on the owner or occupier. Whatever plate you pick, decide where the service opening is before the wall is closed.

Which plate type suits which wall

A plate that is also the access panel suits a wall where the cistern sits directly behind the toilet. A remote plate suits a wall where the cistern is somewhere else, such as a ceiling void, a duct or a vanity, and it needs its own access. A Sydney Bathroomware guide to flush plates sets out the same split. Mechanical plates are reliable and easy to service but need the cistern behind them. Pneumatic plates move air through hoses so the cistern can be remote. Electronic plates work by a hand wave but narrow the choice of cisterns. If you want a remote plate, ask the plumber early.

Accessible bathrooms

If the toilet is for someone with limited reach or grip, the control and its position matter as much as the finish. The Design for Dignity accessible toilets guide, published with the Australian Network on Disability, gives the flush control zone as 600 to 1100mm above the floor. The back-mounted zone is 500mm wide from the toilet centre toward the side away from the wall, and the side-mounted zone is 300mm either side of the toilet front.

Caroma's raised care buttons are listed as easily installed to meet AS1428.1-2009 Amendment 1, and Geberit's remote range includes a white care button. Both speak to the button, not the room, so ask a certifier or access consultant to confirm the whole fit-out. The wider room is covered on accessible toilets.

What the installation leaflets and data sheets add

The Caroma installation leaflet for the Invisi Series II plates is number 237510, revision B, and it covers round, rectangular, care and blanking panels. The pneumatic tubes push into the rear of the mounting panel, each tube matched to its button, and the panel is fixed to the tiling box or remote mounting box with the supplied Allen key and screws. The leaflet says to trim the box flush to the wall before assembling the buttons, and in capitals not to over tighten the mounting panel screws. Custom buttons need a hole of 65mm by 57mm, or a round hole of 57mm, and suit panels up to 55mm thick.

The Seima sheet for the Flush Plate 500, version 10.0 dated February 2026, lists seven finishes and a separate order code for each pairing of finish and actuation. The pneumatic plate and the mechanical plate are different parts, so the plate and the cistern must use the same actuation. The Geberit data sheet for the Sigma60 glass plate is the most restrictive. It suits Sigma concealed cisterns of 8 centimetres from the 2016 range and covering thicknesses of 24mm to 50mm, and it is not suitable for Geberit Duofix elements for wall hung toilets in barrier free applications. The sheet also carries a note that the plate is phasing out, so ask the supplier about replacements before you rely on it.

Looking after the plate

Finish decides care. The Buildmat help centre advises cleaning brushed brass with a soft damp cloth and mild dish soap, wiping with the grain, then rinsing and drying. It says to avoid acidic cleaners, bleach, abrasives and vinegar, and that water left on brushed brass causes mineral deposits that get harder to remove the longer they sit. That advice suits the brass PVD plates here. For ABS and stainless steel plates the safe default is much the same: a soft cloth, mild soap, no abrasives, and no spray cleaner left to sit. If a button feels stiff or the flush changes after cleaning, the cause is behind the plate and a plumber should look.

What an Australian buying guide says about plates

The MyHomeware guide to push button toilet flush types sets the in-wall cistern next to the other styles. It says the cistern and internal parts sit inside a wall frame, so only the button shows on the tiled surface, and that the cistern has a built-in access panel for servicing without removing wall tiles. It gives in-wall plate sizes as 180mm or 240mm and advises confirming compatibility with the frame. The sizes in this page's listings fall in the same range, from the 210mm Caroma round plate to the 246mm Geberit Sigma plates. The guide also says button plates and actuator covers can often be swapped without disturbing the cistern internals, which matches the Geberit and Caroma advice that the plate can be replaced when it matches the cistern.

It makes a point that is easy to miss: upgrading only the button does not change the flush volume. A dual flush cistern gives a 4.5 litre full flush and a 3 litre reduced flush, averaging about 3.3 litres under the WELS calculation, and Australian toilets must not exceed a maximum average flush volume of 5.5 litres. Those figures sit close to the cistern data in the Geberit and Caroma documents. Buy the plate for its fit and finish, not for any water saving.

Sensor plates and what they ask of the room

The MyHomeware guide also covers touchless plates. It says they trigger the flush when your hand comes from 10cm to 30cm away, using infrared or capacitive sensing, and run on batteries or hardwired mains power. A mains connection needs a licensed electrician, and steam from hot showers can cause false flushes, so the sensor should face away from the shower zone. The plates here are mechanical or pneumatic buttons, so these points matter only if you are weighing a sensor plate against them. The Geberit instructions list the Sigma80 as a Bluetooth sensor flush button, which would be a separate decision with the plumber and the electrician.

Why guide ranges differ from maker figures

A second MyHomeware guide, to in-wall cistern toilets, gives typical ranges. A cistern is 500 to 600mm high, 350 to 400mm wide and 90 to 150mm deep, the wall cavity is at least 150 to 200mm, and flush plates are 150 to 200mm high and 200 to 250mm wide. It says these figures vary by manufacturer and model. The maker documents give exact figures for exact cisterns. The Geberit Sigma8 brochure labels its in-wall cistern 80mm and the Duofix 90mm, and the Caroma Invisi II datasheet gives a minimum cavity of 90mm for an in-wall installation. Use the ranges to get a feel for the space and the maker figures to set out the wall.

The guide also advises planning access for maintenance through the flush plate or an access panel, so repairs do not need extensive wall damage. The NSW advisory note makes the same point in its own terms.

Who fits the plate

The MyHomeware guide says cistern internals and connections to the water and waste pipes need a licensed plumber, who must provide a compliance certificate. It adds that any flush component sold in Australia must carry WaterMark certification. A plate swap that only lifts off a cover is different from work on the cistern, and the makers' own instructions describe the swap as simple. If the plate does not lift off easily, if the flush changes after a swap, or if there is any sign of a leak, call a licensed plumber rather than pulling parts out.

Before you order

Read the compatibility line on the listing against your cistern. If you are planning an in-wall toilet from scratch, start with in wall concealed toilets. Seat hinges, caps and seats are on toilet components, and the main toilets guide covers choosing a whole suite.