Toilet Dimensions UK: Projection & Short Projection

Three numbers describe any toilet, and they answer different questions. Projection runs from the wall face to the front edge of the pan — it decides how much floor space the toilet takes. Width is measured across the pan at its widest point, usually the seat shoulders. Height runs from the floor to the top of the pan or, on close coupled formats, to the top of the cistern sitting above it.

The reason size charts mislead is that they compress these three into a single 'overall size' figure, or they list one row per model and leave the reader to guess which dimension changed between variants. On a working site, the confusion costs more than it looks: a pan specified by width alone can still walk itself into a doorway swing or a radiator.

One warning before the numbers. Projection is not rough-in. Rough-in is the plumbing dimension — the wall outlet height on a European P-trap installation, or the floor outlet distance in North America — and it is covered separately in our toilet rough-in guide. Projection is the room dimension: how far the pan reaches into the floor space. A pan can project far while draining through a compact outlet, or the reverse.

We cast 21 toilet pans at the Tangshan works, and their projections cluster into three clean groups. The table below is the map — every figure is the drawing value, in millimetres, straight from the range.

The shortest group is not floorstanding at all: our concealed back-to-wall and wall-hung pans hold 520–525 mm because the cistern moves out of the equation. The middle group — 595 to 630 mm — is what UK buyers are asking about when they search for a short projection toilet. The standard floorstanding group runs 650–665 mm, with one extended body at 740 mm for programmes that specify a larger pan.

Short projection is a trade term, not a certified class — different UK retailers draw the line in slightly different places — but the intent is consistent: a floorstanding pan tightened along its length so it suits cloakrooms, en-suites and small main bathrooms where a standard close coupled body simply eats too much floor.

What actually shrinks is the pan length, and that is a casting decision before it is a catalogue one. The bowl contour, the trapway routing and the rear face that meets the wall all have to be redrawn together — you cannot shorten a standard pan by trimming it. In our range the short floorstanding class runs from 595 mm (CT10228) through 600, 620 and 630 mm, each keeping a full-height floorstanding silhouette.

The honest trade-off: as projection tightens, the bowl gets shallower front to back, so seat depth and bowl interior deserve a check on the drawing before ordering. That is exactly why every model above links to its detail page — the dimensioned drawing is the part of the listing that protects the fit.

The 520 mm class exists because the pan stops carrying the cistern. With the cistern concealed inside the wall on a frame, the only body in the room is the pan itself — and a pan alone reaches far less into the room than a pan plus cistern stacked behind it.

Our wall-hung CH10603 measures 520 x 360 x 365 mm; the concealed back-to-wall CB series lands at 520–525 mm with the seat at a conventional height. The installation demands more upfront — a carrier frame, a concealed cistern and finished wall depth — which is why the format is specified at build or renovation stage rather than swapped in. The system side is covered in our concealed cistern guide, and the format comparison in our back to wall toilet buyer's guide.

For the tightest rooms, the sequence is simple: wall-hung at 520 mm first, then short floorstanding at 595–630 mm, then standard bodies from 650 mm. The step between classes is small in millimetres and decisive in a 900 mm-wide cloakroom.

Across 21 pans, width holds to a narrow band — most bodies sit at 360–380 mm, with one larger pan at 460 mm — because the seat and the human frame set the floor on width long before the designer does. Buyers who need a wider pan are usually solving an accessibility or comfort specification, and that is a deliberate choice of model, not a browsing filter.

Height is where formats diverge. Wall-hung pan bodies list at 365 mm because the figure covers the ceramic alone; concealed back-to-wall pans with a seat land around 420–425 mm; and close coupled formats run 765–875 mm to the top of the cistern. None of these are right or wrong — they answer to different installation heights and cistern positions, which is why the format decision comes first.

The one constant across the range: dimensions do not drift between colour variants. Our C-suffix models — CT10506C against CT10506, CT10603C against CT10603 — share the exact millimetre targets of their base pans, so a colour choice never costs a re-check of the cut sheet.

Start from the plumbing, because it is the part you cannot renegotiate on site. Our back-to-wall and floorstanding P-trap range drains through a wall outlet set 180 mm above the finished floor — 185 mm on three models (CT10502, CT10505, CT10819) — and the wall-hung CH10603 carries its own 55 mm outlet height. The outlet height is measured to the centre of the drain from the finished floor level, and getting it right before tiling is a rough-in question, not a dimensions question.

Then work the room. The projection class sets whether the door can open, whether the radiator keeps its clearance and whether the room reads as a bathroom or a corridor. As a specifying habit: keep the pan's front edge out of the door swing, check the side clearance against the basin, and only then move between classes on the table above.

Everything on this page comes from the range as drawn, and each drawing ships with stated tolerances — fired ceramic holds around two per cent. If a programme needs a dimension the table does not show, the detail pages carry the full cut sheets, or the OEM route can take the question back to the mould.

What is the standard toilet size in the UK? There is no single mandated size. The UK market is dominated by close coupled formats, and the dimension that varies most between models is projection — standard floorstanding bodies commonly run from the mid-600s to 700 mm and beyond, while short projection pans tighten below that class. Our own floorstanding range runs 595–740 mm, all published to the millimetre in the table above.

How do I measure a toilet's projection? Measure from the finished wall face to the front edge of the pan, at the widest reach. If the seat overhangs the ceramic, measure with the seat fitted — the seat is part of what your knees will meet. Keep the tape level; a diagonal reading overstates the pan.

What is the shortest projection toilet you make? The wall-hung CH10603 at 520 mm is the shortest body in the range. On floorstanding pans, the CT10228 at 595 mm is the shortest, followed by the CT10406 at 600 mm — both full-height floorstanding silhouettes with the pan length tightened.

Does a short projection toilet compromise comfort? It tightens the bowl front to back, so very short pans suit smaller frames and occasional-use rooms better than a household's main bathroom. The practical check is the drawing: compare seat depth and bowl interior on the detail page before ordering, rather than trusting the class label.

What wall outlet height do your back-to-wall pans need? The P-trap wall outlet sits 180 mm above the finished floor on most of the range, with 185 mm on the CT10502, CT10505 and CT10819, and 55 mm on the wall-hung CH10603. The height is measured to the centre of the outlet from the finished floor — the same convention as our rough-in guide.

Do colour variants change the dimensions? No. Our C-suffix colour models are cast on the same tooling as their base pans — CT10506C matches CT10506 and CT10603C matches CT10603 to the millimetre. Colour is a glaze decision, not a geometry one.