A successful tiled surface starts with a drawing, not adhesive. Calculating from floor area alone can leave a narrow strip along a wall or a shortage of material from the same production batch. Prepare the layout before ordering and agree on it with the installer.
Even a room that looks rectangular rarely has perfectly straight walls and square corners. Measure its length and width in several places, compare the diagonals, and mark recesses, projections, doorways, drains and areas that will not be tiled. Divide an irregular outline into simple rectangles and add their areas.
Show the actual tile dimensions, joint width and every row on the drawing. The working module is one tile plus its joint: a few millimetres repeated across a long run can noticeably shift the final row.
The floor plan should also reflect the finished interior. Identify the most visible areas—the entrance, open centre, route between kitchen units and edge of a bath. A cut beneath furniture attracts far less attention than one at a threshold or exposed wall.
Starting with a full tile at the far wall often leaves a thin cut on the opposite side. Instead, mark two perpendicular reference axes and check what happens at every edge. A centred, balanced layout usually looks calmer because the perimeter pieces are similar in width and the pattern does not drift without purpose.
A doorway, feature panel, kitchen island or joint continuing from the next room may be a better reference than the geometric centre. For a tiled field flowing through several spaces, establish priority lines for the whole area.
Test several starting positions. If centring produces a cut substantially narrower than half a tile, moving the grid by half a module will often create stronger-looking edges. This is a practical preference, not an absolute rule: a recess, access panel or decorative focal point may justify another solution.
Common patterns affect both the appearance and the number of cuts:
Choose in response to the room itself. A diagonal pattern changes perception but does not correct crooked walls. In a modular layout, a small dimensional mismatch within one repeat accumulates across the surface.
Direction matters with rectangular tiles. Lengthwise joints emphasise depth, while crosswise lines can make a narrow area appear wider. Wood-effect tile often follows the main line of movement; with a stone design, decide in advance whether veins should connect between pieces.
Light changes the result too. Relief and long joints are more pronounced in low-angle daylight, so view sample pieces by day and under the main artificial lighting. If the backs carry arrows, consult the manufacturer: using one orientation or rotating pieces may produce different effects.
Set out at least two intersecting rows without adhesive, using spacers of the specified thickness. Assemble several complete repeats of a modular design. This reveals the true width of perimeter cuts, vein continuity, joints at doors and difficult cutting points.
Check pipes, concealed cistern frames, access panels and floor sockets separately. A hole close to an edge may weaken a narrow piece, so a small grid adjustment can be safer. Mark where an offcut from a straight cut can be reused, but only when its dimensions, design and orientation suit the new position.
Open several boxes when the surface has shade or graphic variation. Balance the pieces and reserve less suitable motifs for discreet cuts. Verify the drawing against the material, not just an image on screen.
Give the installer a dimensioned plan showing reference axes, joint width and starting area. A catalogue picture can explain the idea, but it cannot define every critical edge in a complex project.
Calculate the net area, then check the drawing tile by tile and round the order up to complete boxes. Count decors and separate formats independently.
Around 10% extra is a common starting point for a simple straight grid in an uncomplicated room. A diagonal layout, irregular outline, modular composition or fragile large format may call for 10–15%, and sometimes more after a piece-by-piece review. These figures are planning guides, not universal rules.
When setting the allowance, consider:
Repair stock matters for a distinctive shade or texture. Later batches may differ, or the range may disappear. Keep full pieces with the box identification.
For example, 20 m² plus a 10% allowance equals 22 m², but the final order must still be rounded to whole boxes. If the plan contains many one-off cuts, adjust the quantity before ordering.
A reliable porcelain tile layout combines accurate measurements, visual axes, the real tile-and-joint module, design direction and a check of every edge. Compare alternatives, dry-lay the material and only then confirm the order. Explore formats and designs in the ITUM porcelain tile catalogue; for a complex plan, consult both the supplier and installer.