Tile ordering is not simply a matter of multiplying room length by width. Corners, cut-outs, laying patterns, tile size, breakage and future repairs all affect the final requirement. Tiles from different production runs may also vary slightly in shade or dimensions, even when the product name and design are the same.
A clear quantity plan helps homeowners, architects, hotel teams, retailers and project buyers avoid shortages, excessive leftovers and visible batch differences. Measurements should be checked on site, while carton details and layout decisions should be confirmed before installation begins.
Start with accurate site measurements
Measure each surface separately in metres. For a simple rectangular floor, multiply length by width to calculate the area in square metres. Divide L-shaped rooms, passages, columns and other irregular spaces into smaller rectangles, calculate each area and add the results.
For walls, multiply the width of each wall by the intended tiled height. Measure wall sections separately where the tile height changes. Keep floor, wall, skirting, staircase and feature-area quantities separate because they may use different tile formats or designs.
How to handle doors, windows and fixed elements
Large openings such as doors and windows can be deducted from the gross wall area. Small openings, pipe penetrations and electrical boxes are often better left within the measured area because cutting around them can consume additional tiles.
Do not automatically deduct the footprint of every kitchen cabinet, vanity or fixed fitting. First decide whether tiling will continue behind or below it. Tiling concealed areas can make future layout changes easier, but this decision must be included in the specification and budget.
Measure skirting separately
Skirting is usually calculated by running length, not floor area. Measure the perimeter requiring skirting, deduct untreated door openings and add an allowance for cuts and corners. Confirm whether skirting pieces will be factory-made, purchased separately or cut from full tiles. Site-cut skirting consumes floor tiles and must be added to the order.
Convert measured area into order quantity
After calculating the net area, add the selected wastage allowance. Then check the coverage stated on the carton and round the order up to complete cartons. Suppliers generally sell tiles by the box, so the theoretical area and the purchasable quantity may not be identical.
For example, if the net tiled area is 40 square metres and the agreed allowance is 10%, the planned quantity is 44 square metres. If one carton covers 1.44 square metres, 30 cartons cover only 43.2 square metres, so the order must be rounded up to 31 cartons. Always use the coverage printed on the relevant product carton or confirmed documentation rather than assuming coverage from the stated tile format.
Check nominal and actual dimensions
A tile described by a common market size may have a slightly different actual dimension. Joint width also affects how a repeated module fits across a room. For large projects, calculate both the total area and the number of tile modules across critical dimensions. This is especially important for narrow passages, wall bands, lift lobbies, bathroom niches and other areas where repeated cuts can substantially change consumption.
Choose a suitable wastage allowance
There is no single allowance that suits every project. Wastage depends on the layout, room geometry, tile size, product variation, installer planning and the number of edges or openings. The allowance should be agreed after reviewing the drawings and site conditions.
- Simple straight layouts in regular rectangular spaces generally need a lower allowance.
- Diagonal layouts, herringbone patterns and designs with many directional cuts generally need more.
- Irregular rooms, angled walls, columns, niches, floor traps and sanitary fittings increase cutting.
- Large-format tiles may require more careful planning because one damaged or unsuitable piece represents a larger area.
- Book-matched, face-sequenced or direction-sensitive designs require a piece-by-piece layout plan.
- Tiles used across several small rooms may create more offcuts than the same area installed in one open room.
As a planning starting point, buyers commonly discuss an allowance of around 5% for straightforward layouts and around 10% or more for complex patterns or heavily cut areas. These are not fixed rules. The final figure should follow a cutting plan prepared by the architect, designer, retailer or installer.
Understand what wastage includes
Wastage is not limited to tiles broken during work. It also covers edge cuts that cannot be reused, pieces rejected for visual placement, drilling damage and tiles reserved for future repairs. Better layout planning can reduce avoidable waste, but an unrealistically tight order can stop work if a matching batch is unavailable later.
Plan the layout before finalising the order
A tile layout should show the starting point, joint direction, feature alignment and cut positions. Check whether the room should be centred, aligned with a doorway, continued into an adjoining area or coordinated with sanitary fittings and cabinetry.
A dry layout or digital setting-out plan can reveal narrow edge strips and awkward transitions. Small adjustments to the starting line may produce better-looking cuts and improve tile use. However, the layout should not be changed on site without considering how it affects connected rooms and total quantities.
Manage shade, calibre and batch matching
Fired ceramic and vitrified products can show differences between production runs. Carton labels may identify shade, calibre, size code, batch, lot or production details, depending on the manufacturer. The exact terminology varies, so buyers should ask the supplier to explain the label.
Order the full requirement for each continuous visible area together wherever possible. On delivery, compare carton labels and separate any boxes with different identifiers. Do not assume that cartons with the same product name or catalogue code will automatically match.
- Check the product code, finish, stated size and carton coverage.
- Compare shade, calibre, batch or lot references shown on the cartons.
- Open sample cartons in good natural or site-equivalent lighting.
- Lay several loose tiles together to review colour, pattern and dimensional consistency.
- For intentionally varied designs, mix tiles from several cartons during installation to distribute faces naturally.
- Keep mismatched or questionable cartons aside until the supplier or project team has reviewed them.
Tiles of different calibre may not align neatly within one grid or joint width. Different shades can become particularly visible across an open floor or uninterrupted wall. If separate batches must be used, allocate them to distinct rooms or areas divided by doors, corners or movement joints rather than mixing them randomly on one surface.
Inspect, record and store the delivery
Count cartons at delivery and note damaged packaging before acceptance. Photograph carton labels and retain the invoice, product code and batch information. Store boxes in a dry, secure area according to the supplier’s handling guidance, and avoid removing labels before the stock has been allocated.
Installation should not begin until the quantity, layout and visual mix have been approved. Once tiles are fixed, resolving a shade or pattern concern becomes much more difficult. The installer should also confirm that enough approved material remains to complete the full connected area.
Keep repair stock
Retain a small quantity of unused tiles from the installed batch for future repairs. The appropriate amount depends on project size, tile availability and the likelihood of access work. Hotels and managed properties may need a documented reserve for rooms, corridors and service areas. Mark spare cartons with the location, product details and batch, then store them where they will not be damaged or mistakenly used elsewhere.
Practical order checklist
- Measure every floor, wall, skirting and special feature separately.
- Confirm the exact tiled limits and whether concealed surfaces are included.
- Approve the tile format, laying pattern, joint width and starting lines.
- Add a project-specific allowance for cuts, breakage and repairs.
- Convert the requirement using the stated carton coverage and round up to full cartons.
- Order connected visible areas from one matching batch where possible.
- Inspect labels and sample tiles before installation.
- Record batch details and reserve suitable spare tiles.
Conclusion
Reliable tile planning combines accurate measurement, layout review, sensible wastage and careful batch control. Calculate each surface separately, order in full cartons, inspect shade and calibre before fixing, and retain matching repair stock. A little planning before purchase is far less disruptive than trying to source matching tiles after installation has started.