Tiles

Batch, calibre, and shade of tiles: why buy everything at once and with a reserve

Wall and floor tiles are produced in batches, and each batch may have slightly different shades and sizes. Therefore, each box has a shade and calibre code. RAKO warns that tiles with different shades or sizes must not be used on one surface. We explain what the data on the box means, what shade variability V1 to V4 is, and how to proceed when additional tiles need to be purchased.

Prepared by: TGB Kúpeľne team, bathroom showroom in Senec since 1991updated 9. 11. 20265 min read

Illustrative image: bathroom with large-format tiles in a stone imitation with natural variations in the pattern

Ceramics are a natural material fired in a kiln. Even with precisely set production, the colour and size can vary slightly from firing to firing. Therefore, manufacturers sort tiles into batches and label each batch. Those who understand this can buy wall tiles without surprises – and know how to manage when a few tiles are missing. You can choose collections for your bathroom in the photo gallery Wall and floor tiles.

What is a batch

A batch is a production batch of tiles that have the same shade and the same actual size. RAKO states that it labels the batch on pallets, on cartons, for rectified products also on the edge of the tile and on delivery notes. The shade has a code on the carton with two to three characters, and the size is given in millimetres.

RAKO's basic rule is: tiles from batches with different shade designations or declared sizes must not be used on one surface. Before laying, check the data about the delivered batch on the packaging.

Shade: same code, same colour

The difference between batches is usually small – you won't see it on one tile in the shop. However, on a finished wall, two batches side by side will create a visible stripe or spot. Therefore, the rule is: only one shade code per surface. When receiving goods, compare the code on all boxes.

Calibre: actual size of the tile

A tile sold as 60 × 60 cm actually measures, for example, 598 × 598 mm. The nominal size in centimetres is a commercial designation according to standard EN 14411, the actual (manufacturing) size is on the packaging in millimetres. If tiles with a difference of even one millimetre are mixed on one surface, the grout joints will not align, and the difference will accumulate across the entire wall. For rectified tiles, the differences are minimal, so the grout joint can be narrow – more in the articles Rectified tiles and Tile and floor formats.

Shade variability V1 to V4

In addition to differences between batches, tiles also vary within a single batch – intentionally, to make the imitation of stone or wood look natural. The degree of differences is expressed by a scale used by the American standard ANSI A137.1 and many manufacturers in their catalogues:

The degree is indicated by the manufacturer in the catalogue or technical sheet. A solid-colour wall tile usually has V1, while stone, marble, and wood imitations have higher degrees to appear natural.

For example, RAKO indicates degree V4 for Core floor tiles 60 × 120 cm. For V3 and V4, manufacturers recommend taking tiles from multiple cartons at once during laying to mix the shades evenly across the surface – RAKO mentions this for the Cava series, for example. Therefore, variability within a batch is not a fault, but a difference between batches is if mixed on one surface. Collections with stone and wood patterns can be found in the sections Stone, Travertine, and Wood imitation, for example, Marazzi Stream Travertino – check the degree of variability of a specific series in the manufacturer's catalogue.

How much to buy and why at once

• The entire quantity at once – from one batch, with all accessories (skirting, decor, stair tiles). If ordered later, the same batch may no longer be available.
• Reserve – about 10% for cuts, more for intricate bathrooms and patterns. RAKO recommends increasing the quantity by up to 25% for large formats from 45 × 45 cm. You can find the calculation in the article How much wall and floor tiles to buy.
• Box for repairs – RAKO advises keeping leftover wall and floor tiles for potential future purchases. One box in the basement can save a cracked tile for ten years – see Cracked tile.
• Receipt and label – keep the purchase receipt and the label from the box with the batch code.

What to check when receiving

1. The same shade code and size on all boxes.
2. Boxes undamaged during transport.
3. Before laying, open several boxes and lay the tiles side by side dry – with V3 and V4 you will see how the shades alternate.
4. Address any visible defects before laying. RAKO warns that even in 1st class, the standard allows up to 5% of tiles with visible defects.

What to do when you need to buy more

1. Find the label from the original box – shade code and size.
2. Ask the seller where you bought the tiles if the same batch is still available.
3. If not, place the new batch on a separate surface – on a different wall, in another room, or behind an edge interrupted by a corner, door frame, or trim. Never in the middle of one surface.
4. Compare live – the old and new tile side by side in daylight, not in a photo.

Sources: RAKO – shades and sizes (batches, codes, dimensions); RAKO – customer information sheet (SK); RAKO – product information sheet 2019 (reserve for large formats, leftovers); RAKO – Core (V4) and Cava (tiles from multiple cartons) catalogues; Ceramic Tile Foundation – shade variability V0 – V4; ANSI A137.1; EN 14411; EN ISO 10545-2; our articles How much wall and floor tiles to buy and Rectified tiles.

Terms in the glossary: Caliber and shade (batch) · Rectified tiles · Nominal and actual size · Travertine · Large-format tiles