Wall tile specification: complete selection guide 8 standards

By Osman Orman · Tile and technical specialist at Tegelmonsters

A specification for wall tiles consists of ten fields: classification according to EN 14411, format with caliber, dimensional tolerance according to ISO 10545-2, water absorption, surface finish, color register, tile adhesive according to EN 12004, grout according to EN 13888, expansion joints, and fixing substrate.

With this set, the specification is unambiguous for the contractor. For the architect, the benefit lies in a specification block that recurs across projects in a similar structure.

Cutlery block

What belongs in a wall tile specification?

The Dutch specification standard STABU does not prescribe which wall tile to use, but rather how to name it. The standard basis is derived from two international layers: EN 14411 with ISO 10545-x for the tile product and NEN-EN 12004-1 with NEN-EN 13888-1:2022 for the installation products. For the architect working with multiple disciplines, this structure provides a common readability.

The fields are interdependent. A wall tile in BIII classification requires a different adhesive than a rectified porcelain tile in BIa, and the joint width follows from the edge finish. A good specification block explicitly states the relationships, so that a change in one field automatically triggers the others during the tendering process.

For projects where large-format wall tiles are listed in the specifications, you can supplement the specifications with the rules from our guide for large format in projects . It explains how format affects the choice of adhesive, joint width, and transport.

Decision table

Which room requires which wall tile specification?

The space dictates the specification. A wet zone requiring daily cleaning demands low water absorption, a chemical zone requiring intensive cleaning requires reactive resin grout, and a commercial zone dictates wear resistance and adhesive strength. To match wear class and anti-slip value per room, the supplementary functional table for PEI and R-values ​​per room can be found in our selection guide .

Classification

Which EN 14411 classification applies to ceramic wall tiles?

EN 14411 is the European standard that classifies ceramic tile production. The capital letter B refers to the “pressed” production method, after which the Roman numerals indicate the water absorption class. The water absorption itself is measured according to ISO 10545-3 , using a procedure in which tiles are immersed in water under vacuum. The result is a percentage of the dry tile weight.

For wall tiles, BIII is a common class. The higher absorption makes the tile denser, lighter, and cheaper, but suitable for walls because it is not subjected to mechanical stress. However, for wet wall areas, such as a shower room or swimming pool surround, you should choose BIb or even BIa porcelain. The lower absorption results in less moisture absorption into the body, a lower risk of discoloration, and better chemical resistance.

The classification is always at the top of the specification block because it guides the other choices. A rectified BIa porcelain tile requires a C2TE-S1 adhesive, while a BIII with a natural edge finish works best with C2T and a wider joint width. For projects with large-format wall tiles, BIa works by default because the higher density absorbs the cyclic movement.

Format

How do you specify size and caliber according to ISO 10545-2?

The size is noted as width times height, with the designation rectified or not. ISO 10545-2 specifies measurement methods for length, width, thickness, straightness of the sides, squareness of the corners, and flatness of the tile. For rectified wall tiles, the standard is stricter than for tiles with a natural edge finish, because they are installed with narrow joints.

The caliber is the designation of the exact production dimension within the tolerance. For example, a manufacturer supplies a tile with a nominal size of 30×60 cm in calibers W1 (29,8 x 59,8), W2 (29,9 x 59,9), and W3 (30,0 x 60,0). During installation, the tiler keeps a batch in a specific caliber; otherwise, joint deviations will occur that are visible on the wall. Therefore, you always specify the caliber in the specifications or have the supply arrive by caliber.

For wall tiles larger than 60×120 cm, size is a more significant factor, as a deviation of 0,5 percent already amounts to a millimeter along the longest side. The architect specifying wall tiles in this format links the caliber to the execution and plans a test setup with multiple samples before placing the order. For details on rectification and joint width, see our selection guide for joint width in rectified tiling.

Finish

How do you specify surface finish, color register, and rectification?

The choice of finish is a design variable that must be stated unambiguously in the specifications. A matte tile reflects less light, appears calmer, and hides water splashes better. A glossy tile creates a spatial effect through reflection and is popular in lobbies and boutique hotels. A textured finish provides tactility, especially on accent walls or in spa projects where wall contact is part of the experience.

It is preferable to define the color register using an NCS code or LRV band, rather than a free color description. A specification such as “warm white” leaves room for interpretation, whereas an NCS S 0502-Y designation or LRV band 75-85 does not. For developing the color register for projects, our tile color selection guide includes a frame with four design variables.

Rectification is noted as a property of the tile, not as a separate rule. A rectified tile has clean-ground edges, allowing the grout to be up to 2 mm. For wall tiles in public spaces and the hospitality industry, rectification is often the default, because the clean grout creates a calmer surface. For residential projects with a classic look, a tile with a natural burn-edge might actually be a better fit, with a wider grout of 3 to 4 mm.

Glue

Which tile adhesive according to EN 12004 is suitable for wall tiles?

NEN-EN 12004-1:2017 classifies tile adhesives based on composition and properties. The letter C stands for cement-based, the number 2 for improved bond strength above the basic class, T for anti-sagging in wall applications, E for extended open time, F for fast curing, S1 for deformable, and S2 for highly deformable. For wall tiles, the letter T is essential because the tile hangs vertically and must not sag before the adhesive has set.

For standard sizes, C2T applies as the minimum. From 60×60 cm on the wall, the specification switches to C2TE-S1, as the heavier weight and larger surface area require more adhesion and flexibility. For wall tiles larger than 80×80 cm or slabs on a wall, choose C2TE-S2, with buttering on the tile back to eliminate any hollow spots. The notching of the trowel follows the size: 6 mm for small, 8 mm for 30×60, 10 mm for 60×60, 12 mm for large format.

A separate procedure applies to wall-to-floor transitions with underfloor heating. In these cases, the wall tile adhesive must accommodate the cyclical movement creeping upwards from the underfloor heating. A C2TE-S1 with flex additive is standard for this situation. For the complete selection of adhesives and grout in conjunction with underfloor heating, the broader framework can be found in our guide for tiles and underfloor heating in projects.

Add

Which joint mortar according to EN 13888 is specified in the tender?

NEN-EN 13888-1:2022 classifies joint mortars based on composition and behavior. CG stands for cement-based, the number 2 for improved properties, W for low water absorption, and A for wear resistance. RG stands for reaction resin-based, with designations expressing chemical resistance and color fastness. For wall projects in dry zones, CG2 WA is the standard; for wet zones with intensive cleaning, you scale up to RG.

The grout color is a design choice that you specify in the same line. A tone-on-tone grout allows the wall surface to flow seamlessly, while a contrasting grout accentuates the tile pattern. For wellness and public bathrooms, grout in a shade darker than the tile usually works better, as cleaning and graying are less visible. A full explanation of grout color and broader combinations can be found in our guide to grout color per tiled wall or floor.

For corner sealing between wall and wall or wall and ceiling, choose a silicone joint instead of a cement joint. For wall and floor finishes, the Building Decree refers to the performance requirements, which can be found on Bouwbesluit Online . The silicone accommodates movement between two structural elements, each undergoing its own shrinkage and thermal cycle.

Sample package

How do you put together a specification block sample package for wall projects?

On the wall tiles page , you can filter for free by size, color, classification, and finish. For a specification project, set the filter to rectified, EN 14411 class BIb or BIa, and the intended size. This immediately displays the collections used in project architecture, and allows you to bundle sample requests at the project level via the Sample Folder.

What project managers often tell us: the first filtering round takes place online, followed by the physical assessment in our showroom in Utrecht. The showroom is accessible to professionals by appointment only and offers full-size samples alongside additional sample surfaces. Our manufacturers from Spain and Portugal supply technical datasheets that endorse the EN 14411 classification and caliber designation, enabling the architect to complete the specification block directly from the delivery documents.

Frequently asked questions