Technical area

Quick reference table

Why white body wall tiles are not suitable for floors or outdoor use

Its water absorption exceeds 10%. Water penetrates the body and, if it freezes, expands and causes the tile to spall. In addition, its breaking load is an order of magnitude lower than that of porcelain tile. It is an excellent product for interior wall cladding and should not be used beyond this application.

Characteristics applicable to all ceramic tiles

Regardless of their intended use, according to UNE-EN 14411:

Parameter by parameter

Water absorption — UNE-EN ISO 10545-3. Determines the classification group. It is the parameter that conditions all the others.

Breaking load and flexural strength — UNE-EN ISO 10545-4. The force the tile can withstand before breaking. Reference values: ≥ 450 N for walls; ≥ 900 N for floors with light to heavy traffic; ≥ 2,000 N where loads are moved; ≥ 4,500 N for urban paving with light vehicles.

Surface abrasion resistance (PEI) — UNE-EN ISO 10545-7. This wear parameter applies to glazed tiles and measures how many cycles the glaze withstands before its appearance changes.

Scratch hardness (MOHS) — EN 101. A scale from 1 to 10 indicating the glaze’s resistance to scratching. It complements PEI: PEI measures wear caused by abrasion, while MOHS measures localised scratching.

Slip resistance — explained in the Slip Resistance tab.

Frost resistance — UNE-EN ISO 10545-12. Requires water absorption below 3% and successful completion of the freeze-thaw cycle test. Porcelain tile meets this requirement; white body wall tile does not.

Thermal shock resistance — UNE-EN ISO 10545-9. Behaviour when exposed to sudden temperature changes.

Chemical resistance — UNE-EN ISO 10545-13. Classes A/B/C for household products and swimming pool salts; classes LA/LB (low concentration) and HA/HB (high concentration) for acids and alkalis.

Stain resistance — UNE-EN ISO 10545-14. From Class 5 (the stain can be removed with hot water) to Class 1 (irreversible). The minimum standard requirement is Class 3.

Moisture expansion — UNE-EN ISO 10545-10. Expansion of the tile due to moisture absorption. Maximum 0.6 mm/m. A high value can cause floor tiles to buckle.

Crazing resistance — UNE-EN ISO 10545-11. Formation of microcracks in the glaze caused by stresses between the glaze and the body. This test is particularly relevant for glazed products.

Commercial data that are not test results

Shade (batch) — Tiles are grouped according to their firing shade. Tiles of the same model but with different shades should not be mixed within the same installation area.

Calibre — Actual dimensional group within the manufacturing tolerance. As with shade, the same calibre should be used throughout each installation area.

Rectified — Mechanical cutting of the tile edges after firing to achieve precise dimensions. It allows installation with a minimal joint (1.5–3 mm). Non-rectified tiles require a wider joint.

V1 to V4 (shade variation) — V1 uniform appearance, V2 slight variation, V3 moderate variation, V4 substantial variation between tiles. It is an aesthetic criterion, not a quality rating.

Slip-resistance classes (CTE DB-SUA 1)

They are determined by the Rd slip-resistance value, according to UNE-ENV 12633:

In swimming pools, Class 3 applies to areas used by barefoot users and to the pool floor where the depth does not exceed 1.50 m.

Our ADL finish

ADL is the name we give to our anti-slip versions: a surface developed to provide greater grip, certified as Class 3 according to UNE-ENV 12633:2003. It is the recommended option for terraces, porches, bathrooms with flush-to-floor showers and pool areas.

Complementary German classifications

In addition to Rd, many technical datasheets also include:

• DIN 51130 (shod ramp test), R9 to R13 — R9 dry interiors, R10 wet areas, R11 outdoor areas, R12–R13 industrial and food-processing areas.
• DIN 51097 (barefoot ramp test), A / B / C — A changing rooms, B showers and pool surrounds, C submerged stairs and access ramps into the pool.

They are not equivalent to Rd and do not replace CTE requirements; they provide complementary information.

Tile classification code

The Ceramic Tile Guide defines a code summarising a tile’s suitability for use. Format: mechanical / slip resistance / additional characteristics.

1st — Mechanical characteristics (1 to 8)

A higher number includes all lower categories.

2nd — Slip resistance (0 to 3)

It corresponds to the CTE classes shown in the table above.

3rd — Additional characteristics

Hygienic use: premises requiring intensive cleaning or the use of aggressive chemical agents. Outdoor use: areas exposed to frost, including cold rooms.

CE marking and DoP

Ceramic tiles are covered by the harmonised standard UNE-EN 14411 and bear CE marking with a Declaration of Performance (DoP) in accordance with Regulation (EU) No 305/2011 on construction products. The DoP certifies the declared performance values and accompanies the product supply.

The substrate

It must be flat, clean, dry, stable and fully cured. Typical waiting times before tiling: cement screeds and mortars, approximately 4 weeks; renders, 2–3 weeks. On deformable substrates or substrates subject to foreseeable movement, it is advisable to increase the joint width and reduce the tile size.

Adhesive (UNE-EN 12004)

Additional designations: F fast setting · T reduced slip · E extended open time · S1 deformable · S2 highly deformable.

General rule: due to its low water absorption, porcelain tile requires C2 for outdoor areas, façades, underfloor heating and large formats. White body wall tiles on interior walls can be installed with C1. If the specification indicates C1, a higher-performance adhesive can always be used.

Double buttering — adhesive applied to both the substrate and the back of the tile. Essential for large formats, outdoor applications, tiles with a textured back and floors subject to high loads. The notched trowel should be drawn in straight lines to allow air to escape; on rectangular tiles, the adhesive ribs should run parallel to the shorter side.

Mechanical fixing — for wall tiles larger than 60 × 40 cm or weighing more than 25 kg/m², mechanical fixing is required.

Joints

Structural joints. They must coincide with the joints in the substrate, continue through the entire installation including the decoupling layer, and be at least the same width. They are finished with a durable elastic material or profile.

Juntas perimetrales. At every junction between flooring and vertical elements (columns, partitions), and between wall tiling and adjoining surfaces. Minimum width 1.5 cm, continuous and extending down to the substrate. They are usually concealed by the skirting. They may be omitted in rooms smaller than 7 m² with a side ratio below 1:1.5.

Omitting them is one of the most common causes of tile lifting.

Movement joints. They divide large tiled areas. Minimum width 5 mm, cutting through the tile and adhesive down to the substrate.

It is recommended to divide the surface into rectangular sections with a 1:1.5 ratio. In areas subject to large temperature fluctuations or vibrations, increase the number of joints.

Tile joints. The gap between adjacent tiles. A minimum joint is considered to be between 1.5 and 3 mm, while installation with joints starts at 3 mm. Below 1.5 mm, the grout cannot penetrate correctly and the tiles may come into contact: this should never be done. Minimum joints require rectified tiles.

Grouting (UNE-EN 13888)

Cementitious grout is not recommended in premises that are frequently cleaned with aggressive products, or for food-processing or healthcare applications. Where a compressible filler is used in the joint, the minimum grout depth must be 6 mm.

Initial cleaning after installation

After grouting, a cement film remains on the surface. In most cases, a diluted acidic solution (commercial vinegar) is sufficient. Specific post-construction cleaners with higher concentrations are also available and should be used with caution.

Precautions that prevent most damage:

• Never carry out acid cleaning on newly installed tiles. Acid reacts with uncured cement and may damage the joints or leave insoluble compounds on the surface.
• Wet the surface with clean water before any chemical treatment, to prevent the grout and substrate from absorbing the product.
• Rinse with water immediately after the treatment.
• Always test the product on a hidden area before applying it more widely.
• Do not use solid detergents containing abrasive particles on glossy surfaces.

Routine maintenance

Clean periodically with water or a diluted neutral detergent solution. Nothing else is required: as a glazed product, it does not need waxes, sealers or water-repellent treatments.

On floors: avoid abrasives, impacts and punctures. Avoid contact with strong acids (hydrochloric acid). Do not allow standing water to remain, as seepage may affect the floor structure.

On walls: avoid rubbing and punctures. Do not hang heavy items from the wall covering without anchoring them to the partition, taking care not to drill into concealed services.

Black or greenish stains: these are mould caused by moisture. Clean them as soon as possible with household bleach, first testing its effect on a spare tile, and identify and eliminate the source of the moisture.

Stain removal table

Frequently asked questions

Can I use white body wall tiles on the floor?

No. Its water absorption exceeds 10%, and its breaking load is much lower than that of porcelain tile. It is a product designed for interior wall cladding.

Can porcelain tile be installed on walls?
Yes, without any problem. For large formats or tiles weighing more than 25 kg/m², mechanical fixing should be considered and C2 adhesive with double buttering should be used.

Why glazed?

Because the glaze is the layer that defines colour, graphics and surface performance. It allows marbles, stones, concretes and woods to be reproduced with a level of definition that through-body colour cannot achieve, while sealing the surface so that no subsequent sealing or stain-protection treatment is required.

Rectified or non-rectified?

Rectified tiles allow a minimal joint (1.5–3 mm) and a more continuous appearance. Non-rectified tiles require a wider joint. The joint should never be less than 1.5 mm.

Can I mix boxes from different batches?

No. Shade and calibre must be consistent throughout the same installation area. Check the packaging before starting.

How much extra material should I order?
Between 5% and 15% depending on the installation pattern, plus an additional 1% reserve for future replacements.

Is ceramic tile suitable for underfloor heating?
Yes. It is one of the best finishes due to its thermal conductivity. The key is the installation system: deformable adhesive and compliance with the commissioning protocol.

Does it require any treatment after installation?

No. Glazed products do not require sealing, wax or water-repellent treatment. Only the initial post-installation cleaning is required to remove the cement film.

Why do tiles lift?

The most common cause is the absence of perimeter joints. Other causes include insufficient movement joints in large tiled areas, uncured substrates and insufficient adhesive.

Is an R11 rating sufficiently slip resistant?

R11 (DIN 51130) is indicative. In Spain, the applicable requirement is the CTE DB-SUA 1 class obtained through the pendulum test (Rd). Our ADL finish is certified as Class 3 according to UNE-ENV 12633:2003.

Can it be installed over existing flooring?

It is possible in certain cases, provided the substrate is properly prepared and a suitable adhesive is used. The flatness, adhesion and stability of the existing flooring must be assessed.