European reference standards and classifications for tile adhesives and grouts

European reference standards and classifications for tile adhesives and grouts
Tile adhesives and grouts are subject to CE mark regulations and are classified in accordance with the parameters of the European standards  UNI EN 12004, 12002 and 13888. The letter "C" indicates a cementitious product. The letter "R" indicates a reactive resin adhesive. The letter "D" indicates a dispersion adhesive.
The standard UNI EN 12004 specifies that manufacturers must obtain certification from external, accredited authorities. The standards UNI EN 12002 and UNI EN 13888 specify that manufacturers need only provide a CE declaration of conformity based on internal tests performed by the manufacturers themselves.
• UNI EN 12004 STANDARD
UNI EN 12004 (Adhesives for tiles – Definitions and specifications)
UNI EN 12004 is a European standard which sets out the minimum performance requirements for ceramic tile adhesives. It divides products into three main classes as follows:
- C: cementitious adhesives divided into two sub-classes –
normal setting and quick setting
- R: adhesives based on reactive resins
- D: dispersion adhesives

For each of the three classes the standard lists the basic requirements for the following parameters:

Class C:
- Tensile adhesion strength (initial, after immersion in water, after exposure to heat, after freeze/thaw cycles) 
- Initial tensile adhesion strength (only for quick-setting cementitious adhesives)
- Open time

Class R:
- Shear strength (initial and after immersion in water)
- Open time

Class D:
- Shear resistance (initial and after exposure to heat)
- Open time

When a product conforms to the requirements specified in the standard it can be classified as C1 (normal setting), C1 F (quick setting), R1 or D1.

The standard also specifies 'optional' and 'additional' requirements as follows:

Class C:
- Optional characteristics:
Slip resistance
- Additional characteristics:
Enhanced tensile adhesion strength
Extended open time

Class R:
- Optional characteristics:
Slip resistance
- Additional characteristics:
Shear resistance after thermal shock

Class D:
- Optional characteristics:
Slip resistance
- Additional characteristics:
Enhanced shear resistance
(after immersion in water and after exposure to high temperatures )
Extended open time

When a product conforms to the optional requirements (i.e. slip resistance) the letter 'T' is added to the product classification. When a product conforms to one of the additional characteristics it can be classified as an enhanced product and marked as  C2, C2 F, R2 and D2 instead of C1, C1 F, R1 and D1). When a product has an extended open time, the letter 'E' is added to its classification.

The standard  UNI EN 12004 is a harmonised standard . The standard is mandatory and manufacturers must conform to this standard in order to obtain the CE mark for their products.
• UNI EN 12002 STANDARD FOR HIGHLY FLEXIBLE CEMENTITIOUS ADHESIVES
UNI EN 12002 (Adhesives for Tiles - Determination of Transverse Deformation for Cementitious Adhesives and Grouts)
UNI EN 12002 is a European standard which sets out the test methods to be used for classifying the flexibility of cementitious adhesives. The other standards for these products (i.e. UNI EN 12004 and UNI EN 13888) do not include measurements of flexibility.
This standard lists the degrees of deformability and specifies the test method to be used.
Products are classified on the basis of test results as follows:
S1 – Deformable
S2 – Highly Deformable

UNI EN 12002 is not a harmonised standard and therefore not mandatory for the CE mark. Conformity with this standard is not obligatory.
• UNI EN 13888 STANDARD GROUTS FOR TILES
UNI EN 13888 (Grouts for tiles – Definitions and specifications)
UNI EN 13888 is a European standard which sets out the performance characteristics for grouts. The standard divides grouts into two classes:
- CG cementitious grouts
- RG  reactive resin grouts.

For each of the two classes the standard lists the minimum requirements for abrasion resistance, flexing and compression resistance, resistance to freeze/thaw cycles,  resistance to water soak and linear shrinkage for both categories.

When a product conforms to these requirements it is classified as CG1 or RG.

For the RG class there are no additional performance requirements. For CG class products, on the other hand, there are additional performance requirements. Products which conform to these additional requirements are classified as CG2 with a suffix indicating the parameter as follows:

- CG2 Ar (grout with improved abrasion resistance)
- CG2 W (grout with reduced water absorption)
- CG2 (grout with improved abrasion resistance and reduced water absorption)

UNI EN 13888 Is not a harmonised standard and therefore not mandatory for the CE mark. Conformity with this standard is not obligatory.