Choosing an Adhesive for Large-Format Porcelain Stoneware: Classes, Markings, Mixing Technology

Laying tile of 60×120 cm, 120×240 cm or larger is not just a process of sticking. It is the creation of a strong, monolithic and flexible “sandwich” that can withstand enormous internal stresses, temperature changes and constant mechanical load. The heart of this system is the right adhesive.

Using the wrong adhesive mix for large format means guaranteed problems in the future. At M-STONE in Kyiv we use exclusively premium-class adhesives, because we understand that the flawlessness and durability of our clients’ interiors in the Podilskyi, Darnytskyi, Sviatoshynskyi and other districts of the capital are at stake.

Decoding the markings: what do the letters on the bag mean?

The European standard EN 12004 classifies tile adhesives by two main parameters: the type of binder and additional properties.

Type of binder

C is cementitious. The most common type, it needs to be mixed with water.

D is dispersion. Ready-to-use pastes based on synthetic resins. Rarely used for floors.

R is reactive (epoxy, polyurethane). Two-component mixes with the highest adhesion and chemical resistance.

Additional properties (added after the digit 1 or 2)

1 is standard adhesion. Suitable for ordinary formats on stable substrates.

2 is increased adhesion. Mandatory for large format, porcelain stoneware and surfaces with low water absorption.

E is a “long open time”. The adhesive keeps its ability to bond for 30 minutes or more after application. Critically important for laying large tiles, when levelling takes time.

S is “slip resistance”. An adhesive of increased viscosity that does not let the tile slide during vertical installation (on a wall) or on a sloping surface. Mandatory for walls!

T is “thixotropy”. Increased slip resistance, an even more viscous consistency. Often marked together with S (ST).

F is “fast setting”. It gains strength faster, which lets you walk on the floor sooner.

C1, C2: deformation capacity. C2 means an increased ability to compensate for deformation of the substrate (for example a floor with heating, wooden substrates, old buildings).

So which adhesive do WE choose for large format?

For laying porcelain stoneware of 60×120 cm and larger on a floor we use adhesives of class C2E S1 or C2TE S1.

C2: increased adhesion and deformation capacity.

E: a long open time (you do not have to hurry when laying a large tile).

S1/T: slip resistance (even on a floor it is important that the tile does not “drift” after laying).

For installation on a wall (a kitchen backsplash, finishing a bathroom) we choose even more viscous adhesives of class C2TE S2 (increased slip resistance).

Mixing technology: why is it so important?

Even the most expensive adhesive can be spoiled by incorrect mixing. Here is our algorithm at M-STONE:

A clean container and water. We use a plastic bucket and clean cold tap water in the exact proportion set by the manufacturer.

Mechanical mixing. Only with a drill-mixer with a spiral attachment at low speed (300-600 rpm). Hand mixing does not give a uniform consistency, and “dry islands” remain.

Observing the pauses. After the first mixing to uniformity we let the adhesive “rest” for 5-10 minutes (the so-called “maturing period”). This is needed so that the chemical additives fully activate and the air bubbles escape.

Short repeated mixing. After resting we briefly mix the adhesive again without adding water. After that it is ready to apply.

No “topping up” with water! If the adhesive has started to thicken in the bucket, it must not be thinned with water: this irreversibly destroys its structure. A new batch must be mixed.

The slip test and correct application

Before starting work our craftsman always does a simple test: he applies adhesive to a small area and places a tile vertically. If it slides, the adhesive does not meet the S1/S2 marking or has been mixed wrongly.

Applying adhesive for large format is always double:

To the substrate: with a notched trowel (a 10-12 mm comb) the adhesive is applied and spread.

To the tile (mandatory!): in a thin layer the adhesive is “rubbed in” on the back of the tile with a flat trowel (so-called “buttering”).

A call to action:

Do not let unscrupulous craftsmen save on the most important component, the adhesive. Using a cheap C1 adhesive or, even worse, a classic cement mix under a large tile is a direct path to a second renovation.

M-STONE in Kyiv buys materials wholesale from official dealers, which lets us use premium adhesives at an adequate price and offer clients a full “material + work” package with a guarantee. We are responsible for every bag of adhesive used on your site.

Have doubts about the materials other contractors are offering you? Consult our experts! We will tell you exactly which adhesive your tile needs in your apartment or house in Kyiv.

Contact M-STONE for an exact estimate:

Phones: +38 068 100 27 96, +38 050 914 18 99

Email: [email protected]

Social media: Instagram (@mstone_kiev), Facebook (mstone.kyiv), YouTube (@M-Stone_Kyiv).

The current cost of work for your project can be calculated in the online calculators or confirmed by the manager: it depends on the material, the slab format and the condition of the substrate. The consultation is free.