Design and laying

How to create a successful ceramic tile installation

The journey through of the world of ceramic tiles does not end with the choice of the most suitable type for the consumer’s requirements. Coloured, glazed or decorated, the tile does not guarantee a successful covering of a kitchen, square or building on its own. It’s at this point that the ability of knowing how to combine aesthetics and appearance and technique, design and execution, request and result, comes into play. Interior designers and architects, but also tile layers and consumers, must therefore prepare a project which, besides giving indications of appearance, also contain rules to follow during laying operation; rules which change according to the particular character that is desired for the floor or wall. This ability and professionalism allow to determine the correct width for the joints, the most suitable treatment for a terracotta floor, the best tile laying technique.
The durability of a tiled floor and wall also depends on the attention and care given to it. A bright tiling, which is regular and intact immediately after installation, will retain its quality and aesthetic characteristics over time thanks also to proper use and correct maintenance.

The design phase is an essential step in the creation of a correctly tiled surface. The tiling must be designed and specified in order to meet essential requirements.

  • Regularity and harmony (the surface must not have bumps or dimples).
  • Completeness (there must be no detached pieces or breaks).
  • Durability(the ability to withstand the challenge of time).
  • Safety (avoiding injury to the user).

This design phase is based on an interconnecting examination of the properties of the tiles, the area of intended use and the characteristics of the background to be tiled.

On the basis of the above, the designer will be able to establish the laying technique to adopt (using cement mortar or adhesives), any additional treatments to carry out on the background, as well as the width, layout and direction of the joints. The execution of the joints requires particular care; the aesthetic, technical and economic value of a tiled surface also depends on this, thus nothing can be left to chance: it is also important to establish the type of filling material to use. Finally, the movement joints are fundamental for the reliability and durability of the laying.

In order to prepare a successful project, it is necessary to analyse the characteristics of the surface to be tiled; this analysis in fact influences and determines the correct project solution to be adopted.

The factors to consider are the following:
  • the condition of the surfaces, an examination of the surfaces makes it possible to establish if cleaning treatments are necessary and to choose the most suitable adhesive;
  • the dilatometric behaviour, which may lead to stresses due to the expansion of certain layers;
  • the modulus of elasticity and sizing, which determine the behaviour of the structure under real load conditions;
  • the composition and structural arrangement, which indicates the location and dimension of construction joints, allowing for some movements between close parts in the structure;
  • the geometry of the surface to be tiled, which may affect the choice of tiles, their layout and the tile laying technique.

Tile laying techniques The binding layer or bedding may be composed of two different materials: the cement mortar and the adhesives.
With cement mortar laying, mixtures of cement (and/or lime), sand and water are used.
The mortar, applied in a "thick bed" (3-5 cm), forms a binding layer endowed with: good mechanical resistance, high rigidity, adequate adhesiveness, resistance to frost, and moderate resistance to chemical attack. The adhesives to use for laying may be cement- and organic-based.
The first are essentially pre-dosed cement mortars enriched with additives, which increase their ability to retain water. They are particularly suitable for being used in thin layers, and are not recommended for very flexible structures.
The organic-based adhesives are of two types: adhesives dispersed in water and reactive resin-based adhesives. The first have good flexibility properties, but their field of application is limited to interior wall coverings; reactive resins-based adhesives are recommended for environments and working conditions which require special chemical and mechanical properties of the tiling.

How many tiles to order and what tests to perform?br /> Once the project has been completed, it’s necessary to buy the chosen tiles. At this stage it’s important to follow a number of tips, which allow the purchaser to order the right amount and to check the correctness of the supply.

How many tiles to order?
To order the correct amount, it is necessary: to know the extension of the surface to be tiled and to have already selected the laying technique and laying design.
Considering even a top quality supply may contain some defective pieces, that some tiles will probably have to be cut or perforated during laying, and it is advisable to order 10% more tiles than the amount necessary for the surface to be tiled.

How to ensure an accurate supply?
In order to be able to check the supply, the order must include all identifying product data and the quality class. The supply is characterized by two important factors: tone and working size. The tone indicates the colour shade of the single batches of tiles. In industrial production, there may be small variations in colour; therefore, the tiles are controlled in the sorting phase and grouped in homogeneous classes according to colour tonality.
The working size corresponds to the manufacturing size, and just like tone, may vary in the production process. During the sorting phase, the tiles are grouped in lots with the same dimensions. Tone and working size are usually written on the packaging and in the shipping and accounting documents relating to the supply.
These two parameters should be carefully checked in order to carry out successful laying: tiles traceable to the same catalogue item, but of different tone and working size, should be considered as different products, and thus not suitable for tiling the same surface.

Care and professionalism are indispensable requirements in the laying of ceramic tiles, which is carried out through a series of fundamental operations which the installer is held to follow accurately.
He must: set up the laying building yard; check and control thestate and the measurements of the surfaces to be tiled; check the products to use; a floor with depressions or bulges, a wall which is not perfectly vertical, or defective tiles, will in fact damage the harmony of the covering with unsatisfactory visual effects.
Equally important are: the preparation and use of the bedding materials, and the application of the tiles, executed with different techniques: continuous or displaced joints, laying with open or closed joints.
The final result is in fact strictly related to the correct execution of all the different stages: a joint filled with unsuitable material or an imprecise application of the binding agents may in fact ruin the entire work.
A final essential aspect is the protection of the covered surface at the end of the entire procedure, in order to avoid damage in the intervening period between completion of the laying and its being put into use.

Floor tile laying with cement mortar:

  • preparation of the mortar, and thorough mixing;
  • spreading the mortar to the desired thickness;
  • levelling and tamping the mortar with a special rod;
  • spreading a thin layer of dry cement;
  • application of the tiles on the mortar bed, using spacers to create joints of uniform thickness;
  • wetting the floor, so that water can enter between the tiles;
  • vigorous and uniform beating of the floor, so that the tiles assume their definitive level position;
  • filling the joints with pre-selected material, using a rubber or plastic trowel. This operation must be carried out about three days after laying, to allow the mortar to harden;
  • cleaning the floor with a wet jute cloth, to remove all grouting residues. The floor must be kept damp and protected for a few days, avoiding any passage over it.
  • a final clean. It’s possible to remove any dirt and traces of cement using a suitable acid solution.

  • preparation of the supporting surface, which must be perfectly level, without cracks, and well cleaned;
  • preparation of the adhesive;
  • application of adhesive on the bed and laying of the tiles. In certain environments double adhesion may be necessary, applying a thin layer of adhesive also on the tile back (floating and buttering method).
  • filling of joints with the special rubber or plastic trowel;
  • cleaning with a damp sponge.
  • checking the evenness and verticality of the wall, as well as the levelness of the base;
  • after a careful cleaning, application of the adhesive with the special toothed trowel, following the same procedures as with the laying of floor tiles;
  • application of the tiles, starting from the floor, in order to define a horizontal reference. In certain environments double adhesion may be necessary, applying a thin layer of adhesive also on the tile back;
  • filling of joints with the special rubber or plastic trowel;
  • cleaning with a damp sponge.

Cleaning, protection and care of tiled surfaces
Besides good design and correct laying, the quality of a ceramic tile covering also depends on the care of the consumer.
Despite being a resistant material, the tile needs particular care with regards to maintenance, cleaning and protection.
The cleaning aspect requires a specific attention to detergents; the use of acidic and particularly aggressive substances may in fact damage both the tiles and the joints.
Moreover, it’s advisable to use abrasive instruments sparingly, especially in the case of glossy surfaces, being more vulnerable to visible scratches and marks.
Keeping the floor clean limits and prevents the presence of those types of dirt, like dust and sand, which can damage the tiles. As to protection, ceramic floors are only moderately resistant to impacts. Care must therefore be taken to avoid the falling of heavy objects, and to protect areas where objects may fall more frequently or easily.