CERAMIC TILEWORKS, FLOORS AND WALLS IN BATHROOMS AND TOILETS
1. Relevant standards
EN 14411 (2016), Ceramic tiles - Definition, classification, characteristics, assessment and verification of constancy of performance and marking
EN 12004 (2017) Adhesives for ceramic tiles-- Part 1: Requirements, assessment and verification of constancy of performance, classification and marking
EN 13888 (2009) Grout for tiles-- Requirements, evaluation of conformity, classification and designation
The material should meet the following requirements:
- The packages, in which the tiles have been delivered, should be marked according to the standard EN 14411;
- Length and with tolerances, straightness of sides and rectangularity, surface flatness and surface quality should be in line with standard EN 14411;
- The calibre and shade of tiles, that will be installed in the same room, should be the same;
- Small colour differences, according to EN 14411, are acceptable. The surface of the tiles must be free of cracks, holes, stains, bubbles, thickening or devitrification of the glazed surface;
- For medium size ceramic tiles, minimum thickness of wall tiles should be 7mm, for floor tiles-- 8,5mm.
There are no specific requirements according to the method of production, both extruded (code A) and dry-pressed (code B) ceramic tiles are acceptable, with glazed (code GL) or unglazed (code UGL) surface.
Water absorption (E) should be E= 6% for floor tiles. There are no special requirements for wall tiles.
According to resistance to surface abrasion, floor ceramic tiles should belong to the class 4 according to ISO 10545-7 (also referred to as class PEI IV or class G).
The floor tiles should satisfy the coefficient R9 of slip resistance (according to DIN 51130).
Regarding to chemical resistance, tiles should be classified as:
GA for resistance to household chemicals
GLA for resistance to low concentrations of acids and alkalis
GHA for resistance to high concentrations of acids and alkalis
Warranty should be two years on material. Contractor is to submit manual for maintenance and cleaning.
Adhesives for ceramic tiles should be classified, according to EN 12004, as class C2.
Grout for tiles should be classified, according to EN 13888, as
- class CG 1W for tiles that have water absorption capacity >3% and formats that provides surface of less then 900cm2;
- class CG 2W for tiles that have water absorption capacity =3%.and surface area =900cm2.
Chemical compatibility must be guaranteed with the material of the tiles
The grout mass should be such that it prevents the colour change and the formation of mildew.
The product must be solvent free, must not be labelled as toxic, must have a complete Safety Data Sheet and all the carcinogenesis compounds and volatile organic compounds emitted by the product must be measured. The materials should comply with GEV’s EMICODE EC1/EC1PLUS classification or similar.
All materials should be approved through the Submittal process.
Prior to the start of works on the installation of ceramic tiles, the Contractor is obliged to check whether the room has been prepared, as follows:
- whether the substrates (cement screed, plastered walls) are prepared for the installation of ceramic tiles, i.e. cleaned, straight, without cracks and other damage. Irregularities in the substrate should be remedied by impregnation, mechanically (by scraping), by installing waterproofing, by installing additional layer of mortar or adhesive over the metallic net (rabitz) etc. If none of the methods can be applied, the substrates should be removed and a new one made:
- whether all electrical installations, mechanical installations and installations of water supply and sewage systems have been finished and tested;
- whether frames for joinery are built in;
- Is waterproofing completed and tested;
- whether all equipment which should be installed before the installation of ceramic tiles are installed (drains, profiles for shower cabins and the like). The height of the waterproofing, unless specified otherwise in design documents, must be not less than 30cm above the upper edge of the bath or 75cm from the upper edge of the shower bath.
If the room is ready for the installation of ceramic tiles, the Contractor should, in writing, request the Supervisor to approve the commencement of works.
The temperature in the room, during the installation of the ceramic tiles, must not be less than 10°C. This temperature should be in the room also 7 days after the completion of the ceramic tiles installation. After the work is finished, it is not allowed to move people in the room for a period of 3 days.
Ceramic tiles to be installed by adhesive. Adhesives to be prepared and used strictly according to the instructions of the manufacturer of the material. The space between the ceramic tiles and the substrate must be completely filled by adhesive, no cavities are allowed. The width of the joints should be 3mm, unless otherwise specified in the design.
The wall with ceramic tiles should be flat and vertical. Inclinations in the floor, if any, should be in line with the design. Internal corners in the rooms, unless otherwise specified in the design, should be 90°. Particular attention should be paid to the corners where baths or tops with washbasins will be installed.
The joints should be uniform and geometrically accurate. The edges of the ceramic tiles on the outer corners must be mitered.
The Contractor should first install ceramic tiles on the walls and then on the floors. Leave the lowest row of tiles on the walls for installation after the laying of ceramic tiles on the floors. Unless otherwise provided by the design, the ceramic tiles on the walls must be placed so that the end tiles at both ends of the wall are equal, and not less than 1/2 of the tile. It is not required that the joints of the walls and floors coincide.
In the sanitary rooms, the wall tiles should be placed over the bathtub or shower tubs and special profiles, acrylic silicone or plastic kit should be used for the connection. Unless otherwise provided by the design, distance between edge of the drainage spot and wall must be at least 20cm. It is not permitted to lay parts of entire tiles around wall installations outlets.
Upon completion of the laying of ceramic tiles on the walls and floors, tile surfaces shall be thoroughly cleaned in accordance with manufacturer's approved cleaning instructions and the Contractor should check again the performed works, particularly whether the position of all installation outlets are done as per design. Before they start with grouting, the Contractor has to invite the Supervisor to inspect the performed works and approve the beginning of grouting in writing.
Joints should be properly filled with grout mass. Grout mass to be prepared and used strictly according to the instructions of the manufacturer of the material.
The ceramics tile installer is obliged to fill the joints between ceramic tiles and drains.
4. Supervision and measurement of works
After the material is delivered to the site, the Supervisor should check whether the material is delivered undamaged, it is packed and marked as required by the relevant standards and whether it is properly stored.
Supervision is obliged, before the beginning of the works, to check that the Contractor has verified that the rooms are ready for installation of the ceramic tiles, visually check the condition of the rooms and approve the commencement of works.
During the execution of the works, Supervisor is obliged, on daily basis, to visually check the premises where the ceramics are installed. Upon completion of the installation of ceramic tiles in each room, and before the start of grouting, Supervisor is to verify that the Contractor controlled the executed works and to visually check the quality of the performed works. Verticality of the walls, horizontality or inclination on the floors and corners in the room to be checked by the mason's bubble level and square. Special attention should be paid to accuracy of the installation outlets position.
The executed works to be calculated per sqm of cladded area. Areas not bigger than 0.5 sqm, that are not cladded by ceramic tiles, should not be subtracted from the total quantity. The cladding of the heights of up to two rows of tiles, should be calculated per linear meter.
Classification according to the manner of production:
Group A Extruded ceramic tiles
Group B Dry pressed tiles
Classification according to water absorption:
Ia Water absorption less than 0,5%
Ib Water absorption from 0,5 to 3%
IIa Water absorption from 3 to 6%
IIb Water absorption from 6 to 10%
III Water absorption more than 10%
Classification of adhesives (EN 12004)
Cementitious (C), adhesives made from a mixture of hydraulic binders, aggregates and chemical additives. They may be either a one-component type, which means they just need to be blended with water, or a two-component type, which means they are blended with water and/or latex.
Dispersion (D), a mixture of organic binders dispersed in water polymers with organic additives.
Reactive (R), a mixture of synthetic resins which harden through a chemical reaction (components A and B).
Class 1: Normal adhesives
Class 2: Improved adhesives
Class F: Fast-setting adhesives;
Class T: Reduced slip adhesives;
Class E: Adhesives with extended open time:
Class S1: deformable adhesives (for cementitious adhesives only);
Class S2: highly deformable adhesives (for cementitious adhesives only).
PEI 0 Glazed tiles in this class are not recommended for application on floors.
PEI 1 Appropriate for covering floor surfaces where people walk only in shoes with soft soles or barefoot, without dirt which scratches the floor surface (for example, residential bathrooms and bedrooms without direct access from outside).
PEI 2 Appropriate for covering floor surfaces where people walk in soft or plain shoes, usually with small quantities of dirt which scratches the surface (for example, rooms and living rooms in houses and apartments, with the exception of the kitchen, the doorway and crowded rooms).
PEI 3 Appropriate for covering floor surfaces where people often walk in plain shoes, with little dirt which scratches the floor (for example, residential kitchens, halls, corridors, balconies, terraces). This does not refer to exceptional footwear, for example - studied boots.
PEI 4 Appropriate for floors with normal movement of people with slightly more dirt which scratches the floor (for example entrances, public kitchens, hotels, exhibition and retail space).
PEI 5 Appropriate for floors with constant great natural load and presence of dirt which scratches (for example, public surfaces such as commercial centers, airport interior rooms, hotel lobbies and application in industry).
GEV (a German body which monitors emissions from construction materials).
Classification of grouts (EN 13888)
Types of Grouts:
Cementitious Grouts CG
Reaction Resin Grouts RG
Classes of Cementitious Grouts:
Normal Grout 1
Improved Grout 2
Characteristics of Cementitious Grouts (optional):
Fast-Setting/Drying Grout F
High Abrasion Resistance Grout A
Reduced Water Absorption Grout W
Determination of resistance to chemicals - This testing determines the tiles' resistance to the effect of household chemicals, salts in the water of a swimming-pool, acid, base and resistance to the effect of a 'pencil with HB hardness'. Depending on the type of chemicals and resistance of tiles, they are divided in the following classes:
Household chemicals and salts in the water of a swimming-pool
GA with no visible effects
GB small changes in the appearance or if the tiles did not pass the testing with a 'pencil with HB hardness'
GC siginificant changes
Acids and bases (low concentrations)
GLA with no visible effects
GLB small changes in the appearance or if the tiles did not pass the testing with a 'pencil with HB hardness'
GLC siginificant changes
Acids and bases (high concentrations)
GHA with no visible effects
GHB small changes in the appearance or if the tiles did not pass the testing with a 'pencil with HB hardness'
GHC significant changes
If facade walls are covered by ceramic tiles or walls in a room where the temperature is significantly lower than in the adjacent room, it should be checked if the water vapour diffusion has been calculated in design.