01. What is water absorption?
Water absorption is an indication of the porosity of a ceramic tile. The lower the porosity the less water a ceramic tile will absorb, with consequent higher mechanical resistance and better technical characteristics. The ceramic revestments are classified in accordance with their water absorption, respecting the norm NBR 13817.
| Type of Product |
Water absorption groups |
Water absorption (%) |
| Porcelanato |
BIa |
< 0,5 |
| Gres |
BIb |
0,5 < AA < 3,0 |
| Semi -gres |
BIIa |
3,0 < AA < 6,0 |
| Semi - porous |
BIIb |
6,0 < AA < 10,0 |
| Porous |
BIII |
> 10,0 |
02. What is the Resistance to Surface Scratching / Abrasion?
Abrasion Resistance - PEI
|
Resistance to wear
through abrasion |
0 |
use only on walls |
1 |
very low traffic |
2 |
low traffic |
3 |
medium traffic |
4 |
high traffic |
5 |
very high traffic |
It is the wear caused by abrasion from the scraping of the soles of shoes with dirt or other abrasive material on them - such as sand and earth, etc. - over the enameled surface of the ceramic revetment.
This wear, over time, can become so evident that the characteristics of the enamel can be completely altered, forming paths of wear. Resistance to abrasion is very important for floors where people or vehicles circulate.
This is not important for walls, as the ceramic revestment doesn't suffer this type of wear. Abrasion resistance is commonly referred to as PEI.
03. What does PEI mean?
PEI is an acronym of the institute that created the method of measuring Surface Abrasion: the Porcelain Enamel Institute.
04. What is Deep Abrasion Resistance?
It is the method used to verify the resistance of non-enameled ceramics - one example is Porcellanato Técnico. This method involves a rotating steel disk (at a constant speed) rubbing against the surface of the piece being tested with a fine aluminum powder between the disk and the surface to provoke wear. The quantity of wear removed from the piece determined its Deep Abrasion classification.
05. What is the Scratch Resistance - MOHS?
This indicates the hardness of a piece's ceramic enamel. One material will leave a scratch on another if is harder. To stop revestments being scratched by materials present in the environment its enamel must be harder than those materials.
This characteristic is very important in environments in contact with the outside.
Example: Sand from the beach is composed basically by quartz, therefore when exposed to this sand it is unadvisable to use revestments with a MOHS of less than 7.
Hardness of some natural materials:
| Material |
Mohs scale |
Material |
Mohs scale |
Talcum |
1 |
Semi-precious stone |
6 |
Plaster |
2 |
Quartz |
7 |
Calcite |
3 |
Topaz |
8 |
Fluoride |
4 |
Corundum |
9 |
Apatite |
5 |
Diamond |
10 |
06. What is Stain Resistance?
This characteristic indicates the ease of cleaning a ceramic revetment. This is related to the type of enamel used.
The Norm NBR 13.817/1997,based on ISO 13.006/1995, classifies the ceramic revestments in accordance with their ease of cleaning, as shown in the table:
| Class |
Can be Cleaned with: |
5 |
Hot water |
4 |
Common detergent (pH between 6.5 and 7.5) and water |
3 |
Strong detergents (pH between 9.0 and 10.0) and water |
2 |
Special products |
1 |
Cannot be cleaned |
07. What is Expansion by Humidity?
Porous ceramics absorb water - hydration. With the passing of time, this absorbed water increases in volume - expansion. To absorb water and expand in volume, a ceramic piece tends to loosen from the tile cement.
Itagres' ceramics, enameled or otherwise, have practically zero expansion by humidity. Therefore, correctly installed ceramics from Itagres will not loosen through expansion by humidity.
08. Can high-shine products be scratched?
Ceramic revestments with brilliant surfaces, such as the polished porcelanatos and gres, are susceptible to scratching, requiring special care through protection during installation by keeping the environment clean and free of abrasive materials and correct daily maintenance by removing abrasive residues that are dragged across the floor by shoes. The use of doormats and rugs at entrances helps in preventing scratching. Remember there is a class of product for each type of environment.
09. What is a lapidated product?
A lapidated product is one that is given a special type of polish. It is part-polished, that is, the polish is carried out in accordance with the texture of the ceramic, on the highest parts of the ceramic face. This means some regions on the revetment shine while others don't. The shine is less brilliant than that achieved by a full polish. The result is that of stone partly worn through time.
10. Why is resistance to freezing important?
Water that penetrates ceramics when freezing expands, possibly damaging the piece. This a characteristic that depends on low water absorption and, consequently, on low porosity. The Itagres Porcelanato line is highly resistant to freezing as it has very low coefficient of water absorption.
11. Double Fixing: When to do?
Pieces equal or greater than 30cm x 30cm require double fixing / cementing as they are lightly convex in shape, meaning the centre of the underside needs to be completely filled with tile cement when being installed straight onto the substrate.
To confirm that the seating of the tile is correct, lift the piece to ensure that the reverse is totally filled with tile cement.
12. What is the maximum time for removing grout?
The correct method is to work leaving the minimum grout residue possible. The cleaning of any residue should be carried in the first 15 minutes following application. Many jobs are dirtied by leaving grout on the tile face. Consult the manufacturer's instructions for the maximum time to remove residue.
13. What is the minimum joint width for tile installation?
The joint width depend on the type of revestments:
- For rectified products, ITAGRES recomends 2mm joints
- For non-rectified products, ITAGRES recomends 5mm or 1/100 of the produtct's size.
14. What is Porcelanato?
Porcelanato is a revetment created and developed in Italy that is now produced in Brazil by companies at the vanguard of this technology. The term porcelanato comes from 'porcelain' and refers to ceramic products produced from selected primary materials that are submitted to a heat treatment of above 1,200 ºC, resulting in a product with extremely low water absorption < 0.5%. The tile body is compact, homogenous, dense and vitrified. The tile is distinguished by its high abrasion resistance and freezing resistance.
15. What is the difference between Porcelanato Técnico and Enameled Porcelanato?
Porcelanato Técnico is pressed as a single body. There is no enamel in its composition, just mass and coloring. This tile can be Polished or Natural. It is superficially decorated with colored veins from natural stone.
Enameled Porcelanato has the same technical characteristics as the Porcelanato Técnico, but with enamel as a finish. It is classified by its PEI. Being enameled it is distinguished by its high resistance to staining.
16. Can a Porcelanato stain?
Porcelanato on the "Polished" face has a completely flat and porous surface, as it has passed through the process of polishing to achieve its high sheen. Therefore, with these micro-porous parts caused by the polishing process, it is naturally subject to some form of dirt adhering to the ceramic, as also happens with natural stones that are plain and porous.
To guarantee the aesthetic appearance and hygiene a daily clean with water and chlorine-based soap must be carried out. For dirt that is difficult to remove, consult Itagres Customer Support Service.
Durability and conservation depends on an adequate cleaning routine and care with products which may cause stains, as in the case of acids for example. Do not use home made cleaning products which contain acids.
17. How to correctly install Porcelanatos?
Porcelanatos require no techniques different to the conventional method of installing ceramic revestments, but certain care must be taken to ensure perfect installation, such as employing a professional qualified for the service, the use of equipment in a perfect state, the use of materials appropriate for porcelanatos such as ACIII tile cement and epoxy grouting. Maintain a clean environment during the installation to avoid the presence of abrasive materials.
18. How to grout anti-slip flooring?
Revestments with a friction coefficient greater than 0.4 - Classification 2 - are known as anti-slip flooring. The enameled surface is rougher and because of this, during the grouting the residue will tend to stick more on the surface, meaning that once dried the removal of any residue will be very difficult. Itagres recommends cleaning the residue within the time recommended by the grout manufacturer. This cleaning is carried out with a damp sponge on all the revetment borders. If necessary, carry out a second clean with the damp sponge.
This work can be helped by the application of a liquid wax on the ceramic surface. This allows the removal of excess grouting, however it is important that the wax doesn't run into the joints as this will inhibited the adherence of the grout.
19. How to grout Porcelanatos in composition (chessboard layout)?
Porcelanatos with polished surfaces, just like natural stones, can present micro-porosity in cases where grout residue occasionally remains. Itagres recommends the use of colored grouts that match the color of the product. For example for a light-colored porcelanato, use light grouting and for dark-colored porcelanato, use dark grouting. In the case of a white/black combination use an epoxy grouting that does not allow the retention of residues in the micro-porous pieces.
20. How should a ceramic piece be changed?
To change broken ceramic pieces without compromising the rest of the covering, you must:
- Remove the grouting around the broken piece with a knife or a scraper;
- Mark the piece with an 'X";
- Tap the center of the "X" with a punch and hammer, removing all loose pieces and tile cement;
- Apply white latex glue or tile cement to the underside of the new piece and seat, keeping the joints regular. Wait to dry before grouting as normal.
21. What to do with grout residue that wasn't removed from the ceramic pieces correctly during installation?
It is recommended that water and diluted vinegar are mixed in a bucket and the pieces cleaned with a brush with nylon bristles.
.
WARNING: Use stronger acids only in the last instance and after contacting the Itagres Customer Support Service, as stronger acids may attack the revestments, removing the top enamel layer to leave the surface porous and liable to retain dirt in the future.
22. What is efflorescence and how to avoid it?
Efflorescence is a defect that can occur in any revetment, mainly in hot and humid areas. It normally appears in the form of a clear viscous liquid in the joints and, in critical cases, through the holes that it produces in the enamel. Deposited salts from the rendering, cement and tile cement are almost always present which migrate to the revestments' surface. This can be avoided by following some tips:
- Use ceramic revestments with low water absorption properties.
- Make the cement work impermeable.
- Leave the wall rendering and floor substrate to completely 'cure'.
- Avoid using strong acids when cleaning revestments (principally with yellow coloring), as these attack the grouting and the enamel. If it were unavoidable, dilute the acid in a weak concentration, testing before use on a separate revetment.
- Use impermeable grouts to avoid the migration of efflorescence to the surface of the revestments.