Friday, 29 May 2015

What are PEI ratings for tiles really?

PEI (Porcelain Enamel Institute) ratings help you determine the hardness and durability of tile. This is crucial because not all tile can be used in all areas. PEI ratings act as a kind of shortcut to figure out where the tile can be installed. Tile that experiences much foot traffic should be harder and denser than than that receives no foot traffic. Tile installed on a wall receives no foot traffic and, in fact, almost no wear of any kind.

From a technical perspective PEI ratings are actually determined by a measurement of Abrasion Resistance (EN154) measured on a machine like the one above which counts the number of revolutions under a standard abrasive load. When the tile shows damage the revolutions are counted, (from 150 to 1500+) this gives the PEI rating. 


The method was developed on the basis of the claim that the degree of deterioration of a floor should not determined by the reduction in its thickness, but the visible difference in appearance between the worn surface and the unworn surface, assessed at a defined distance under standard conditions of lighting. It is important to stress that, for the same degree of abrasion, wear is invariably more visible on dark surfaces. For this reason, the PEI value is shown in tile catalogues as the requirement for the individual article, rather than for the series as a whole which may have lighter and darker tiles. 

PEI 1: Up to 154 revolutions
No foot traffic. Wall use only in residential and commercial applications. For use on very light-wear areas, using soft footwear.

PEI 2: 300, 450, 600 revolutions
Light traffic. Very light-wear, mainly bathrooms and areas using soft footwear. Wall use and bathroom floor applications.

PEI 3: 750, 900, 1200, 1500 revolutions
Light to moderate traffic. Average domestic homes. Countertops, walls, and floors for normal foot traffic.

PEI 4: 1500+ revolutions
Moderate to heavy traffic. All residential applications as well as medium commercial and light institutional.

PEI 5: 12000 revolutions
Heavy to extra heavy traffic. All residential and heavy commercial and institutional foot traffic, stores, entrance halls, shops & hotel floors.

From this scale you can see the numbers of revolutions required in the testing method to abrade the tile. But some tiles, classed as PEI 4, could possibly only withstand abrasion up to 2000 revolutions while others could withstand abrasion far in excess of 1500 in fact as much as 96 000. This is why PEI 5 is being introduced.

The new ISO product standards (Project ISO TC/189) envisage the introduction of a further class of resistance, class PEI 5, to which tiles meeting the following conditions at 12 000 rpm will be assigned:
1. Alterations must not be visible at a standard distance.
2. The surface subjected to abrasion must pass a cleaning test with the staining agents chromium green in light oil, iodine in alcohol solution, and olive oil.

This new class, therefore, also takes into account the effects of abrasion on susceptibility to soiling. The introduction of class PEI 5 fulfills the need to highlight more clearly, in relation to performance, the superior characteristics of ceramic glazes for technical applications developed in recent years.

Monday, 18 May 2015

12 Questions to ask when investigating a laminate flooring complaint.

The following checklist questionnaire is a guide as to what might have gone wrong with Laminate flooring. Remember installation errors are the primary cause of failure. This is intended for retailers and suppliers in particular. 
  1. Was a qualified, professional installer used? If not look very closely at the installation procedure. 
  2. Was a new screed laid? If so how long was it allowed to set & dry? The full time could be up to 14 days.
  3. Was the subfloor properly level and without irregularities?  The floor should have a minimum flatness of 0.015 or 15mm variance over 10m.
  4. If the subfloor was tiles, were the grouting joints filled? If the surface is tiled, grout lines deeper than 3mm and wider than 5mm must be filled.
  5. Was the flooring allowed to acclimatize for 48hrs in the room at a temperature 18-26 degrees C?
  6. Was sufficient space left around the edges for expansion? 8-10mm
  7. Were expansion gaps installed for large areas and between rooms? 7-10m
  8. Is the room exposed to lots of direct sunlight? Does the room become very hot? The room or floored area should never reach a temperature over 38 degrees C. Exposure to temperatures exceeding 38 degrees will void the warranty. The product is not suitable forinstallation in conservatories or areas exposed to excessive direct heat such as fully glazed sun-facing areas.
  9. How was it cleaned?  Use of excessive water/mopping?
  10. Did moisture enter via walls or floor? Moisture could reach the subfloor from below or by migrating through the walls.  To prevent moisture from penetrating to the sub-floor you may put silicone around the perimeter of the installation in such a way that it does not affect the ability of the floor to float within the expansion spaces.
  11. Were furniture glides used to prevent scratching?
  12. Was the pH of the subfloor tested? A combination of high pH levels (alkali) and high moisture content of the underlying floor can leads to problems. Concrete is naturally highly alkali but should not exceed a pH of 9 for a successful installation. Acid levels should not be below pH 6.
All the best,
The Link International team

Tuesday, 5 May 2015

We're back from Florida, Chicago next!

We're all back from Orlando, Florida. Coverings 2015 is over but we'll be back for Coverings '16 in Chicago next year! Above is a stunning image of the famous 'Cloudgate' sculpture in Chicago.
Meanwhile here's a preview of our very latest design ink-jet tile design 'Cloud'. This hi-resolution 60x60 tile has a subtle horizontal and vertical patterning that resembles woven papyrus. Suitable for both floors and walls it will be produced in grey, beige and cream.

Contact us for enquiries.
All the best,
The Link International team and KREM.