Problem Solver #1: Porcelain Tile -Factory Applied Wax Coatings on the Surface

Tile/Stone/Grout Care and Maintenance: Problems Solvers with Nick
We are excited about adding a new blogger to our MAPEI Tech Talk line up, Nick Valenti.  Nick will be addressing specific issues that arise during the installation, care and on going maintenance of tile, stone or grout as part of his ‘problem solver’ series—featuring sealers, finishes, cleaners and specialty problem solver products. 

It is becoming a more common practice for porcelain tile manufacturers to apply a wax coating to the surface of unglazed, honed and polished porcelain tile. This nano (nanotechnology) coating is applied at the factory, before the tiles are packaged and shipped.  The purpose of this coating has been debated since it first started showing up on imported porcelain tile.  One concept is that the coating is applied to protect the tile surface from mars and scratches that may occur during transportation.  These treatments are commonly referred to as “transit coatings”.  Another concept is that the treatment acts as a sealer, filling in the micro-pores of the porcelain, thus protecting the tiles from staining during the grouting process. Whether or not the treatment is beneficial in either circumstance is uncertain and has mixed reviews.   Not all porcelain is created equal. By doing some pre installation homework before grouting, installers can avoid time consuming and costly call-backs for grout haze issues. When issues do arise, selecting the correct products to correctly remove waxes and grout haze will expedite clean-up, minimizing effort and cost. 
 
It is often left up to the installer to determine if this wax treatment is present and provides any benefit during the grouting process.  To determine if the porcelain tile you have chosen has been treated with this wax, visually inspect the tiles by looking at the surface at various angles of light.  The wax will appear as a cloudy haze that smudges easily.  This is easiest to identify on polished porcelain.  Another way to identify this treatment is to place several droplets of water onto the tile surface.  If the droplets show a pronounced beading effect and don’t spread, this may indicate the presence of waxes or sealers, but is not always a reliable indicator. The best source of information is the supplier or the manufacturer of the tile.

If you choose to leave the wax coating on the surface, instead of applying a sealer to aide in releasing the grout, perform a grout release test in an inconspicuous area or on a mock-up of the same tile being installed. The wax haze may not appear on unglazed and honed porcelain tile until after the tiles have been grouted and the grout residue has been removed.  If the tiles dry hazy and dull after the grouting and clean-up processes are completed, it may be an indication that the wax treatment is present. Use Ultracare Abrasive Surface Cleaner  to remove this wax haze.
 
During the application of this factory applied wax, it will run down the sides of the tiles and dry.  This wax coating interferes with the grout adhering to the sides of the tiles after being floated into the grout joints, allowing some grouts to slump out of the joint and making installation difficult. It is Mapei’s recommendation to remove any wax treatments on vertical tile installations before grouting.  If the unglazed porcelain is honed or polished, it is recommended to seal the tiles after removing the wax and before grouting.  Remove the wax coating using Ultracare Abrasive Surface Cleaner and seal the tile using Ultracare Penetrating Plus SB Stone & Porcelain Tile Sealer, or Ultracare Grout Release, before grouting. 
 
If, after grouting and normal clean up procedures have been followed, the tiles exhibit signs of dried grout residue on the surface, Mapei offers a variety of Ultracare Problem Solvers to efficiently remove the grout residue. For cement based grout, such as Keracolor S & Keracolor U; use Ultracare Cement Grout Haze Remover. For ready mixed grouts, such as Flexcolor CQ, use Ultracare Heavy Duty Stone, Tile & Grout Cleaner or Ultracare Epoxy Grout Haze Remover. For epoxy grouts, use Ultracare Epoxy Grout Haze Remover.  If a haze is still present after chemically cleaning, use Ultracare Abrasive Surface Cleaner.