Q: The finish on the kitchen floor tiles in our condominium is wearing off in many areas. The tiles are holding up well otherwise, but the wear is widespread and unsightly. I've used different cleaning products over the years, but even discontinuing bleach products hasn't stopped the apparent wearing away of the finish. The box says it's Ergon-engineered stone (40-by-40 rettificato, gres fine porcellanato). I don't want to replace the floor. Is there a way to strip the finish and redo it? Is there a company that might do it for us?
A: The box may say "engineered stone," but tiles with that label from the Italian company Ergon differ from most engineered stone tiles sold in the United States. The kind typically sold here is made of crushed stone bound together by polymer resin or Portland cement. There's also "engineered tile," which is vinyl made to look like stone. But Ergon tiles are porcelain, a mixture of quartz sand, feldspar and clay fired at a very high temperature.
"The 'engineered stone' part means that the Ergon porcelain tiles are made with a higher grade of ingredients compared to standard porcelain tiles," Michael Montorsi, owner of M2i and a manufacturer's representative for Ergon, said in an email. The high-temperature firing results in "a fully vitrified impervious material that is actually harder than granite but that can look like stone, wood, marble, metal, concrete or other," he wrote.
In the picture you sent, the lighter-color areas appear to be where the finish is coming off. In a follow-up interview, Montorsi acknowledged that — but said he believes that's not what's really going on. Ergon tiles don't have a surface finish that can come off and reveal a lighter color underneath, he said. The company does produce tiles with different "finishes," but these are textural differences, not coatings. "It can be shinier, rougher; one is smoother and others are more grippy," he said. "It's all physical texture."
Montorsi said he thinks the light areas instead show where your cleaning has been effective. "What is showing through is the real tile and the dark areas are dirty tile," he said. "Can you please have the homeowner try and use Scrubbing Bubbles (avoid the grout lines if not epoxy) or Barkeeper's Friend (no bleach) and some hot water and the green side of a [Scotch-Brite] pad and some elbow juice." He suggested scrubbing for two or three minutes.
Or, he said, you could try using a Mr. Clean Magic Eraser with Bar Keepers Friend. The Magic Eraser, like the Easy Erasing Pad from Scotch-Brite (each about $1 a pad at Home Depot), is made of melamine foam, which has the scrubbing power of fine sandpaper but open pores that hold on to the loosened grime. Scrubbing Bubbles Citrus Bathroom Grime Fighter is $3.48 for a 32-ounce bottle, and Bar Keepers Friend, a powdered cleanser, is $2.18 for a 21-ounce can. Scrubbing Bubbles contains several ingredients that combat dirt and mineral deposits; S.C. Johnson, the manufacturer, lists ingredients at whatsinsidescjohnson.com. Bar Keepers Friend contains oxalic acid, which breaks down mineral deposits and other grime. Wear rubber gloves while using any of these products, especially for the length of time it will probably take to scrub as thoroughly as Montorsi recommends. Because you mention having used various cleaning products over the years, perhaps at one point you used a product intended to leave a shiny coating on vinyl floors, and that finish is what trapped dirt.
If cleaning in one of these ways doesn't restore a uniform look, Montorsi said, contact the store that supplied the tile. If the tiles were installed before you purchased the condo, you might need to track down the contractor. Or you could contact Montorsi (630-539-4470; email@example.com), and he can put you in touch with a local dealer, whom you can ask to take a look.
As for whether it's possible to apply a new finish to your floor, there are companies that specialize in recoating bathtubs with acrylic urethane spray. They advertise that the same process can be used to refinish porcelain tile. But though these coatings may be fine for walls, or even for a floor in a lightly used bathroom, it doesn't seem like a wise solution for a kitchen floor, which gets a lot more traffic.
It would be better to see whether you can work out a remedy through a dealer — if it comes to that.