grinding natural stone, lippage removal, honing, northern virginia stone restoration

Grinding, Honing, & Polishing

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Every profession uses common terminology. Stone restoration is no different. For floor work here are the three most common terms you will hear:

 

Grinding – This process is most common in Europe, where the installation process for natural stone floors is a bit different. As the natural stone tile is installed, the grout is placed on all 2-3 sides of the tile. It is then butted up against adjoining tile. This leaves excess grout sticking up out of the tile. It also creates a more solid bond, as there is no worry about jamming the grout all the way to the bottom of the joint. The installation then cures for 5-7 days. Then, a floor machine with rough diamond attachments is run along the the floor. This “grinds” the floor and excess grout down. The result is a perfectly flat floor. It makes the floor easier to clean, as nothing can get stuck in the grout lines, because the grout lines are even with the natural stone. It is also more pleasant to walk across on bare feet. You don’t feel the difference between the grout lines and the natural stone.

 

In the US, it is associated with poorly installed marble or travertine. If one tile is higher than the adjacent tile, that is called lippage. If there is too much lippage, typically greater than a dime, this is out of specifications. Instead of tearing up the floor, it can be ground down and flattened. After grinding, the floor looks terrible. Additionally, depending on the quality of the install, some grout may have popped out. This is a result of the tile installer failing to push the grout down far enough. This can be easily patched, but may delay the project a day. There is no shine, and there are visible marks from the diamonds cutting the floor down. This leads to the next step honing.

 

Before discussing honing, let’s discuss the benefits of grinding first:

 

  1. Gives you a perfectly flat floor, much more pleasant to walk on with bare feet
  2. Makes cleaning easier, there is no chance for dirt to get in the grout lines
  3. When polished, gives a classic mirror like look

 

Honing – This step gives the floor its clarity. After grinding, there are large cut marks from the diamonds. Honing removes these marks by leaving smaller cut lines. It is similar to using finer sandpaper on wood to get a smoother finish. After grinding, the honing process typically starts at 50 grit. If no grinding is done, the honing process usually starts at 220, and goes to 1800. If you are looking for a “matte”, flat, or semi-gloss finish, honing is required. This removes the scratches and leaves very little to no reflection.

 

If the stone is honed, the pores are left more open versus honing to a high grit and polishing. This is where a high quality sealer truly makes a difference. We offer premium solvent based sealants preventing staining and watermarks.

 

Typically, travertine, limestone, and slate are kept at the honed level. This gives a more rustic look for the floor.

Polishing – The final step in most natural stone installations, this gives the stone its reflection, or mirror like finish. Using a polishing compound, the heat and pressure make the top layer of the stone turn into a mirror like finish. While polishing can be the shortest step in duration, it gives the biggest wow factor to a floor.

 

If you are interested in learning more about grinding, honing, or polishing your floor, give us a call at 571-488-1892. Thank you for reading.

travertine, tile floor, stone restoration, fairfax, virginia, great falls

Waxing Natural Stone Floors

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A problem on natural stone floors we often encounter is black grout lines, black spots in the floor and general dinginess. This is from wax being applied to the floor. Never apply wax to the top of a natural stone floor. Unfortunately, this is a mistake too many homeowners have made. Let’s discuss why this happens, and how it can be fixed.

 

First, there are some floors where applying wax is appropriate. In the kitchen, wax used to be applied on linoleum floors. The floors looked great, but it was a very labor intensive process. The result was a no-wax linoleum floor. This is probably the reason we see wax applied in kitchens. Wood floors used to be waxed and buffed. This has fallen out of use in favor of more permanent polyurethane finish. On the commercial side, there is Vinyl Composition Flooring, or VCT tile. This is in many grocery stores. It looks great when waxed. Unfortunately, many janitorial companies think applying wax to any floor is a good idea.

At first, it looks like a great idea! It will make the floor look shiny and highly reflective. Then people begin using it. High traffic areas get walked on, and dirt gets trapped in the wax. The grout lines turn black first, then the pores of the stone turn black. Finally, nearly all of the shine fades away. The result are the black grout lines, black spots and dinginess explained above.

The problem is compounded when more coats of wax are applied to the top. They temporarily lighten up the black grout lines, but then turn black again.

  •  GROUT TYPE

    First we need to determine if the natural stone floor has sanded or unsanded grout. If it is unsanded grout, the wax can be stripped from the floor. This will make the floor look better instantly. The grout lines will return to their original color.

  •  UNSANDED GROUT

    Once the wax is stripped from the grout, the floor can then be honed and polished.

  •  SANDED GROUT

    For sanded grout, the fix is more complex. Sometimes the wax can be stripped from sanded grout, other times the wax is stuck in the grout lines. The typical result is removing 90% of the wax, and having discolored grout lines on the remainder.

  •  ULTIMATE FIX

    The ultimate fix removes all the sanded grout with a grout saw. Then the grout is reapplied and allowed to cure. Then we can grind down the floor, hone and polish.

     

    Stone Cleaner:

    A pH neutral stone cleaner maintains a floor best. I recommend against using a spray mops on natural stone floors. The spray chemical has very small amounts of wax in it, and this builds up over time.

     

    If you are in Northern Virginia, and you think wax was applied to your stone floor, give us a call at 571-488-1892 to discuss.