Slippery Rock Gazette

Bob Murrell 

M3 Technologies

Photos by Bob Murrell

We have discussed lippage before, but it is such a reoccurring issue that I thought revisiting the topic would be of value. Lippage, not to be confused with the back-talk from your significant other, or quite possibly even your mom, lol, is the height difference between one tile and next.

Even with the high tech tile setting systems of today, to install a totally lippage-free floor is practically impossible. Of course, having proper grout width helps with the precision of the install. Grout lines that are too wide can increase the margin of error for lippage. Remember, for marble and other dimensional stone, the grout lines should typically be no larger than 1/8” or even 1/16”. Wide grout lines normally require the addition of sand for strength and stability too, and we all know that is a no-no, for most finished stone installations.  

Above, left: Moderate lippage on a limestone floor. Above, right: Severe lippage on a marble floor.

People, meaning customers, who do not know the significance of lippage, will tell you there is no height difference in their floor installation. They are not trying to deceive you, they honestly just don’t know what to look for. Of course, neither do some general contractors. Most anyone, who has never had to remove lippage, doesn’t understand the significance of it. 

As restoration professionals, we know that irritating sound from diamonds going clackety-clack on the uneven tiles. We know that dreaded sound means more work and potentially much more work. It also means more costs, both to you and therefore the customer, too. Lippage is typically the most expensive step in the restoration process, not to mention the fact that it also means there are now more steps in the process as well.

Breaking out the metal bond diamonds is always a major commitment. Depending on the severity of the lippage, it will determine the step at which you start. Trust me, if you have severe lippage, starting at a 70g metal bond diamond will make for slow going. For example, let’s say you go ahead and go for the gusto and start with a 50 grit or somewhere close to that. Starting with a 50 grit or coarser metal means that you will probably need to go with either a 70 grit metal or 50 grit transition resin diamond next. So you easily end up doing two steps before you ever reach 100 grit or 120 grit. Hence the reason for both the added time and cost.    

There are ways to cheat the lippage removal system in certain situations and I’ll discuss this in a moment. The terms picture framing or widow pane come to mind for those who have experience with lippage removal. This is especially true for darker floors and definitely most black floors. The lighter colored stones are better with regards to disguising and blending the picture framing. You see, the high spots are not necessarily the main problem with lippage. The low spots typically remain in the original finished condition, meaning they never received wear like the surrounding surface. These low spots, which show up as the picture framing areas, can stick out like a sore thumb.   

If you have ever had the request to convert a previously polished marble floor to a honed floor, lippage really becomes an issue. The picture framing just can’t be blended or matched like when polishing. This sticks out so bad that contractors will try anything to get rid of it, even turning to the use of strong acids to etch and remove the polish in these low areas. This operation of going from polished to honed can be very tedious. It is best to go ahead and remove the majority of lippage, through grinding, in this scenario. 

Deciding on the type of metal bond diamond to use in the initial heavy grinding of the lippage removal process can be a key component as to how much work you will have to commit to. There are many diamonds that can accomplish this task, but doing it with as little of an invasive scratch pattern is the trick. You see, some metal bond diamonds can leave behind a very aggressive scratch pattern. That is why you probably wouldn’t want to use a 16 grit or 24 grit concrete-type diamond. These super aggressive metal bond diamonds are used for coatings removal or heavy rectifying situations where the scratch pattern left behind is not consequential.   

I recommend starting as high in the grit sequence as possible, to avoid heavy scratch patterns. The 3-inch tooling metals from M3 Technologies, Inc. are excellent. They have the beveled edges, which help prevent the chipping of tiles and with gliding over high spots, and believe me you don’t want to glide over the high spots. They also have excellent life expectancy.

One of my favorite metal bonds for lippage removal are the Flexible Electroplate metal bond diamonds from M3 Technologies, Inc. I have found that using these, in conjunction with the 3-inch spacers (for added cushion), can make short work of moderate to mild lippage removal applications. They also come in 5-inch” diameter, which works great on a hand tool for help with those pesky high and sharp edges. These thin, yet fairly aggressive little pads work very fast and are available in grits from 40 grit to 600 grit.

Above, left: Severe lippage removal using a hand tool with ELF5 Flexible Metal 40 grit. Above, right: Restored polished marble, honed in place.

Now as promised, let’s discuss the situations where lippage removal is not feasible, whether by lack of budget or whether it is simply not a completely necessary action. On most lighter colored marble, you may be able to just hone (meaning 220g, 400g, and 800g), feathering out after each step, prior to polishing. It all depends on your ability to polish and match the original finish. Heavy traffic lanes and bad etching are usually the only areas that normally require any significant honing. All other areas of marble, travertine, terrazzo, onyx, and other calcium-based stones should respond well to Majestic 5X, XXX, or Marble Polishing Compound.  

As always, I recommend submitting a test area to confirm the results and the procedure prior to starting a stone or hard surface restoration or maintenance project. Remember to use your smartphone to take plenty of before and after pics! Also, the best way to help ensure success is by partnering with a good distributor who knows the business. They can help with technical support, product purchase decisions, logistics, and other pertinent project information.

Bob Murrell has worked in the natural stone industry for over 40 years and is well known for his expertise in natural stone, tile and decorative concrete restoration and maintenance. He helped develop some of the main products and processes which revolutionized the industry, and is currently the Director of Operations for M3 Technologies.