Tile Troubleshooting: Tile and Stone Grout
I can still remember the first tile contractor I called on while I was working as a sales representative in Minneapolis all those years ago. "When you work with my customers, you tell the showroom sales assistants that you have two grout colors; white for walls and natural gray for floors." Actually, he was only half-kidding. Latex-modified grouts were just starting to enter the market, and the color selection was certainly limited at best. There was a great deal of fear in the mind of the contractor with some of the new pigments in the grout, and much of it was justified.
Today, we live in a different world. There has been incredible innovation in the tile manufacturing process, helping our industry to grow to levels that we thought unreachable just a short time ago. But we could not have gotten to where we are today if the Installation Materials Manufacturers hadn't also held up their end of the bargain. In my humble opinion, they have done a magnificent job. The improvements in mortars, membranes, tools, care and maintenance systems and grouts have played an equally significant role in ceramic tile's rise to the forefront of the floorcovering industry. That being said, we still have a long way to go, and grout, when improperly installed and maintained, can continue to be a thorn in our sides.
Common Grouting Problems and Today's Solutions
Too much water!
It sounds so simple, yet this is one of the leading causes of grout problems. The installer is not properly trained. Not all grouts are the same, and it is important to follow the manufacturer's instructions. Excess water in the mix evaporates, which leaves air holes that weaken the grout, causing porosity in its composition. Equally as important, and perhaps an area where significant improvement can be made, is the cleanup of the excess material. On the market today are great sponges and wash bucket systems that can speed up the cleanup process and improve the performance of the grout. Too much water used in this process can affect the color pigments causing discoloration or blotchy grout. In addition, the same mistake can lead to low grout joints, which can eventually cause chipping of the tile or stone edges.
Excess residue on tile that has dried
This is actually quite common, and with some materials, such as unglazed tile, porous stones, and terracotta tiles, it can be extremely difficult to fix. Some of these materials may be sensitive to chemicals and abrasion. You should consult with the grout manufacturer for their recommendations on cleaning a grout haze or film. Be specific about the tile or stone that has been used. It may also behoove you to talk to a technical representative from a company that specializes in tile and stone maintenance systems if the grout manufacturer doesn't specifically carry them.
It is also important to use a clean sponge when you are trying to get a haze off of the tile. This is a time where I have often seen excessive water being used, which can again cause discoloration as you wet the haze and wipe it back into the grout joints that are curing. Acid washing with sulfamic or phosphoric is often an effective means of removing a haze or film, but again a word of caution is to talk to the grout manufacturer first prior to the application. Always test the area in an inconspicuous area before commencing with the procedure.
Powdery or soft grout joints
The NTCA Reference Manual, a problem-solving guide for contractors, lists the following reasons as potential causes for soft or powdery grout. Failure to damp cure the grout. Many grout manufacturers call for the grout to be periodically dampened during the curing process, using kraft paper for up to 72 hours or by misting the joints.
Climactic Conditions. Too often this issue is overlooked. Pay close attention to the allowable fluctuations in temperature, both low and high, prior to mixing and applying the grout.
Old or Poorly Mixed Grout. Don't cut costs by using old grout that is in your warehouse if you have any concern about its pot life. It is not worth the risk. It is interesting to note that on some grout manufacturers instructions it calls for the blending of grout from different bags to avoid pigmentation differentials as well.
Improper Mixing or failure to slake grout. Use a mixer set around 300 r.p.m. and be consistent in this process. Allow the mixed grout to stand for approximately ten minutes before spreading into the joints.
These are just a few examples of common grouting problems that occur when we fail to follow directions. Speaking of following directions, it is actually quite interesting to read the installation instructions on the technical data sheets by the grout manufacturers. If you and your employees pay close attention to them and follow them to the best of your ability, I will be very surprised if you don't significantly decrease grout problems in the field. With the changes in grout technology taking place today, it has become even more important that you do so. Important notes I found interesting while studying the technical data sheets on the newest grouts introduced to the market include the following. Most companies offer Good, Better, and Best Products. Pay close attention to the specification and the application. There are times when an epoxy grout is essential to an installation, other times when it may be highly recommended, and certainly in many cases it would be overkill to even consider it for certain applications.
Many of the major grout manufacturers are now including mold, mildew and bacteria resistant inhibitors in their premium grout production. If you have installations in areas that are highly susceptible to moisture intrusion, I strongly consider using the premium technology offered today, as it is only pennies more in cost when you factor in the entire installation.
Epoxy is no longer to cause shingles or a break out in sweat. For years, the term epoxy sent chills down many a contractor's spine. Today, the improvements in this area are remarkable. Do not be afraid to consider epoxy grouts in the proper application.
Pay close attention to the care and maintenance of the system, as recommended by the manufacturer, and provide this vital information to your customer. This is an area that all of us can improve upon. Many times the consumer ruins a beautiful installation quickly by applying the wrong cleaners and waxes, and it is not their fault; it is ours.
New technology is now being introduced that is lighter than previous grouts and covers the same amount of square footage.
Final Things To Consider
Always pay attention to the limitations of the product. It is not in fine print in the technical data. This should be the first thing you look for. Ask yourself, and find the answer to: Where can I use the product, and where can't I?
Know Your Standards.
It is not the purpose of the article to cover the approved methods in our industry. However, it is essential that you understand where to find them. The American National Standards for the Installation of Ceramic Tile has specific standards developed for standard non-modified cement grouts (ANSI A118.6), polymer modified cement grouts (ANSI A118.7), modified epoxy emulsion mortar/grout (ANSI A118.8), and chemical resistant, water cleanable tile setting and grouting epoxy and water cleanable tile setting epoxy adhesive (ANSI A118.3). The manufacturer will reference these methods in their technical data sheets and inform you where their specific product should be classified. Contact the NTCA (www.tile-assn.com) or the Tile Council of North America (www.tileusa.com) for an updated version of the ANSI Handbook.