These professionals provide the consumer, whether commercial or residential, with the choice of a better and more qualified tile installer.he July/August issue of TILE was to have been the last installment outlining the features and benefits of the Advanced Certifications for Tile Installers (ACT) testing program, which included Large Format Tile and Substrate Preparation, Membranes, Mortar (Mud) Floors, Mortar (Mud) Walls and Shower Receptors. However, due to the popularity of this program and the ongoing need for additional craft skills to be assessed, the ACT Steering Committee has commissioned two additional tests: Grouts and Thin Porcelain Tile (TPT). This article will focus on the Grouts testing program for which the curriculum and testing module were just completed at the end of July.
The ACT tests are a combination of an open book written test, which is administered online and taken at home or in the office per the installer’s schedule, while the hands-on test is provided at regional locations around the country. Upon registration, the installer receives a packet consisting of the ACT Statement of Intent, Study Guide, Instructions to the Installer (hands-on test guidelines), Installer Critical Points (items that, if not completed according to industry accepted methods and standards, constitutes a failed test), the TCNA Handbook and the ANSI Specifications. These documents provide the installer with all the study materials necessary to take both the written and hands-on tests.
Ceramic and natural stone tiles are aesthetically pleasing and highly functional surfaces. These tiles can be a manufactured product such as ceramic,porcelain, metal and glass,or a stone product that is quarried out of the ground and processed. Both products offer a durable surface generally used for covering floors, walls, showers, backsplashes and countertops.
Grouting materials are used in conjunction with these tile products to enhance their beauty. Today, many manufacturers produce over 30 different colors of grout to complement almost any design requirement. Functionally, grout fills the space between the tiles, which helps to accommodate size and thickness variations in ungauged stone as well as out of square tile (wedging). Basically, grout is used to fill the joints, making them hygienic, while protecting the tile’s edges from damage during use.
As you can see, grout installed in a tile, stone or thin brick installation is both cosmetic and purposeful. Unfortunately, in the course of a tile installation being completed, some contractors employ the least experienced and lowest paid worker to complete this task. While well intentioned, this individual usually does not have the wherewithal to complete this “finish” aspect of the job. In the course of my training in tile work, one of my instructors said, “You can take a mediocre tile installation and save it with some top shelf grout and detail work. Conversely, you can take a high-quality tile installation and ruin it by using haphazard grouting skills, which most likely will be rejected by the end user.” This is not to say that the industry encourages mediocre work, but points to the importance of high-quality grout work, sealant joints and detailing. This is the reason that ACT is including the testing of properly completed grout and movement joint installation in the program.
The Grouts test focuses on the proper selection, preparation and installation of three grout types as categorized by the American National Specifications Institute (ANSI), including A118.3, Chemical Resistant, Water Cleanable Tile-Grouting Epoxy; A118.6 Standard Cement Grout and A118.7 High Performance Cement Grout. An additional aspect of the test, which is many times overlooked or eliminated because they ruin the tile pattern, is expansion joints. With very few exceptions, all tile, stone and thin brick installations must include these spaces that provide for anticipated movement. This test determines if the installer has selected, prepared and installed the movement accommodation and expansion joints as detailed in the TCNA Handbook under section EJ171.
Selecting the most suitable grout type is crucial to a long-lasting and beautiful tile installation where the owners are not only happy with the new installation, but will be for years to come as the grout continues to perform as expected. There are numerous aspects to consider when selecting a grout product, including intended use of the space or facility, submersion or immersion potential, the size of the grout joint, chemical exposure, exterior weather conditions, owner expectations and the overall cost impact. Grout joints should be full and have a smooth texture with no tooling marks, consistent color, no crazing or cracking, no efflorescence and no haze or residue on the tile surface.
One additional facet of the Grouts test, which may not come to mind immediately, is thin brick. Since thin brick is not installed in the same manner as conventional full-sized brick, the joints need to be filled and tooled to make them weather resistant, functional and pleasing to the eye. This process, while different than a conventional method of using a grout float, requires skill and expertise.
In order to meet these expectations, many job specifications require a jobsite mockup or demonstration board, which shows the specified tile, grout joint size and grouting material installed for approval by the owner, architect or general contractor before the installation begins. This establishes both customer and installer anticipations of the grout being used and the finished result. This is especially true when grouting over tile types that may be unfamiliar to the installer, including exotic materials such as unfamiliar natural stones, glass tile, decorative and other specialty tiles.
Even if the job does not require a mockup to be provided, it is a good idea to do so. This eliminates the “five o’clock surprise” by the consumer saying something such as: “That is not what I picked,” “It is not the right color,” “I thought the joints were going to be much smaller,” or “What are those dark specks that seem to be imbedded into the tile that are the same color as the grout?” A bit of offense in this regard will save countless headaches later on.
With stone and glass tiles, the installer must be certain that the surface will not be scratched or damaged by the sand in the grout. Some glass tile manufacturers require unsanded grout to prevent scratching on smooth glass tile surfaces. Consulting the Natural Stone Tile Selection and Installation Guide in the TCNA Handbook — along with always following the glass tile manufacturer’s product recommendations and tile installation guidelines to the letter — will avoid these issues.
When polished or unpolished unglazed porcelain tiles are specified, the surface of the tile may exhibit surface staining if not protected when the grout is applied. Even though the tile is a true porcelain with very low porosity (.5% or less), the tile surface has very small microscopic pores that can “trap” grouting materials and other contaminants such as a #2 lead pencil used to number the order of the tiles for installation. It can be very difficult, and in many cases impossible, to remove these stains. In the accompanying photos, you see the lead pencil marks noting tile # “10” on the face of a polished porcelain tile. In the photo of the light blue polished porcelain tile, one side was protected with a grout release while the other side was left unprotected. When a charcoal cement grout was applied, the grout darkened the tile surface significantly and can’t be removed. To avoid these problems, pre-seal the tile with a suitable grout release or penetrating sealer. But prior to using any products of this type, always consult both the tile and the sealer manufacturer for proper product use and recommendations.
In commercial applications where architectural specifications are in place, the selection of the grout type has already been determined. However, on the residential side, the installer is many times called on to supply the appropriate material based on the job requirements. Either way, the installer needs to know what product to use and where to use them.
An epoxy grout meeting ANSI A118.3 normally provides high bond strength, impact and chemical resistance, and because of its low porosity (generally .5%), improved stain resistance. These characteristics make it very desirable and long lasting, but for these benefits to be realized, the installer again must be adequately trained and tested. Epoxies by nature are significantly different than cementitious grouts and need a skilled mechanic to do the work. For example, the installer in this photo demonstrates the towel dragging technique, which clears the grout residue from the tile face, resulting in a clean and smear-free finish.
Cementitious grouts designated as Standard and High Performance Cement grouts have been on the market for many years and have served the industry well. The grouts in the Standard category are suitable for walls and floors in ordinary use while the High Performance grouts provide improved characteristics, including increased bond strengths, flexural strength and lower water absorption, which functions well especially in cold winter environments.
The ACT Grouts hands-on test in its Evaluation Score Sheet incorporates several Critical Points, that if not completed properly, the entire test fails. This list includes the following critical items:
• Was the appropriate grout selected for the job?
• Was the cementitious grout powder mixed with the manufacturer’s recommended amount of liquid?
• Was additional liquid added after the final mixing was completed?
• On cementitious grouts, is the grout flush to the top of the square edge tile or to the bottom of a cushion-edged tile?
• Was the entire unit of epoxy grout mixed according to the manufacturer’s recommendations?
• Is there any grout contaminating the perimeter movement or expansion joints?
• Was the cement-based grout washed improperly?
• Were the epoxy grout joints within the ANSI requirement of 3/64 inch below the face of the tile?
• Was the completed work clean and free of any haze or residue?
• Were the movement accommodation and expansion joints prepared properly?
• Was the correct sealant used in the movement and expansion joints?
• Was the perimeter movement joint left open and clean (no grout)?
You can see from this lengthy list that the grouting process is significantly more involved than smearing grout over the face of the tiles and walking away. Upon passing the ACT Grouts tests, the mechanic has proven that he or she has the skills and knowledge to handle the job correctly the first time.
When the grout job calls for a professional (and it always should), hire and use the person that meets the Qualified Labor designation and has the credentials to back it up. Hiring or using the lowest paid and least qualified individual will provide exactly that — a cheap and unacceptable mess. Think about it.