The New Generation of Grout
Nowadays, there are a myriad of different grouts on the market. From cement-based and epoxy grouts to single-component and pre-mixed mortars, each serves a specific purpose. But what really constitutes an effective grout? And which type is the best to use in a particular environment?
FCI had the chance to sit down with a large group of professionals within the industry to learn more about these growing grout technologies and why they’re so important. Below, we only begin to scratch the surface of what these products are capable of.
“We are seeing advances in all types of grout technologies,” said Steve Taylor, director of architecture and technical marketing for Custom Building Products. “Cement-based grouts cure faster to allow early traffic on the tiled assembly, finer aggregate for narrower grout joints and improved stain resistance. Epoxy grouts have been formulated to stand up to harsh environments, where high chemical-resistant was specified in the past. These industrial-grade epoxy grouts are being used in commercial kitchens, where they are exposed to hot cooking grease and strong cleaners during maintenance. Single-component grouts continue to gain acceptance because of their ease of use and high stain resistance.”
While cement-based and epoxy grouts continue to evolve, offering more appealing technical characteristics, manufacturers are seeing a rise in high performance (HP) and ready-to-use (RTU) grouts. “The newest trending technologies on the market are high performance grouts which meet ANSI 118.7,” said Michele Swiniarski, market manager of ceramic installation systems at Bostik. “Grouts in this category offer lower absorption rates, higher tensile and flexural strengths.” “High performance grouts with more features and benefits, as well superior physical properties, have been a game changer for the tile market for the last few years,” added David Mowery, business manager for TSIS color products and UltraCare at MAPEI Americas. “With the advent of large-format tile (LFT) and specialty tile like glass mosaic and high-end porcelain wood-look tile dominating the designs, the architect, contractor and homeowner are demanding a high-end grout category to accentuate these design choices.”
Although there are many different HP grouts on the market now, according to Laticrete, its recent developments allows for a longer shelf life, aiding both designers and installers. “While most products on the market must be disposed of after a year, the longer shelf life with products developed by Laticrete will allow distributors and contractors to store them for an extended time,” said Sean Boyle, vice president of marketing, North America, at Laticrete.
While HP grouts are seemingly stealing the spotlight, RTU grouts are another popular choice. “Pre-mixed, resin grouts are one of the most recent evolutions in products,” said Alan Kin, head of technical sales at Texrite. “The pre-mixed or ready-to-use grout addresses installer issues that are inherent in Portland cement grout. Part of this change and improvement obviously eliminates the variation in grout mixed being too fluid or soupy at the jobsite, where the ready-to-use grout is factory-mixed to the precise slump or workability.
“A huge gain has been in color consistency; no longer is the grout dependent on cement hydration and/or crystallization,” Kin went on to explain. “The new resin technology simply requires air drying. Uneven color shading or splotchy grout color is no longer a factor. The mineral surface whiting known as efflorescence is no longer a factor with the elimination or replacement of the Portland cement binder with waterborne resins. If repairs of grout are needed, the same color repair will match the pre-existing grout color without the use of a grout colorant. The finished, installed grout continues to reap benefits to address owner issues by providing an integral, pre-sealed grout that is topically and internally sealed.”
“Although ready-to-use or single component grouts have been available for some time now, advances in technology have improved the performance of some ready-to-use products now on the market to the point where they can be used for exterior installations or submerged applications,” added Tom Plaskota, technical support manager at H.B. Fuller Construction Products. “Previous versions would not hold up in these demanding environments.”
New products on the market
Most grouts and mortars are developed to cater to certain products—whether large-format tile, porcelain tile or glass tile—so understanding their proper usage is essential to the life of any installation. “Today’s single-component, epoxy and even cement-based grouts are much easier to install and keep clean,” explained Taylor. “Through improved formulations and installation techniques, Custom Building Products is able to offer grouts that allow easy filling of the joints and simple cleaning off the face of the tile. Training videos are helping train installers in the proper way to install and maintain grout. Combining new grout formulations with better installation training has reduced the time required to grout a typical tiled assembly.”
“Ardex grout technology has focused on the installer and making the application and cleaning of the grouts easier,” said Seth Pevarnik, director of technical service at Ardex Americas. “Ardex cementitious grouts have a creamier consistency through the use of finer sands and unique polymer formulations and allow the installer to cover larger areas. And with larger areas, not having to clean as frequently is critical. The grouts are formulated to set hard in the joint, but not stick to the tile as found with most traditional grouts.
“Typically, epoxy grouts are frowned upon by installers because they are very sticky and difficult to work with and apply, but Ardex’s epoxy grout technology delivers a unique, very creamy, easy-to-apply consistency,” he went on to say. “Like their cement counterparts, this consistency delivers fuller, stronger grout joints.”
RTU and HP grouts are boasted for their easy cleanup, which is a major benefit of the trending products. “The cleanability of this grout category far exceeds traditional Portland cement grouts and offers the simplicity of installation that both professionals and DIY’ers alike can appreciate,” said Mowery. “Aside from cleanability, today’s grouts have transcended to higher levels of stain resistance, longevity in the joints, color consistency and ease of installation. Some of the newest versions of RTU grouts are offering translucent and metallic finish looks to complement popular mosaic tile designs.”
“Pre-mixed or RTU grouts are easier to use from the no-mixing aspect,” said Kin. “They are also easier and time/labor efficient for not having to wait and return to the jobsite later for sealing.
“This process is integrated into the grouting stage,” Kin went on to explain. “Spreading and cleanup of the pre-mixed grout from the surface has a different manner of sectional grout and tile surface wiping. Sectional ‘20-minute’ grouting working areas are to ‘be grouted and then cleaned.’ Although different in manner, the new grout and resultant grout color is not going to have shade or uneven color which was somewhat problematic to Portland cement grout installations. The grout colors are not going to be prone to being splotchy from excess moisture coming beneath tiles or setting mortars. With larger tile installations and compressed work schedules, the grout can be installed sooner without fear of color shading. The same would be true if the grout was to be interrupted and restarted; the grout color will consistently color-match. Additional or add-on grout and tilework or repair work will also be color-consistent. The extra benefit of no wasted grout is that the excess or extra unused grout can be sealed tightly and saved for another job or another day.”
“Several of the advanced performance grouts have the strength and stain resistance of epoxy grout, but offer the easy application and cleanup of traditional cement-based grouts,” added Plaskota. “There is virtually no difference to installing these grouts vs. traditional cement-based grouts.”
Bostik, which introduced a HP sanded cementitious grout technology, known as HyDrix, is also on the forefront when it comes to new developments. “This advancement in materials science creates a dense internal matrix which allows Bostik to offer the most durable, easy-to-use, cement-based grout available,” explained Swiniarski. “This highly compacted matrix results in a superior grout joint which is resistant to the penetration of liquids and most staining agents, highly resistant to efflorescence and extremely dimensionally stable.”
After all is said and done, one may wonder, what are the benefits of these new formulas? Do they offer contractors and installers something older products don’t? “The newer grout and tile-setting products are being developed to address the changing tile sizes and composition,” stated Kin.
“Changes in tile sizes, with gains in porcelain tile and glass tile manufacturing, are requiring better handling of the installation processes that can be accomplished with better/newer grouts and tile-setting mortars.
“Making grout more trouble-free to a broader skill level of the installer is the goal,” Kin went on to explain. “Setting materials are so often judged or selected according to the price of the bag. The newer, better performing bonding products can properly bond under more adverse conditions at the time of installation and upon service life. Both installer productivity and durability of the bonding product should be matched and/or increased with the increasing tile’s size and improvements in the tile’s density/composition increase.”
Taylor and Plaskota echoed Kin’s comments, stating how customers expect these grouts to be as durable as the tile they’re installing. “The latest generations of grouts fit this bill,” said Taylor. “They cure hard and durable and nearly match the stain resistance of the tile.”
“With superior stain resistance, many new modified cement grouts do not need additives and sealers,” added Plaskota. “Even years after installation, they will not need to be sealed.”