If you’re a tile professional, you’ve probably heard of Gauged Porcelain Tile Panels/Slabs (GPTP). Not to be confused with Gauged Porcelain Tile (GPT), GPTP are a completely different product, encompassing the largest-sized tiles on the market.

GPT is defined as tiles that measure 1 x 1 meter (~36 x 36 inches) or smaller, while GPTP are equal to or larger than 1 x 1 meter. Around 2014, GPT was all the rave, but as time progressed and tile sizes continued to grow, GPTP emerged and has steadily gained traction ever since.

In 2017, after more than four years of cross-disciplinary industry collaboration and 4,000 hours of research, the Tile Council of North America (TCNA), which is responsible for devising material and installation standards for the tile industry, unveiled two new standards for the materials -- ANSI A137.3, the American National Standard Specifications for Gauged Porcelain Tiles and Gauged Porcelain Tile Panels/Slabs, and its companion, ANSI A108.19, Interior Installation of Gauged Porcelain Tile and Gauged Porcelain Tile Panels/Slabs by the Thin-Bed Method Bonded with Modified Dry-Cement Mortar or Improved Modified Dry-Set Cement Mortar.

The standards use the term “gauged” to cover a range of precise thicknesses that can carry different loads and be used in different ways, taking a similar approach to standardized wired gauged and gauged sheet metal. Two classes of gauged tile products are defined in the standards: those for wall applications, from 3.5 to 4.9 mm in thickness, and those for floor applications, from 5 to 6.5 mm in thickness.

ANSI A137.3 standardized the minimum required properties for the products themselves, while ANSI A108.19 standardized the methodologies for installing the products in interior installations by the thin-bed method with specific mortars.

Now, almost five years after the standards were established, handfuls of domestic and international tile manufacturers have created a demand for GPTP, pushing size boundaries, thicknesses and design possibilities. Unique properties have also been created for exterior use, so these larger-than-life tiles can be utilized for a variety of outdoor applications, as well as indoor.

GPTP Designs

One of the most popular types of materials GPTP strives to imitate is natural stone. Popular white marbles such as Carrara and Calacatta are some of the most popular GPTP designs requested by customers today, according to Ryan Fasan, technical consultant for Tile of Spain.

“For GPTP, as well as more standard dimensional tiles, the standout volume winners are variations of classic white marbles. Perhaps even more so in 12- to 20-mm-thick GPTP intended for countertops because of the massive livability difference afforded by moving to porcelain," he explained. "The fact that a client can have a white marble counter and fearlessly cook with acids and ferments like soy sauce, place a screaming-hot cast iron down without a trivet and even spill a glass of ruby red Rioja without repercussions is a huge performance gain over the authentic material. The other big differentiator versus a marble slab is the stone’s delicate nature due to the variance in mineral hardness that gives the iconic vein-structure precludes large-format slabs as the stone can crack under its own weight in larger dimensions -- not so with their porcelain counterparts.”

“Every market has a very specific taste. Different trends apply to different areas,” added Piergiorgio Mazzetta, CEO of Laminam. “In Europe, we are steering away from lighter colors toward darker colors, and concrete looks along with modern and contemporary finishes are more accepted. For now, North America is still riding the ‘white wave’ marble visuals, with solid whites as the biggest sellers. Polished and soft-touch finishes are in high demand, bookmatch is big and random veining graphics are very popular.”

Concrete-inspired looks are also a popular choice for customers all over the world. “Generally speaking, marble- and concrete-look GPTP seem to be trending the most at the moment,” said Rodolfo Panisi, CEO of Florim. “With that being said, each design has its sector and application where it’s more successful than others. For instance, the marble-look has great success in hospitality projects, whereas the concrete-look does very well in commercial spaces, and the terrazzo- and stone-look seem to perform greatly in healthcare and transportation projects. When developing new collections, it is very important to see what is in demand and trending in the market, but Florim needs to be innovative and creative as well.”

“Notwithstanding differences based on geographical area, in general, marble- and natural stone-effect slabs are widely used because the large size is ideal to show amazing veining designs and gives the astonishing effect of a large monolith,” added the Style & Design Center at Atlas Concorde. “Also, concrete and resin effects are very popular, first of all because they are trendy, but also because the huge size (and therefore limited number of joints) makes the space look wider.”

From Europe to North America

Although GPTP reign supreme in Europe, where they have been used for quite some time, they’ve been steadily gaining traction all over the U.S. “With the longstanding experience and close proximity to centers of production, Europe usually tends to lead adoption of new ceramic technology, but North America is quickly gaining ground in consumption of GPTP, partly because of domestic stocking programs at manufacturer or privately-owned distribution centers,” Fasan explained. “Both coasts [East and West] tend to be the early adopters of new products and that was certainly the case with GPTP, however, larger formats are making their way all across the country. As more industry standards, installation guidelines and contractor training programs arise, it makes it much easier for a specifier to get past the barriers to entry.”

“GPTP have been very popular throughout Europe for some time now, which is driving the porcelain slab movement into the U.S.,” said Roy Viana, director of natural stone and slab at Dal-Tile Corp. “Large-format porcelain slabs are now becoming an in-style choice for U.S. consumers. The demand and acceptance of porcelain slabs for walls and countertops is coming from both coasts driven by trends/fashion, flexibility and functionality of the format size.”

“Throughout Europe, GPTP have been trending and very popular for some time now. However, over the past eight years, we have seen a growing demand year after year here in the U.S. market,” Fanisi added. “We have seen a great amount of success on both the East Coast and West Coast, with a greater demand now picking up in the Midwest and southern states as well.”

GPTP Applications

The most common places that GPTP are used are on indoor walls and floors, as well as countertop. As of late, exterior cladding is also becoming a popular design feature. “Extra-large porcelain slabs are being used for countertops, walls and floors -- in that order,” Viana said. “Porcelain countertops are the hot trend. The large porcelain slab-size format offers installation flexibility in unlimited colors and patterns. Larger slabs mean fewer seams/grout joints to break up the run of the countertop or wall. In turn, this speeds up installation, reduces the potential for seam issues and ultimately reduces cost.

“Thin slabs are an option in porcelain offering versatility because the slabs are so thin and lightweight,” he went on to say. “Thin porcelain slabs work well as backsplashes and other wall panels, panels for the sides of cabinetry or kitchen islands, and as decorative accents throughout the home. No sealing is needed and cleanup is easy. Unlike natural stone that needs to be sealed after installation and resealed every few years to prevent several potential problems, porcelain does not ever have to be sealed.”

“Another growing application is for ventilated facades/rainscreen cladding systems or even direct bond application on exterior walls,” Panisi added. “The more recent introduction of 12- and 20-mm-thick slabs has opened new opportunities for countertop, tabletop and worktop applications.”

Thanks to the variety of thicknesses, GPTP can be used for a wide variety of applications. “Countertops and furniture worktops are the fastest growing categories now that 12- and 20-mm gauges are readily available,” Fasan said. “For a long time, GPTP was only available in slimmer gauges (3.7 to 6 mm), but with the advent of thicker formats that can operate as worktops without a structural substrate, the material is quickly gaining market share due to its unmatched performance combined with almost limitless aesthetic options.”

Although more commonly used throughout Europe, GPTP have been making strides throughout the U.S. In addition to being implemented indoors, there has also been a rise in exterior use as cladding for residential and commercial spaces. Photos courtesy of Florim and Laminam, respectively

The Benefits of GPTP

Compared to other flooring materials such as natural stone, wood and LVT, GPTP stands out because of their low maintenance. “The main benefits of GPTP are aesthetics, durability and low maintenance,” Panisi said. “It is also possible to control the look to match the design intent. This material is extremely durable in not only residential projects, but also in heavy commercial spaces with a large amount of foot traffic. The material’s resistance to staining and scratching also makes it very easy to clean and maintain.”

“Porcelain stoneware surfaces and coverings combine aesthetics with high-performance standards thanks to the material’s inherent features: ease of cleaning and maintenance, resistance, fire- and waterproof nature, frost resistance, and last but not least, the health and ‘green’ advantages (no release of VOCs or harmful substances, pre- and post-consumer recycled content, etc.),” added the Style & Design Center at Atlas Concorde.

Mazzetta and Viana piggybacked Panisi's comments, adding how GPTP is a cheaper alternative to other types of flooring materials. 

“The overarching benefits of extra-large porcelain slabs are their ‘endless design possibilities,’ as well as the fact that they are a great solution for designs that require a high-end look, but are limited by budget or performance constraints,” Viana said. “Extra-large porcelain slabs easily bring the scale and style of natural stone slabs to projects where stone might be cost or installation prohibitive. Another benefit of using extra-large porcelain slabs is the ability to ‘create style and luxury through seamless, continuous design,’ which is currently one of the hottest trends in interior design.”

Fasan agreed with Mazzetta and Viana, highlighting all of the benefits of GPTP. “All the inherent benefits of high-density ceramics like zero VOCs as a primary (in and of itself) or secondary (as a sink for existing off-gassing chemicals within a space); inert nature that is unaffected by flood, fire or even UV light exposure; high impact and scratch resistance; high resilience to chemicals and acids; high thermal mass and low-conductivity, meaning easy integration of smart-home tech and even appliances such as embedding induction cooktops within the slabs -- the list just keeps going on,” he said. “The large scale also takes out a lot of the grout in an installation -- the only place for moisture penetration and dirt or bacteria accumulation within a tile installation. When you add up all of these benefits and realize that the material is likely to outlive your children and you can get it in eye-popping realistic digital reproductions of almost any material you could desire, it’s not surprising that these GPTP formats are gaining traction with consumers and specifiers alike.”

In terms of the future, Fasan doesn’t see GPTP slowing down anytime soon. “The next horizon for this technology, at least for worktops, is full-body decoration so that edges can be worked just like natural stone or quartz agglomerates and the design on the face travels through the edge face. There are already manufacturers making headway in this direction with effects like terrazzo and exposed aggregates being produced in full-body versions. Marble veining is not far away,” he concluded.