Choosing the Right Grout – Cement vs. Epoxy

There is no denying the enduring popularity of tile and stone as covering options for floors and walls. While advances in kiln technology in recent decades have expanded the options for large-format ceramic tiles, no matter what size or shape they are, they all have grout lines that need to be filled, and that means making the choice between a cement or epoxy grout.

Of course not all grouts are the same – while color options are an important consideration, so is the durability and ease of maintenance of any installation. Professional installers know that making the right grout choice can be a huge factor in whether those gorgeous stones or tiles remain looking good for decades – or become beset with issues.

No one wants to be endlessly dealing with stain and efflorescence build-up; and a poor choice in grout could take years off the lifespan of an otherwise solid and beautiful installation. So what are the different options and how does one choose between them?

Grouts for tile and stone can be separately into two basic categories: Cement-based grouts and epoxy grouts. Choosing between cement grout and epoxy grout depends on your specific needs, budget, and the application. Here's a comparison of the two basic options:

Cement Grout

Composition and Properties:

• Traditionally made from a mixture of Portland cement, water, and sometimes sand
• Porous material that can absorb water and stains
• Requires regular sealing to maintain water resistance

Advantages:

• Economical and easy to use, requiring only water for mixing in most cases
• Easy to work with, especially for DIY projects
• Generally allows for more flexibility in tile movement
• Available in a wide range of colors

 Disadvantages:

• Less durable and prone to cracking over time
• Requires regular maintenance and resealing
• More susceptible to staining, discoloration and efflorescence

For installations where those conditions aren’t a concern, such as residential interior spaces not subject to excessive dampness or staining, MAPEI has Keracolor^® U (unsanded) and Keracolor S (sanded) Portland-cement-based grouts available in available in 13 colors – and at reduced upfront cost. The choice between the two is based solely on the width of the grout lines: use sanded Kereacolor S when working with grout joints of between 1/8" and 5/8" [3 to 16 mm) and unsanded Keracolor U for 1/16" to 1/8" (1.5 to 3 mm) grout joints. They both also contain BioBlock® technology for mold and mildew resistance. In addition, the use of a sealer, such as those offered by MAPEI within the UltraCare^® line, can mitigate those issues inherent to all Portland cement grouts.

But what if the added time and cost of using a sealer isn’t something you bargained for? MAPEI innovation came into play to develop another option: the high-performance Ultracolor^® Plus FA, a rapid-setting, “All-in-One” grout replacement for sanded and unsanded grouts.

By incorporating MAPEI’s High-Hydrated Cement Technology, there is no resultant efflorescence, nor color inconsistency. Along with offering higher polymer content, HCT reduces absorption and increases stain resistance when compared with standard-performance cement grouts. It also has DropEffect^™ technology, which reduces surface absorption, helping to repel water, dirt and grime from penetrating grout joints. Essentially, any water-based spills on the cured grout bead up. And the quick-drying aspect makes it great for projects needing quick turnaround times. Ultracolor Plus FA is also a part of the MAPEI Zero line of products fully offset for CO₂ emissions measured throughout their entire life cycle.

Epoxy Grout

Composition and Properties:

• Two-component (epoxy resin needing to be mixed with a hardener)
• Non-porous and highly resistant to water and stains
• Does not usually require sealing

Advantages:

• Extremely durable and long-lasting
• Well-suited for commercial and industrial projects
• Highly resistant to stains, chemicals, and harsh weather conditions
• Ideal for high-traffic areas and moisture-prone spaces like showers
• Available in a wide range of colors

Disadvantages:

• Often the more expensive option on the store shelf
• Usually very quick-setting, making it challenging for DIY projects and amateur installers to work with
• May be less flexible than cement grout

Option 3: Ready-to-Use Grout

Ready-to-use grout acts like an epoxy but it’s not an epoxy exactly. It’s not as robust as Kerapoxy^® IEG CQ for commercial kitchens, but for residential installations, if someone wants the benefits of an epoxy grout but they want something easy to work with and ready-to-use, it is a great alternative. One such grout is MAPEI Flexcolor^® CQ, a professional-grade, ready-to-use specialty grout for precision commercial and residential installations with porcelain, ceramic and natural-stone tiles. It can be used to grout interior/exterior tile, and its dense composition helps to prevent water-based stains by providing water repellency to the grout surface. MAPEI Flexcolor CQ is formulated with the latest innovation in quartz aggregate, which ensures color consistency, ease of cleanability and improved workability. In addition, this grout can be used on sensitive tile surfaces once tested, requires no sealer and cures naturally from evaporation of the low level of water in the formulation.

It doesn’t contribute to efflorescence and is stain and chemical-resistant with no sealing required. It can be used for joint sizes 1/16" to 1/2" (1.5 to 12 mm). It should not be used for water submersion installations such as pools or for use with pebble-stone or river-rock tile or mosaics. If someone is looking for an easy and fast installation, this is the fastest grout to lay down. It’s ready to use straight from the pail with no mixing required.

Comparison testing of MAPEI Flexcolor CQ versus traditional Portland-cement grout has verified that MAPEI Flexcolor CQ is 30% more cost-efficient (based on typical rates of installers) and requires 65% less time to install.

Choosing the Right Grout

Floor Tiles:

Epoxy grout is ideal for high-traffic areas due to its durability and resistance to cracking. However, cement grout may be sufficient for low-traffic areas if properly sealed and maintained.

Bathrooms and Showers:

While Ultracolor Plus FA is good for most residential and commercial wet and submerged areas, an epoxy grout, such as Kerapoxy CQ, is an even better choice, due to its superior water resistance and durability. It provides stain- and chemical-resistance and is water-cleanable and easy to maintain.

Kitchen Backsplashes:

Epoxy grout is superior in factors like stain resistance and ease of maintenance, especially in areas exposed to food splatters and grease. For commercial kitchens, MAPEI developed an industrial-grade epoxy grout: Kerapoxy IEG CQ. Like its sister product Kerapoxy CQ, it meets ANSI 118.3 specification, but with even higher resistance to chemicals, stains and very high temperatures, allowing the use of steam-cleaning and no-rinse cleaners.

Outdoor Applications:

Epoxy grout's resistance to harsh weather conditions makes it suitable for outdoor use. However, cement grout can also be used if properly sealed and maintained – especially Ultracolor Plus FA.

While epoxy grout is generally more expensive than cement grout, the initial cost can pay off handsomely in the long run for commercial and industrial projects requiring the extra high performance offered, with better overall protection of the tile and adhesive lending a longer lifespan to the installation, as well as lower maintenance requirements generally. For most applications, especially in moisture-prone or high-traffic areas, epoxy grout offers superior performance and durability compared to traditional Portland-cement grout. But as we’ve seen with the ready-to-use MAPEI Flexcolor CQ and the popular Ultracolor Plus FA, some cement grouts are higher performing than others.

For those looking for a deep dive on the technical details, you can learn about the particulars of cement and epoxy grouts from The American National Standards Institute (ANSI). They created a helpful classification system to guide installers based on what standards each product meets. The Tile Council of North America (TCNA) and the Terrazzo, Tile & Marble Association of Canada (TTMAC) also provide guidance for installers.

And smart consumers always look for industry specifications when selecting construction materials. That’s why MAPEI tile & stone installations products always carry both the ANSI and International Standards Organization (ISO) 13007 classifications codes, on both the packaging labels and the Technical Data Sheets (TDSs) found on our Website, www.mapei.com.