Tile Grout Types and Sizes: A Homeowner's Guide

Grout is the material that fills the joints between tiles after they are set. Grout type refers to the composition of the grout material sanded, unsanded, or epoxy and determines its durability, flexibility, stain resistance, and appropriate applications. Grout joint size refers to the width of the gap between tiles, which affects the finished look of the tile installation as much as the tile itself.

At Phoenix Home Remodeling, grout selection is part of every tile specification conversation. It is one of the most overlooked decisions in a kitchen or bathroom remodel and one that homeowners frequently wish they had thought through more carefully after the fact.

Because grout covers a significant portion of the visible tile surface area and has a major impact on both aesthetics and maintenance. A narrow grout joint in a matching color makes tile look almost seamless. A wide grout joint in a contrasting color makes the individual tile shape the dominant visual element. The wrong grout type in a wet area fails prematurely, cracks, stains, and becomes a maintenance problem that is expensive to fix without retiling.

• Sanded grout: Contains fine sand aggregate that provides bulk and strength. Required for joints wider than 1/8 inch. The most commonly used grout type for floor tile and most wall tile applications. Available in a wide range of colors. Requires sealing to resist staining in kitchen and bathroom applications.
• Unsanded grout: A smoother, finer grout without sand aggregate. Used for joints 1/8 inch or narrower. Also used with delicate tile surfaces like polished marble or glass where sanded grout could scratch the tile face. Requires sealing.
• Epoxy grout: A two-part grout made from epoxy resin rather than cement. Highly stain resistant, does not require sealing, and is significantly more durable than cement-based grout. More expensive and more difficult to install, it sets quickly and is harder to clean off tile surfaces during installation. Best for kitchen countertop backsplash areas and commercial applications where stain resistance is a priority.
• Urethane grout: A pre-mixed grout that is easier to work with than epoxy but offers better stain resistance than standard cement grout. A middle-ground option that is becoming more popular in residential remodeling.

Cement-based grout, both sanded and unsanded, is porous and should be sealed in kitchen and bathroom applications to resist staining and moisture penetration. Epoxy and urethane grouts do not require sealing. Sealing should be done after the grout has fully cured, typically 72 hours after installation, and reapplied every one to three years depending on the product and the application.

In some cases, yes. Grout colorants and stains can be applied over existing cement-based grout to change or refresh the color. This works best when going from a lighter to a darker color. Going significantly lighter is very difficult. If the grout is cracked, crumbling, or deeply stained throughout, replacement is a better option than colorant application.

• What grout type do you recommend for this tile in this application?
• What joint width are you planning to use and how does that affect the finished look?
• Should I use epoxy grout in the backsplash area behind the stove?
• How soon after installation should I seal the grout and what product do you recommend?

See also: Subway Tile, Walk-In Shower Design, Bathroom Remodel Budget, Kitchen Remodel Cost Breakdown, ADA Bathroom Requirements