How to Apply Non Sanded Grout for Tiles a Step-by-Step Guide

Non sanded grout is a popular choice for glass, polished porcelain, and tight-grout applications where a smooth finish is essential. This guide explains how to apply non sanded grout correctly, from preparation to curing, to achieve durable, clean joints and a professional look. Following these steps helps reduce chipping and ensures a consistent, even appearance across the tiled surface.

Materials And Tools

Assemble the following before starting: non sanded grout in the appropriate color, a grout float with a plastic edge, a clean bucket, a margin trowel, a damp sponge, a grout sealer (if recommended by the manufacturer), a clean microfiber cloth, tile spacers, safety glasses, and gloves. For large jobs, a margin left by a mixing paddle or a drill mixer can ensure uniform consistency. Always check the manufacturer’s instructions for cure time and any specific tools or additives needed.

Surface Preparation

Proper surface prep is essential. Ensure tile faces are clean and dry, with no adhesive residue or dust. Urethane and epoxy grouts require different prep than cementitious non sanded grout, so follow product guidance. If tiles are highly glazed or smooth, a light scuffing with a non-metallic pad can help the grout adhere, but avoid scratching the tile surface. Seal porous substrates before grouting if the tile system or substrate manufacturer recommends it; apply sealer to the grout joints after curing if required.

Mixing The Grout

Follow the manufacturer’s ratios precisely. Use warm water to mix the grout to a peanut butter-like consistency, adding small amounts of water gradually to avoid a runny mixture. Stir thoroughly to remove lumps, then let the mixture rest for 5–10 minutes and remix briefly. The avoid over-watering technique prevents segregation and cracking. Do not mix more grout than you can apply within the pot life stated on the packaging, because non sanded grout sets faster in cooler environments.

Applying The Grout

Load the grout onto the tile surface with the grout float at a 45-degree angle and press firmly to fill joints completely. Work in sections, ensuring all joints are fully closed with no air pockets. Use a light, controlled motion to avoid dragging grout across tile faces. If gaps are wide, apply extra grout and smooth flush along the joint.

Allow the grout to set until a dull film forms on the tile surface, typically 10–15 minutes, then begin cleaning. Do not wait too long; over-drying can cause difficult removal and uneven joints. For corner joints and tight areas, use a damp sponge with a clean water rinse to wipe excess grout from the tile face without pulling grout out of the joints.

Cleaning And Smoothing Joints

Use a clean, slightly damp sponge to remove the excess grout from tile surfaces in a circular motion. Rinse the sponge frequently to prevent pulling grout from joints. After initial cleaning, inspect joints for uniformity. If small voids or rough areas appear, apply a tiny amount of grout with a finger or a small tool and smooth to the same depth as surrounding joints. Allow the grout to cure according to the manufacturer’s guidelines before applying any sealer or water exposure.

Curing And Sealing

Non sanded grout typically cures within 24–72 hours, but full strength may take longer depending on humidity and temperature. Keep the area dry and avoid traffic or heavy use until curing is complete. Many non sanded grouts require sealing to resist stains and moisture; check product instructions for sealer type and application method. Apply sealer after the grout has completely cured, using a clean applicator and allowing it to penetrate and dry as directed by the manufacturer.

Maintenance And Cleaning

To maintain the grout’s appearance, clean spills promptly and use a pH-neutral cleaner suitable for grout. Avoid acidic cleaners, which can erode cement-based grout. For stubborn stains, a grout-specific cleaner or a mild bleach solution may be recommended by the manufacturer, but test in a small area first to prevent discoloration. Regular inspection helps identify worn or cracked joints that may require regrouting or touch-up work.

Common Mistakes And Troubleshooting

Common issues include excess water causing color fading, poor joint fill due to insufficient pressure, and surface haze that requires extra cleaning. If haze remains, use a clean, damp cloth after the grout has cured to wipe the tile surface with minimal pressure. For cracking, re-mix small batches and repair with a dab of grout at the joint depth, followed by careful smoothing. In high-humidity environments, increase curing time and avoid premature cleaning that can pull grout from joints.

Tips For Best Results

• Work in small, manageable sections to maintain consistent curing conditions.
• Keep a clean sponge and water bucket ready to avoid cross-contamination with old grout residue.
• Test a hidden area first if color matching is critical to ensure the grout will blend with tiles and border pieces.
• Wear safety gear and ensure adequate ventilation when mixing powders, especially with cementitious products.
• Follow the manufacturer’s recommended cure times before applying sealers or exposing the surface to moisture.