How to grout floor tiles
Grouting is the last step that turns a set of laid tiles into a finished floor. This guide walks through it step by step – and shows you how to work out the tiled area and tile count first, so you can judge how much grout to buy.
Work out your tiled area first →
Grout does more than fill the gaps: it locks the tiles together, keeps water out of the joints and sets the final look of the floor. Getting it right is mostly patience and technique. Before you buy, draw your room in the free planner – it gives you the tiled area and tile count from your real floor plan, and the grout calculator turns your tile size and joint into pounds of grout. Then follow the five steps below.
Grouting tiles in 5 steps
Let the adhesive cure, then clean out the joints
Grouting too early lifts the tiles, so wait for the adhesive under them to cure fully – usually 24 hours, longer for large formats or a cold room. Pull out the spacers and rake any adhesive that has squeezed up out of the joints, so nothing sits proud of the tile. Vacuum the dust away so the grout can bond to clean edges.
Choose the grout and color
Match the grout to the joint width: fine joints take an unsanded grout, wider ones a sanded type that resists cracking. Pick the color for the look you want – a tone close to the tile makes the floor read as one surface, a contrasting tone draws the grid. Check the pack is rated for floors, and for wet rooms if the tiles are in a bathroom.
Mix it and work it into the joints
Mix the grout to a firm, lump-free paste and let it slake for the time on the pack. Load a rubber float and spread it diagonally across the joints, pressing firmly so every joint fills solid with no voids. Working across the joints rather than along them is what packs them full and stops the float from dragging the grout back out.
Tool the joints and wash off the haze
Once the grout has firmed up, strike the joints to an even, slightly concave line. Then wash off the haze in stages with a barely damp sponge, rinsing often and wiping in circles – too wet and you wash the grout straight back out of the joints and streak the color. Let the surface mist over between passes.
Polish off and seal the movement joints
When a light film dries on the tiles, polish it off with a dry cloth. Never grout rigid where the floor meets a wall or in the inside corners – those movement joints have to flex, so fill them with silicone instead (sanitary-grade in wet rooms). Keep foot traffic off until the grout and silicone have cured.
Frequently asked questions
- How long after laying the tiles can I grout?
- Wait until the adhesive under the tiles has fully cured, so grouting does not disturb them. With standard cement adhesive that is usually about 24 hours, but large-format tiles, thick beds and cold or humid rooms need longer – go by the adhesive maker's figure rather than the clock.
- What joint width should I choose?
- Joint width depends on the tile: pressed ceramic and small formats take narrow joints of around 1/16–1/8 in, while rectified porcelain and large formats usually run 1/8–3/16 in to absorb size tolerances. Wider joints need a sanded grout. Whatever you pick, keep it consistent – spacers make that easy.
- Do I need to seal the grout?
- Cement grout is porous and picks up dirt and stains, so a grout sealer on floors in kitchens, bathrooms and hallways is worth it once it has cured. Epoxy grout is dense and needs no sealing. Either way, the flexible silicone joints at walls and corners are separate and are not sealed like the grout.
Work out the grout quantity before you shop
Grout coverage depends on the tiled area, the tile size and the joint width. The free planner lays out your real floor plan and gives you the tiled area and the exact tile count; the grout calculator then turns tile size, joint width and joint depth into pounds and bags – no coverage chart needed.
Open the free planner →