6 Steps to Grouting Tiles

How do you grout tiles properly?

Grouting is six steps: mix, work it into the joints, let it firm up, clean the tile faces, buff, and wait before it gets wet. The whole job is straightforward, but the timing between steps is what separates a professional-looking result from a patchy one — and the two most common failures, mottled colour and grout haze, both happen in the mixing and cleaning stages rather than in the application.

Tiling can be a costly exercise. With the Selleys White For Life range and a methodical approach, it is well within reach as a DIY job at a fraction of the cost.

What you will need

• Selleys White For Life Powder Grout, with its White For Life Activator
• A measuring cup
• A bucket
• A pointing trowel for mixing
• A grout float or rubber squeegee
• A sponge
• A clean cloth

If you are grouting a small area or doing a repair, Selleys White For Life Ready To Use Grout saves the mixing stage entirely — see the note further down about where it can and cannot be used.

Step 1 — Mix the grout

Add 250 mL of water to the bucket — this is the quantity for mixing 1 kg of powder grout — then slowly add the contents of the White For Life Activator. Now slowly add one bag of powder to the water while mixing. Add no more than an extra 30 mL of water, slowly, while mixing, to obtain a thick consistency.

Allow the mix to stand for approximately 3 minutes, then remix the grout before you start tiling.

Why the water measurement matters more than it looks

The 250 mL plus up to 30 mL tolerance is narrow on purpose. Unequal amounts of water in different batches lead to mottled colouration in the dried grout. That is a whole-wall defect that only becomes visible once everything has dried, and it cannot be fixed without raking the joints out and starting again.

So measure, do not estimate. Use the same measuring cup for every batch, write the quantity down, and resist the temptation to loosen a stiff batch with a splash from the tap. If a batch is genuinely unworkable, mix a fresh one — and note that you must not remix the product once it has started to harden. Grout that has begun to set and is then re-worked will not develop proper strength.

Adding the powder to the water, rather than the water to the powder, is also deliberate: it is what prevents dry lumps forming in the middle of the mix.

Step 2 — Work the grout into the joints

Grout small areas at a time, working the grout into the joints and smoothing off, using a rubber squeegee or a grout float.

Hold the float at an angle and press across the joints diagonally rather than along them — dragging along a joint pulls grout back out of it. The aim is a joint packed solid from the back of the gap to the tile face, with no voids. Voids are where water gets in later.

On a floor, apply a generous amount of grout, and work from the edges so you leave yourself a path to exit. Grouting yourself into a corner is a genuinely common mistake and there is no graceful recovery from it.

Step 3 — Let it firm up

Allow the grout to firm up in the joints — 10 to 15 minutes.

This is the step people skip and it is the reason for most grout haze. Clean too early and the sponge pulls grout out of the joints and smears the slurry across the tile face. Clean too late and the residue has set hard on the glaze. Ten to fifteen minutes is the window where the joint has enough body to stay put and the surface residue is still soft enough to lift.

Step 4 — Clean the tile faces

Using a damp — not wet — sponge, clean the tile surfaces by wiping lightly, in a circular motion. Finish with a single wipe diagonally across the tiles.

Three details matter here. Damp not wet, because excess water washes cement out of the joint and lightens the colour unevenly. Light pressure, because you are lifting residue, not scrubbing. And the final diagonal wipe is what leaves the joint face flat and even rather than scalloped — a circular motion alone tends to dish the joints.

Rinse and wring the sponge frequently. A sponge loaded with slurry just moves the haze around.

Step 5 — Buff after 24 hours

After 24 hours, buff and polish the tile surface with a soft clean cloth.

Through that first 24 hours, prevent spilling any liquids or getting any dirt or contaminants on the grout lines. Fresh grout is porous and takes up whatever lands on it, permanently.

Step 6 — Wait before it gets wet

After the grout has set for an initial 24 hours, leave it for another 3 days before exposing it to water in a shower.

This is the instruction most often compressed, and the consequence is grout that stays chalky, discolours early, or crumbles at the joint edges. Cement-based grout continues to gain strength well past the point where it feels hard. Four days total is the published figure — plan the job around a long weekend rather than around a Sunday evening.

Grout whitens as it dries

Worth knowing so you do not panic mid-job: grout whitens on drying. The joints will look grey and dull while damp and will lighten considerably over the following day. Do not attempt to correct the colour of wet grout — you will only introduce the batch inconsistency that causes mottling.

If you are using Ready To Use Grout instead

Selleys White For Life Ready To Use Grout is a water-based interior grout that removes the mixing and batch-consistency risk entirely, which makes it the sensible choice for small areas and repairs.

Its important limitation: it is not for areas frequently immersed in water, such as shower floors. It can be used on shower walls, and there too the grout must be allowed to dry for 3 days before exposure to water.

For coverage planning, one cartridge covers approximately 2 m² and a 1.4 kg tub approximately 6 m², based on 300 mm × 30 mm tiles with a 5 mm joint depth and 3 mm joint width. Your own coverage will vary with tile size and joint dimensions — smaller tiles and wider joints consume considerably more.

After grouting — sealing and cleaning

New grout is porous. Sealing it is what keeps water, oil-based stains, soil and mould out of it. Selleys White For Life Grout Sealer is sprayed onto clean, dry grout, allowed to penetrate for an hour, then given a second coat, with at least 24 hours before the sealed grout meets water on shower walls, and re-sealing every 12 months. The full method is at how to seal grout.

For ongoing maintenance, Selleys White For Life Tile & Grout Cleaner removes dirt and stains from tiles and grout.

Common questions about grouting tiles

How much water do I add?

250 mL for 1 kg of powder grout, plus the Activator, and no more than an extra 30 mL to reach a thick consistency.

Why did my grout come out patchy?

Almost always because different batches got different amounts of water. Unequal water between batches leads to mottled colouration.

How long do I wait before sponging off?

10 to 15 minutes, until the grout has firmed up in the joints.

Why does my tile face still look cloudy?

Grout haze, from cleaning too late or with too loaded a sponge. Buffing with a soft clean cloth after 24 hours is the step that clears the last of it.

When can I use the shower?

After the initial 24 hour set, leave another 3 days before exposing the grout to water in a shower.

Can I re-mix grout that has started to stiffen?

No. Do not remix the product once it has started to harden.

Where should I start on a floor?

At the edges, working so that you always have a path to exit. Apply a generous amount of grout.

The grout looks grey — did I get the wrong colour?

Wait. Grout whitens on drying.

Can I use ready-to-use grout on a shower floor?

No. White For Life Ready To Use Grout is not for areas frequently immersed in water, including shower floors. It can be used on shower walls.

Do I have to seal the grout?

Sealing helps lock out water and oil-based stains, soil and mould when used as a system. Re-seal every 12 months for ongoing protection.

Do I grout before or after tiling adhesive has set?

After. See how to tile your bathroom — tiles must not be disturbed or subjected to foot traffic for at least 24 hours after laying.