Grout starts white and ends up grey, and no amount of mopping fixes it once dirt has worked into those porous lines. If you’re cleaning grout on tiles yourself before reaching for a professional, you need methods that actually shift the grime rather than just move it around the tile.
The good news is that most household grout problems respond well to the right DIY approach. Knowing how to clean tile and grout properly comes down to using the correct mix of ingredients, giving them time to work, and scrubbing with the right tool rather than brute force. Baking soda, vinegar, and a stiff brush handle the majority of everyday staining without any harsh chemicals.
In this guide, we’ll walk through several homemade grout cleaning solutions, explain which stains need which approach, and cover the scrubbing techniques that get into every groove. We’ll also flag when grout has gone beyond a weekend fix, because as a Central Coast and Newcastle cleaning business, we see plenty of tiles that DIY methods simply can’t save.
What you’ll need before you start
Gathering everything upfront saves you walking back and forth to the laundry cupboard halfway through scrubbing a bathroom floor. Cleaning grout on tiles properly means having both the right tools and the right ingredients on hand before you wet a single tile, because half-mixed solutions dry out or lose their punch while you hunt for a spare toothbrush.
Tools that actually reach the grout lines
A mop won’t touch grime sitting in a recessed line, so you need something narrower and stiffer.
- Stiff-bristled brush or an old toothbrush for narrow lines
- Grout brush with an angled head, if you’re doing a full floor
- Spray bottle for even application of your solution
- Old towels or microfibre cloths for rinsing and drying
- Rubber gloves to protect your hands from vinegar and bicarb mixes
- Soft-bristled brush for glazed or polished tiles, so you don’t scratch the surface
Ingredients for your homemade grout cleaning solutions
Most homemade grout cleaning solutions rely on ingredients already sitting in your pantry.
| Ingredient | Best for | Notes |
|---|---|---|
| Bicarbonate of soda | General grime, everyday build-up | Mixes to a paste with water |
| White vinegar | Mineral deposits, soap scum | Never use on natural stone |
| Hydrogen peroxide | Mould and mildew stains | Test on a hidden patch first |
| Oxygen bleach | Stubborn, set-in stains | Follow packet dilution rates |
Match the ingredient to the stain first, and the scrubbing becomes far easier.
Check your grout sealant and tile type before mixing anything acidic, since marble, limestone and travertine react badly to vinegar and will etch or dull permanently. If you’re unsure what you’re dealing with, the Australian government’s consumer product safety resources at productsafety.gov.au outline safe handling for common household cleaning chemicals.
Step 1. Prepare the tiles and grout
Sweep or vacuum the floor thoroughly before you introduce any liquid, because loose grit turns into a gritty paste the moment it meets water and just scratches the tile surface as you scrub. Dry preparation matters more than most people realise when they’re cleaning grout on tiles, since even a fine layer of dust can block your cleaning solution from actually penetrating the porous grout lines.
Follow this before you mix anything:
- Sweep or vacuum the entire area, paying attention to corners and skirting edges.
- Mop with plain warm water to lift surface grime.
- Let the floor dry fully, or wipe it down with a towel.
- Check for cracked or missing grout that needs patching first.
A clean, dry surface lets your solution work on the grout, not the dust sitting on top of it.
Grab a torch and get down at floor level to spot any hairline cracks, since damaged grout will soak up your cleaning mixture and never fully dry, leaving a damp patch that attracts mould again within weeks. Patching those gaps with a matching grout filler before you clean saves you repeating the whole job next month. Once the surface is dust-free and dry, you’re ready to mix your solution and get it onto the lines while it’s still at full strength.
Step 2. Mix and apply a grout cleaning solution
Once your tiles are dry and dust-free, mix your chosen solution fresh rather than pulling out something left over from last month, since bicarbonate of soda pastes lose their fizz and vinegar solutions go flat once opened for a while. Mixing fresh each time gives you the strongest reaction against grime, and it costs you nothing extra beyond two minutes at the sink.
For everyday grime, combine three parts bicarbonate of soda with one part water until you get a thick paste, then work it directly into the grout lines with an old toothbrush. For mould and mildew, skip the paste and reach for hydrogen peroxide straight from the bottle, sprayed on and left to sit. For mineral deposits and soap scum, spray neat white vinegar along the lines, but never on natural stone tiles.
The right mixture matters less than giving it time to actually work before you scrub.
Leave your grout cleaning solution sitting for 10 to 15 minutes so it has time to break down the grime rather than sitting on the surface. Don’t let it dry out completely, especially in warmer rooms or under direct sun through a window, as a dried paste turns to dust and stops working altogether.
Step 3. Scrub away dirt, stains and mould
Now comes the actual scrubbing, and this is where patience beats pressure every time. Scrubbing technique matters more than muscle, so work your brush in short, firm strokes along the length of each grout line rather than side to side, which just spreads the loosened grime across clean tile.
Getting the angle right
Hold the brush at roughly 45 degrees and push the bristles down into the recess, not just across the surface. This gets the stiff bristles right into the porous texture where stubborn stains actually hide.
- Work in sections of one square metre at a time
- Rinse your brush in a bucket of clean water every few strokes
- Reapply paste to any line that’s dried out mid-scrub
Scrub along the grout line, not across it, and you’ll shift far more grime with far less effort.
Dealing with mould separately
Mould needs a different touch. Let the hydrogen peroxide sit its full time before you scrub, then use a soft-bristled brush in circular motions to lift the black spots without spreading spores into nearby lines. Wipe your brush on a paper towel between passes so you’re not just smearing mould residue further along the floor.
Step 4. Rinse, dry and seal the grout
Once you’ve scrubbed every line, rinse thoroughly with clean water, changing the bucket at least once so you’re not just spreading dirty water back into the grout. Rinsing properly matters just as much as the scrubbing itself, since leftover bicarb or vinegar residue attracts dust and grime faster than untreated grout, undoing all that work within a fortnight.
Mop the floor with plain water two or three times, then check the lines closely for any white or grey film left behind. Dry the tiles with old towels rather than leaving them to air dry, because trapped moisture in the grout is exactly what invites mould back in.
Grout that dries fully and gets sealed properly stays cleaner for months, not days.
Why sealing finishes the job
Once the grout is completely dry, usually after 24 hours, apply a penetrating grout sealer with a small foam brush or applicator bottle, following the product’s coverage rate on the label. Sealing the grout closes up those porous lines so future spills sit on the surface instead of soaking straight in, and it makes your next clean far quicker. Skip this step and you’re back to square one within a few months, no matter how thorough your scrubbing was this time round.
Keeping your grout looking fresh
Grout doesn’t need a weekly overhaul once you’ve done the job properly. A quick wipe with a damp microfibre cloth after showers or spills, plus a light bicarb scrub every month or so, keeps grime from building back up in those porous lines. Regular upkeep beats letting stains set in again, and it takes minutes rather than an entire weekend.
But some tiles hold onto years of grime, cracked grout, or mould that’s worked too deep for any homemade mix to shift. When cleaning grout on tiles yourself stops making a dent, that’s your sign the job needs proper equipment and steam that reaches further than a toothbrush ever will.
If your floors, carpets or upholstery need more than a DIY fix, get in touch with SMK Carpet Cleaning for a free quote. We cover the Central Coast to Newcastle, and we’ll get your tiles looking new again without the guesswork.