Grout starts light and ends up grey within a few years, no matter how often you mop. Dirt, grease, and soap scum work into the porous surface and sit there, making even a freshly cleaned floor look tired. If you’ve been scrubbing on your hands and knees with little to show for it, you’re not doing anything wrong, you just haven’t found the best grout cleaning method for your tiles yet.
This guide walks through the approaches that actually lift ingrained grime, from household staples like bicarb and vinegar to steam cleaning and stronger commercial degreasers. We’ll tell you which methods suit light everyday build-up and which ones you need for grout that hasn’t seen a proper clean in years, so you stop wasting time on techniques that only shift dirt around.
We’ve picked up plenty of this knowledge cleaning tiled floors, bathrooms, and kitchens across homes and businesses from the Central Coast grout cleaning area through to Newcastle. Below you’ll find practical, tested methods ranked by effort and results, plus a clear point where it makes more sense to call in professional tile and grout cleaning rather than keep fighting stains yourself.
1. Book a professional tile and grout clean
Sometimes the fastest route to clean grout is skipping the DIY stage altogether. Years of grime, grease, and soap scum bond to the porous surface of grout in a way that no amount of scrubbing with a toothbrush will fully reverse. A tile and grout cleaning service uses hot water extraction and commercial-grade equipment that pulls dirt out from below the surface, not just off the top.
How it works
Technicians apply a pre-treatment solution that breaks down grease and mineral build-up, then use a high-pressure hot water system with a specialised grout tool to flush the loosened dirt out of the lines. The hot water extraction process reaches temperatures and pressure levels that household mops and DIY pastes simply can’t match. Most jobs also include sealing grout after cleaning, which slows down how quickly the grout re-absorbs dirt and makes your next clean easier.
If your grout hasn’t looked genuinely clean in years, no amount of scrubbing will beat proper hot water extraction.
Best for
This method suits heavily stained or neglected grout, end-of-lease cleans where bond return depends on presentation, and busy households or commercial kitchens where grime builds up faster than anyone has time to manage. It’s also the right call if you’ve already tried bicarb pastes and vinegar with disappointing results, since professional equipment lifts what surface treatments leave behind.
Cost
Pricing depends on the size of the area and how bad the staining is, but tile and grout cleaning costs per m² typically start from around $2.50. Getting a quote is straightforward:
- Request a free quote through the contact form, listing the rooms or areas needing attention.
- Upload a few photos so the quote reflects the actual condition of your tiles.
- Ask about combining the job with carpet or upholstery cleaning if you’re doing a full property refresh.
Things to watch for
Not every provider uses genuine hot water extraction, some rely on surface mopping with stronger chemicals, which doesn’t solve ingrained staining long-term. Confirm the technician will pre-treat, extract, and ideally seal the grout afterwards, and ask how long the job takes so you can plan around wet floors and drying time before foot traffic resumes.
2. Baking soda and hydrogen peroxide paste
Mixing baking soda with hydrogen peroxide gives you one of the most effective DIY options for grout that’s turned grey or yellow. Bicarb provides the gentle abrasive scrubbing action, while the peroxide acts as a mild bleaching agent that breaks down organic stains without the harsh fumes of chlorine bleach.
How it works
Combine three parts baking soda with one part hydrogen peroxide (the standard 3% solution from the chemist works fine) until you get a thick paste. Apply it directly to the grout lines with an old toothbrush, leave it for 10 to 15 minutes, then scrub in small circular motions before rinsing with warm water.
Bicarb and peroxide lift stains that plain water and scrubbing never will, without the harsh smell of bleach.
Best for
This paste suits light to moderate discolouration on white or light-coloured grout, particularly in bathrooms where soap scum and mildew build up. It’s a solid middle step if plain bicarb and water hasn’t cut through the staining but you want to avoid stronger chemicals.
Cost
Expect to spend under $10 total, since both ingredients are pantry or chemist basics you likely already have. A 500g box of bicarb and a bottle of peroxide will cover several rounds of cleaning across a whole bathroom or kitchen floor.
Things to watch for
Hydrogen peroxide can lighten coloured or dark grout if left on too long, so test a small hidden section first. Ventilate the room while you work, and never combine this paste with other cleaning chemicals, particularly anything containing ammonia.
3. Baking soda and water paste
Sometimes the simplest option is the right one. A plain baking soda and water paste is the gentlest DIY approach on this list, and it’s often the first thing worth trying before you reach for stronger chemicals or a professional service. It won’t touch deep mould or years-old grease, but for everyday grime it works surprisingly well.
How it works
Mix baking soda with a small amount of water until it forms a thick, spreadable paste, roughly three parts powder to one part water. Spread it along the grout lines with a spoon or old toothbrush, let it sit for 10 minutes, then scrub with a grout brush using firm, short strokes. Rinse thoroughly with warm water and a clean cloth, since dried bicarb residue can leave a chalky film if you skip this step.
A bicarb and water paste is the safest starting point for grout cleaning, especially on coloured or delicate tiles.
Best for
This method suits light dust, everyday grime, and mild greying rather than deep-set stains or mould. It’s also the safest option for coloured, patterned, or older grout where you’re worried about bleaching agents causing damage.
Cost
Bicarb costs next to nothing, a standard box runs a few dollars and lasts through dozens of cleaning sessions. You won’t need any specialised equipment beyond a brush you probably already own.
Things to watch for
Expect to repeat the process several times on stubborn patches, since plain bicarb has no bleaching or disinfecting power. If discolouration persists after two or three attempts, move on to a stronger method rather than scrubbing harder.
4. Baking soda and vinegar solution
The classic bicarb and vinegar fizz gets recommended everywhere, but it works better as a pre-treatment than a standalone fix. The chemical reaction looks dramatic and helps loosen surface grime, though the fizzing itself doesn’t do much scrubbing for you. Used correctly, though, this combination handles greasy kitchen grout that plain bicarb paste struggles with.
How it works
Sprinkle a generous layer of baking soda directly onto damp grout lines, then spray or pour white vinegar over the top, the same way you would when cleaning tile grout with vinegar and baking soda anywhere else in the house. Let the fizzing settle for two to three minutes, then scrub with a stiff grout brush while the mixture is still active. Rinse well with warm water afterwards, since leftover vinegar residue can dull tile finishes over time.
Bicarb and vinegar work best as a loosening step before scrubbing, not as a magic stain remover on their own.
Best for
This solution suits greasy grout near cooktops and grout with a general film of everyday grime rather than dark mould or set-in stains. It’s a good next step if the plain bicarb and water paste from method three hasn’t cut through kitchen grease.
Cost
White vinegar costs a few dollars a litre and lasts through months of household cleaning, on top of the bicarb you already have. There’s no equipment cost beyond a brush and spray bottle.
Things to watch for
Avoid using this on natural stone tiles, since the acid in vinegar can etch marble, limestone, and travertine surfaces. Never mix vinegar with bleach or bleach-based products, as the combination releases toxic chlorine gas.
5. Commercial grout cleaning products
When bicarb and vinegar haven’t made a dent, a shop-bought option like a Bunnings grout cleaner is the logical next step before you consider anything stronger. These formulas are built specifically for grout, with surfactants and degreasers designed to cut through grease and ground-in dirt that household staples can’t shift on their own.
How it works
Most commercial grout cleaners, including the Selleys grout cleaner, come as a gel or spray you apply directly to the lines, leave for the time stated on the bottle (usually 5 to 10 minutes), then agitate with a stiff brush before rinsing. The active ingredients, typically sodium hypochlorite or specialised degreasing agents, break down grime at a molecular level rather than relying purely on abrasion.
A dedicated grout product does the chemical heavy lifting that scrubbing alone can’t manage.
Best for
These products suit moderate to heavy staining where pantry remedies haven’t worked, and they’re handy for anyone who wants a reliable result without mixing up pastes each time. Renters preparing for an inspection often reach for these first since they’re quick and widely available at the supermarket.
Cost
Expect to pay between $8 and $20 per bottle, depending on the brand and whether it’s a spray, gel, or foam formula. One bottle usually covers a full bathroom or small kitchen floor, though heavily stained grout will chew through product faster.
Things to watch for
Check the label against your tile type first, since some formulas aren’t safe on natural stone or coloured grout. Always ventilate the room, wear gloves, and never mix products from different bottles, as combining bleach-based and ammonia-based cleaners produces dangerous fumes.
6. Oxygen bleach cleaner
Oxygen bleach sits between the mild pantry pastes and harsh chlorine bleach, giving you a strong whitening result without the fumes or the risk to coloured grout. Sold as a powder under various brand names, it’s built around sodium percarbonate, which releases oxygen bubbles once mixed with water and works those bubbles into the porous grout to break stains apart from within.
How it works
Dissolve the oxygen bleach powder in warm water following the ratio on the packet, usually a few tablespoons per litre, then pour or spray it onto the grout lines. Leave it to sit for 15 to 30 minutes so the oxygen reaction can work through the stain, scrub with a stiff brush, then rinse thoroughly.
Oxygen bleach whitens grout without the fumes or colour risk that come with chlorine bleach.
Best for
This method suits medium to heavy discolouration across both white and coloured grout, since it’s far less likely to strip colour than chlorine-based products. It’s also a sensible pick for households with pets or kids around, given the lower fume risk during application.
Cost
A tub of oxygen bleach powder runs roughly $10 to $15 and covers several large cleaning sessions, since you’re only mixing small amounts at a time. That tub will comfortably outlast a full bathroom and kitchen clean with product left over.
Things to watch for
Give the powder time to fully dissolve, since undissolved granules can scratch softer grout surfaces during scrubbing. Wear gloves regardless of the milder reputation, and don’t leave the solution on longer than instructed, as it can dry out and leave a chalky residue that needs a second rinse.
7. Chlorine bleach for mould and stains
Chlorine bleach is the strongest option on this list, and you should treat it as a last resort rather than a first attempt. It kills mould spores and strips out the darkest staining that oxygen bleach and bicarb pastes can’t fully shift, but it’s harsh on skin, lungs, and coloured grout alike.
How it works
Dilute household bleach with water, roughly one part bleach to four parts water, and apply it to the grout lines with a small brush or spray bottle. Leave it for 5 to 10 minutes, never longer, then scrub with a stiff brush and rinse thoroughly with plenty of clean water. The chlorine breaks down mould pigment and disinfects the surface, which is why this method works where colour-safe cleaners fall short.
Chlorine bleach handles black mould in grout better than anything else on this list, but it’s the harshest method here too.
Best for
This method suits removing black mould from bathroom grout, particularly around showers and tubs where damp conditions let spores take hold. It also works on heavily stained white grout where you’ve already tried oxygen bleach without success.
Cost
A standard bottle of household bleach costs around $3 to $6 and lasts through months of occasional use, since you’re diluting it heavily each time. There’s no extra equipment needed beyond gloves and a brush you’d already own.
Things to watch for
Always ventilate the room fully and wear gloves, since bleach fumes irritate eyes and airways quickly in an enclosed bathroom. Never mix bleach with vinegar or ammonia-based products, and avoid using it on coloured grout, as it will lighten or strip the pigment permanently.
8. Steam cleaning
A domestic steam cleaner offers a chemical-free way to lift grime out of grout, using nothing but hot vapour and pressure. It won’t bleach out deep staining the way oxygen or chlorine bleach can, but for households that want to avoid chemicals altogether, it’s a genuinely effective middle-ground method.
How it works
Fill the steam cleaner’s tank with water and let it heat up until it produces a steady jet of high-temperature steam, usually somewhere above 100°C. When cleaning tile grout with a steam cleaner, run the nozzle slowly along the grout lines, holding it in place for a few seconds on stubborn patches, then follow up with a stiff brush to work loose whatever the steam has softened. Wipe away the residue with a microfibre cloth as you go, since steam cleaning leaves grout damp rather than wet.
Steam lifts everyday grime without a drop of chemical cleaner, which suits households wanting a more natural approach.
Best for
This method suits households cleaning shower grout naturally without bleach, families with young kids or pets, and grout with light to moderate build-up rather than dark mould or years-old staining. It also works well as regular maintenance between deeper cleans, keeping grime from setting in permanently.
Cost
A basic grout cleaning machine for home use costs anywhere from $50 for an entry-level model up to $200 or more for a unit with attachments built for grout lines. There’s no ongoing product cost beyond tap water, which makes it cheap to run long-term.
Things to watch for
Check your tile adhesive can handle sustained heat and moisture, since some older installations aren’t rated for steam. Ventilate the room afterwards to help grout dry fully, and avoid overloading unsealed grout with repeated steaming sessions, as trapped moisture can encourage mould rather than prevent it.
Choosing the right method for your tiles
Matching the method to the mess saves you time and protects your grout from unnecessary damage. Light dust and everyday grime respond well to a bicarb paste, greasy kitchen lines need the vinegar reaction, and stubborn discolouration calls for oxygen or chlorine bleach depending on your grout colour. Steam suits households wanting a chemical-free routine, while commercial products fill the gap when pantry staples fall short.
Grout that’s stayed grey through several of these methods has usually gone past what DIY can fix. Years of build-up sit deep in the porous surface, and no amount of scrubbing recovers what hot water extraction pulls out properly. That’s the point where it makes sense to stop testing pastes and book a professional clean instead, particularly if you’re chasing bond return or just want your floors looking new again without the weekend spent on your knees. If that’s where you’ve landed, see what a professional tile and grout cleaning service costs and get in touch with SMK Carpet Cleaning for a free quote.