DIY Cleaning Recipes That Work, and 3 That Damage Surfaces

Most DIY cleaning advice online is copied from other DIY cleaning advice online, and very little of it has met a real bathroom. Some of it works well and costs almost nothing. Some of it is chemistry theatre. A few of the most-shared mixes will permanently mark a benchtop, and one family of combinations is genuinely dangerous. Here is what I make, in what proportions, what I skip, and where a well-made product beats a jar of bicarb.

What actually makes a cleaner work

There are only 4 mechanisms doing anything in a cleaning product. Surfactants (soap and detergent) lift soil off a surface and hold it in the water so it rinses away. Acids dissolve minerals: limescale, soap scum, the chalky film on a shower screen. Alkalis break down fat and oil. Abrasives and physical effort remove what is stuck on.

Almost every household job is a surfactant plus effort. That is why a fragrance-free clean works: the tools and the technique are doing what harsh chemistry gets credit for. For the longer version of how to judge what is in a bottle, I have written it up in our guide to eco-friendly cleaning products in Australia.

A DIY recipe earns its place when it delivers one of those 4 mechanisms cheaply and reliably. It wastes a Saturday when it does not.

The recipes worth making

Everything below uses ingredients already in the pantry or the laundry cupboard. For the background on each one, what it does and where it fails, bicarb, castile soap and hydrogen peroxide are covered here in detail.

Citric acid solution for mineral build-up and soap scum

Dissolve 1 to 2 tablespoons of citric acid powder in 500ml of warm water. Stir until it runs completely clear, or it will block the spray nozzle. Use it on glass shower screens, taps, tiles, the inside of a kettle and the base of a toilet bowl.

Spray, leave it 5 to 10 minutes, agitate with the right brush, then rinse properly with water. The rinse is not optional. Acid left on a surface keeps working on that surface. Citric acid beats vinegar on the same job, does not fill the house with a smell, and is cheap by the kilo. Keep it off marble, limestone, travertine, natural stone and unsealed grout, for the reasons below.

Bicarb paste for baked-on grime

Mix 3 parts bicarb soda to 1 part water. You want a spreadable paste, not a slurry. It is good on a stainless sink, an oven floor, a cooktop, and the burnt base of a pan. On heavy baked-on food, leave the paste sitting for 15 to 20 minutes before you scrub, then rinse well.

Bicarb is a fine abrasive with a mild alkalinity, which is a genuinely useful combination against grease. Being abrasive cuts both ways. Test it first on high-gloss acrylic, brushed finishes, painted surfaces and soft aluminium, all of which mark. Where a surface can take a harder abrasive, steel wool does more in less time, and we use it often.

Diluted castile soap for floors and general surfaces

Use 1 to 2 teaspoons of liquid castile soap per litre of warm water. That is much weaker than most people pour, and it is deliberate. Excess soap leaves a film, a soap film attracts dust, and the floor then looks dull faster and gets cleaned more often.

This is the everyday mix for sealed floors, benchtops, doors and door frames. Never add an acid to it.

Hydrogen peroxide, used properly

Hydrogen peroxide at 3 percent, straight from the pharmacy bottle, has real antimicrobial action on hard, non-porous surfaces. It comes with conditions. The surface has to be physically clean first, because soil shields microbes. The peroxide has to stay visibly wet for several minutes rather than being sprayed and immediately wiped. It degrades in light, so leave it in its opaque bottle and do not decant it into a clear spray bottle where it will quietly turn into water.

It will also lighten fabrics, coloured grout and some timber finishes, so test first. Do not add it to anything. This is the one pantry item where the word disinfectant is honestly earned, and the difference between cleaning and disinfecting is worth understanding before you decide you need either, which is why I wrote a separate piece on whether natural cleaners disinfect.

Warm water and a clean microfibre cloth

Unglamorous, and the honest answer for most surfaces in a home that gets cleaned regularly. Fold the cloth in quarters, which gives you 8 clean faces, and turn to a fresh face the moment the one you are using stops being clean. Keep a separate cloth for the bathroom. Most of what people credit to a product is the cloth and the hand behind it.

3 recipes that damage surfaces or do nothing

Vinegar on natural stone, marble and unsealed grout

Acetic acid dissolves calcium carbonate. Marble, limestone and travertine are calcium carbonate. What you get is etching: a dull, slightly rough patch where the polished surface has been eaten away. It is not a stain sitting on top, so no amount of scrubbing brings it back. Restoring an etched stone benchtop is a re-polishing job for a stone specialist.

Unsealed cement-based grout has the same problem more slowly. Repeated acid attacks the binder, and the grout turns chalky and porous. Porous grout holds moisture, and moisture is what mould needs. You end up creating the exact condition you were cleaning against. Vinegar earns its place on some jobs and not others, which I have set out in full in this honest look at vinegar as a cleaner.

Vinegar plus castile soap

This appears in an enormous number of recipe lists, and it should not. Castile soap is a potassium salt of a fatty acid. Add an acid and you convert it straight back into free fatty acids, which is the white curdled mess floating in the bottle. You have unmade the soap and spent the acid at the same time. Neither ingredient survives to do its job.

If a job needs both, use them one after the other, with a water rinse in between.

Bicarb plus vinegar

The fizz is carbon dioxide leaving the mixture. What stays behind is sodium acetate dissolved in water, which is a mild salt solution. An alkali and an acid have cancelled each other out in front of an audience.

There is 1 partial exception, and it is worth naming. Poured down a sluggish drain, the fizz has a small mechanical loosening effect on soft build-up. It is real, and it is minor. A kettle of very hot water and a drain snake will do considerably more, and cost you nothing extra.

The combinations that are never safe

The broader rule is simpler: do not mix cleaning products at all. Not 2 shop-bought products in the hope of something stronger, not a leftover splash of one into the bottle of another. Never decant a product into an unlabelled bottle, and never top up a spray bottle that previously held something else, because the next person to pick it up has no way of knowing what is in it.

We do not use bleach at all. On a porous surface it removes the colour of mould while leaving the growth in place, and it adds moisture to a surface that already had a moisture problem. It looks like a result for about a fortnight.

Why I leave essential oils out

Almost every DIY recipe list ends with the same instruction: add 20 drops of tea tree, or lavender, or lemon. I leave them out entirely, in my own home and in every home we clean.

An essential oil is a fragrance. Plant-derived is not the same as inert, and fragrance is one of the most common triggers in a home, which is exactly why people ask for a fragrance-free clean. At the concentration a homemade spray delivers, the oil is not doing meaningful antimicrobial work either. It is doing scent. A home that smells like something after a clean smells like a residue, not an absence.

When DIY is the wrong call

Bicarb, citric acid and castile soap are cheap. The rest of it is not free. Weigh the following before you commit to mixing your own for everything.

• Shelf life. A water-based homemade mix has no preservative in it. Bacteria and mould will grow in a spray bottle that sits under the sink for a month. Make small batches, write the date on the bottle, and tip out what you have not used within a week or 2.
• Consistency. A well-formulated fragrance-free product is pH-balanced, correctly dosed and tested against common surfaces. A kitchen mix is none of those things, which is why the surface tests above matter.
• Time. Sourcing, mixing, labelling and remaking is a task in itself. For a working household it is often the most expensive ingredient.
• Coverage. Some jobs genuinely need a proper detergent. A greasy rangehood filter is one of them.

My honest position: for most households, a good fragrance-free product plus good technique beats mixing your own. DIY earns its place on the 3 jobs above and little else: mineral build-up, baked-on grime, and everyday surfaces. Past that you are doing unpaid product development.

What we carry, and why

Our kit is deliberately short. Professional HEPA vacuums, the right brush for each surface, steel wool where a surface can take it, citric acid for mineral build-up and soap scum, and physical effort. Every product we use is fragrance-free, with no synthetic fragrance or parfum, no hormone-disrupting chemicals, no SLS, parabens or phthalates, no antibacterial agents including triclosan, no bleach, no dyes or added colours, and no essential oils.

A commodity clean is priced on speed, so harsh chemistry has to compensate for the minutes nobody paid for. We price the time instead, at $85 per hour, which is what lets the tools and the technique do the work. If that is the standard you want in your own home, it is what our natural house cleaning service is built around.

If you take one thing from this: the recipe matters far less than what you do with it. A correct dilution, enough dwell time, the right brush and a proper rinse will outperform any clever mixture applied in a hurry.