One third of a cup of regular household bleach per gallon of cool water — five tablespoons — is the dilution the CDC publishes for disinfecting surfaces at home, and you mix it the day you use it. Diluted bleach loses strength as it sits, so last month’s spray bottle under the sink is not a disinfectant any more.
That’s the whole rule. If you’d rather not be the one auditing bottles — we bring our own, eco-friendly by default, and we follow whatever note you leave on your booking. Message us and we’ll send a price for your place.
The ratio, and the bottle it assumes
That number is for plain household bleach — the 5% to 6% sodium hypochlorite kind, the cheapest jug on the shelf. The same guidance publishes it two ways, and the second one is the useful one in a Miami apartment: 5 tablespoons (1/3 cup) per gallon of room-temperature water, or 4 teaspoons per quart. A quart is the batch a small bathroom actually needs, and mixing a quart instead of a gallon is what stops you pouring most of it down the drain when you finish.
Anything sold as concentrated, splash-less, scented or gel is a different product with a different label, and that label — not this article, not the internet — is what governs it. Read the back before you measure. And do measure: a glug from the jug is not a unit. A third of a cup is noticeably less than almost anyone pours by eye, and a cheap measuring cup that lives next to the bucket ends the guessing permanently.
Poured by eye, a bucket comes out stronger than the guidance nearly every time — and stronger is not better. It is just more of everything you did not want: in the air of the room, on the surface, and on your hands.
Why it has to be mixed fresh
A bleach dilution is not something you manufacture once. The published guidance treats a mixed batch as good for the day it was mixed and no longer: the chlorine leaves the solution, and what stays behind is water with a smell. That is the whole reason the instruction says to prepare it fresh. It is not an abundance of caution — it is what the bucket does overnight.
Miami speeds the whole business up. Heat and light are exactly what push chlorine out of a dilution fastest, and the places people store the spray bottle here are a hot utility closet, a garage that bakes by noon, a shelf on a west-facing lanai, or the trunk of a car. Mix what you need, use it, pour the rest out, rinse the bucket. The undiluted jug is the one you are allowed to keep — capped, cool and dark.
And cool water. The CDC wording is room-temperature water and household bleach labels say cool; either way, hot water is the version nobody publishes. It drives more of the chlorine straight into the air of the room you are standing in, so you lose the dilution and keep the fumes.
Three rails that never move
The ratio is the easy part. These three are what actually make a bleach dilution usable inside a house, and none of them bends for a hurry:
- Nothing else goes in the bucket. Not ammonia, not vinegar or any other acid, not rubbing alcohol, not the toilet gel, not a second cleaner of any kind — water is the only thing bleach gets mixed with. Those ingredients hide inside ordinary bottles, which is why the pairs have an article of their own: what you should never mix with bleach.
- Gloves on, air moving. The label prints an irritant warning and an instruction to use it in a well-ventilated area — that is the bottle talking, not us. Gloves, the exhaust fan running before the cap comes off, a door open behind you, and a window cracked somewhere in the house if the weather allows. In a sealed interior condo bathroom the fan is doing all of the work, so leave it running well after you have finished.
- Clean the surface first. Bleach is not a detergent: it will not lift kitchen grease, the soap film on a shower door, or the salt film a coastal window collects — and it cannot disinfect through any of them. Two passes, in that order: one to remove, one to treat, which is the argument laid out in cleaning vs. sanitizing vs. disinfecting.
The third rail is the one that quietly wastes the most bleach in homes here. It comes with a practical consequence, too: contact time only counts while the surface is visibly wet. A pass that flashes dry on a warm counter was a wipe, not a disinfection — and no ratio fixes that.
What this dilution is not for
On porous grout, flat paint or unsealed wood, a bleach dilution takes the color out of a mold stain and leaves whatever was rooted in the material. The grout goes white, the ceiling looks fixed, and in the middle of the wet season it returns in the same outline. That is a plumbing fact more than a biology one: the full mechanism, and the square-footage line the EPA publishes for calling a professional instead, are in vinegar or bleach for mold on walls. White is not the same as solved.
It is also worth reading the surface list your bottle prints before the bucket lands somewhere expensive. Stone counters, unsealed wood, colored textiles and certain metals are the ones that keep coming up in kitchens here — and none of it is guesswork, because the label names them.
And our own boundary, in the words of our terms: “We reserve the right to refuse or stop service where conditions are unsafe for our team — such as mold, infestation, biohazards, or abusive behavior.” A cleaning visit is not a remediation, and no dilution changes that.
Most of the house never needs it
Worth saying plainly, because owning the ratio invites overusing it: the great majority of household cleaning is soap, water, a microfiber cloth and patience. Disinfecting is a separate decision with a short list of moments behind it — the counter that held raw chicken, the bathroom after a stomach bug, the mop bucket for a floor somebody was sick on. Outside that list, bleach is rarely the thing that was missing.
What happens with bleach on a JAS visit
If you hire someone, the useful question is not “do you use bleach?” but “what do you bring, and what happens if I ask you not to use something?” What we publish on our residential cleaning page is this, word for word: “No — we bring everything, eco-friendly products by default and fragrance-free on request. If you’d rather we use a specific product or your own vacuum, leave a note on your booking and we’ll follow it.”
That is a mechanism rather than a vague promise: the booking carries a Special instructions box, the note travels with the job, and the team reads it before they ring the bell. “No bleach indoors” is a sentence you write once and it stays written. That standard visit is, per the same residential cleaning page, a 2–3 hour visit with a 2-person team and 28 items verified by photo, starting at $189.
FAQ
Is a stronger mix better?
No — the published ratio is the ratio. Extra bleach does not buy you a better result; it buys more fumes in a small room, more risk to whatever the bucket lands on, and more residue to rinse off afterwards. When a job feels like it needs a stronger mix, what it usually needed was a cleaning pass first.
Can I keep a spray bottle of diluted bleach under the sink?
Two reasons not to. Within about a day it is no longer the thing you mixed, and a trigger sprayer turns a liquid you could keep away from your face into a mist you walk through. Mix in an open bucket or bowl, in the amount the job actually needs, and pour out what is left when you finish.
Do I have to rinse afterwards?
On anything food touches — counters, cutting boards, the inside of a refrigerator — rinse with plain water and dry the surface, and check your own label, which is where that instruction is printed for your specific product. The drying matters here for a second reason: in this climate a surface left wet behind a closed door is exactly where mildew starts.