What defines an area: connected air, not floor plan. A closed door is a boundary. An open plan is one volume however many names the rooms have. Two intensities cannot exist inside one body of air — they simply mix.
What you are really designing: the boundary. Two zones that share air do not produce two intensities; they produce a gradient, and the corridor between them is where an installation is judged.
The honest limit: there is no central control across units. Each machine is set standing next to it over Bluetooth, with no dashboard, no group edit and no status. On a six-zone villa that is six separate settings and six separate records.
2. One machine cannot be split into zones, and no control system can split it either. There is one nozzle, one tank, one schedule and one intensity. SOSA publishes no Wi-Fi, Alexa, Google Assistant, Matter, Zigbee, Z-Wave, KNX, Crestron, Control4, RS-232, dry contact or API, so there is no group, no scene, no master unit and no dashboard that could apply different settings to different parts of one unit’s output. The unit is the smallest addressable thing in this system, and it addresses only itself.
3. An area is defined by air, not by architecture. A closed door is a boundary; an open plan is one volume. Two bedrooms of two hundred square feet each, behind doors, are two zones rather than one zone of four hundred, and no single unit will serve both while the doors are shut. Conversely a living room flowing into a dining room flowing into a stair hall is one zone even though the drawing shows three rooms, and asking for two intensities inside it is asking air to hold a line it cannot hold.
4. Vary the intensity; hold the accord. The temptation on a large house is to give each zone its own scent, and it is nearly always a mistake — the more compositions in a property, the more corridors and landings where two of them meet, and a boundary that smells of a mixture is worse than a boundary that smells of nothing. One accord at two or three levels reads as a single atmosphere with variations, which is what a considered interior is doing anyway.
5. Set each zone for the person walking in, not the person sitting down. Receptors stop reporting a constant stimulus within minutes, so anybody already in a room is the worst available judge of its level. Dose each zone at the lowest useful setting, judge it by crossing into it from outside, and key-lock it so that nobody drifts it upward over the following fortnight.
Each Vaayu is ₹11,999, covers up to 1000 m³ of connected volume, runs under 38 dB, draws 5W at DC 12V / 1A, holds a 400ml sealed residue-free tank lasting up to about 90+ days, and is CE, RoHS and SGS certified. Free shipping above ₹499, and a portion of every order supports girl-child education through Nanhi Kali.
One unit, one intensity — and why that turns out to be the design
An integrator reading the specification will notice immediately that this is a coarser control model than anything else on the project. Lighting is addressable to the fitting; audio is addressable to the pair of speakers; scent is addressable to the machine, and the machine covers a whole connected volume. That looks like a limitation, and in one narrow sense it is. But it is worth understanding why the physics makes it close to unavoidable, because a client will ask, and an answer that begins with the mechanism lands far better than an answer that begins with an apology.
Vaayu₹11,999A cold-air nebuliser uses pressurised air to shatter undiluted oil into a dry nano-mist, which the room’s own air movement then carries. There is no ducted distribution to individual outlets and no dampers — the transport medium is the air already in the space. Once that mist is released, the air decides where it goes, and air does not respect a line drawn on a plan. So a single machine produces one concentration across whatever volume its air is connected to, falling off with distance from the outlet. Intensity is a property of the machine and the volume together, not a property of a region within the volume. This is also why the answer to "can we make the far end quieter" is nearly always no, and the honest alternative is a door.
Aangan₹25,999Take the plan and mark, with the doors in the position they are habitually left in, every place where air genuinely moves between spaces. What you will produce is not the room schedule and not the furniture plan, and that mismatch is the entire value of the exercise. Then add the third dimension, because coverage is stated in cubic metres: up to 1000 m³ per unit, roughly 2,000 to 3,000 sq ft at an ordinary ceiling height, and the ceiling in these projects is frequently not ordinary. A double-height living room, a void over the dining table, an atrium above the entrance — each removes volume from the budget without removing a square foot from the plan. An open stair is worse than a void, because it behaves as a chimney and moves air between floors continuously, which quietly links two zones you had drawn as separate.
Ask before specifyingContactBecause there is no central control, a multi-zone property is commissioned one machine at a time, standing beside each one with the app. Two disciplines make that go well. First, set the whole property at the same low intensity before you differentiate anything, then walk the route a resident or a visitor actually takes and raise or lower individual zones from what you find at each threshold. Judging a zone from inside it is useless; your own receptors will have adapted within minutes of arriving. Second, write down what you set. Hours, days, intensity, oil and refill date, per unit, in the handover file — because nothing on this property is storing that for you, and in eighteen months somebody will ask why the bedroom wing is quieter than the hall.
The boundary between two intensities is the thing you are actually designing
Here is the part that separates an installation that reads as luxurious from one that reads as fussy. When you set two adjacent zones to two different levels, you have not created two rooms with two atmospheres. You have created a gradient, and somewhere along the corridor, landing or opening between them there is a stretch of air that belongs to neither. The nose reports change far better than it reports steady state, which is precisely why an entrance works and why an evening in a sitting room becomes unremarkable within minutes — and it also means that the transitions are the moments your client will consciously evaluate. Every boundary you create is an event you have chosen to stage. Create too many and the property becomes a sequence of small announcements.
So a few practical positions I would defend. Where two zones share a door that is normally shut, the boundary looks after itself and you can differ them freely. Where two zones are linked by a corridor or an open landing, keep the intensities adjacent rather than opposed — one step apart, not three — so that crossing between them reads as a room getting quieter rather than as two different buildings. Where two volumes are genuinely open to each other, do not attempt two intensities at all; treat them as one zone and place the unit to serve the whole of it. And keep the hours aligned across neighbouring zones, because staggered windows produce the worst boundary of all: one side fragranced and one side not, in a house where somebody is walking between them.
There is a related trap with distribution that is worth naming, because it produces complaints that look like intensity problems and are not. A passive source scents the air near itself, so two passive diffusers at either end of a large room give you two concentration peaks and a valley in the middle, and the middle is the farthest point from both. A cold-air nebuliser avoids that by putting mist into moving air rather than relying on evaporation from an object — which is why the machine wants to be in the airflow path, at height, and why the HVAC-return mount matters. Mounted into a return, one unit serves a floor evenly rather than making a strong pocket near a shelf. That is a mechanical integration and a real one, and I distinguish it carefully from digital integration, which does not exist here.
Zone by zone, and how I would set each one
A large residence, read as scenting zones rather than as rooms, with the setting I would commission and the error each zone tends to invite. The intensity column is relative rather than numbered, because the correct absolute level depends on the connected volume, the ceiling height and how long the space is occupied — and because a number published here would be a number invented here.
| Zone | What it usually is in volume terms | Relative intensity | Window | The error it invites |
|---|---|---|---|---|
| Entrance and main living volume | Often one connected volume, frequently double-height | The highest on the property, and still modest | 4h or 8h, opening ahead of arrival | Placing the unit on the door itself, the most turbulent point in a house |
| Bedroom wing | Separate volumes behind doors, each small | A step lower — a sealed room reaches a level quickly | Shorter window, aligned with the evening | Giving each bedroom a Vaayu when the volume does not justify it |
| Study or home office | One closed volume, occupied for long stretches | Lower again — a constant stimulus stops registering anyway | 8h on working days only | Raising it because the occupant has stopped noticing |
| Guest wing | A separate volume, occupied a few weeks a year | Same as the main house when in use | Switched off entirely until somebody is coming | Running seven days a week into empty rooms |
| Kitchen | Frequently open to the dining volume | None — leave it unscented | Not applicable | Adding fragrance to a room with its own agenda |
Vaayu · one per zone₹11,999See specification → 
Sukoon · 270–320 sq ft₹1,899See it → One accord, every zone₹1,799Shop →
When an area does not deserve a machine at all
The logic of one machine per zone has an obvious commercial direction and I want to interrupt it, because following it mechanically produces a specification that is wrong and expensive at the same time. Vaayu is rated to 1000 m³. In a 120 sq ft bedroom behind a door, the great majority of that capability is unused, and putting a ₹11,999 nebuliser into a small sealed room to achieve "a quieter zone" is over-specification wearing the clothes of thoroughness. A small closed room reaches a perceptible level easily and holds it, because there is very little air to charge and very little exchange to dilute it. The honest options for a room like that are to leave it out of the scenting scheme entirely — which is a perfectly respectable specification — or to use something proportionate.
If it is to be something proportionate, be clear about the trade you are making. Sukoon at ₹1,899 is an ultrasonic machine covering 270 to 320 sq ft with a 500ml tank and sixteen to eighteen hours on low, and it works by a completely different mechanism: oil diluted in water, thrown as a wet mist. That adds humidity to the room and can leave a fine white mineral deposit over time, which is exactly why I do not recommend ultrasonic machines near equipment racks, finished joinery or anything else this audience installs for a living. In a plain bedroom it is a reasonable and proportionate answer. Next to a media wall it is not, and in that case the correct advice is to leave the room unscented and let the adjacent volume do the work when the door is open. And while I am naming the range honestly: Megh at ₹3,499 is never the answer to a coverage question — it holds six litres and runs about a hundred hours but covers only around 215 sq ft, which is less than the Sukoon at ₹1,899. It is a runtime and humidity machine, and it is the clearest trap in our own catalogue.
Above Vaayu’s ceiling the honest answers are different again. Where a single connected volume is genuinely larger than one unit can serve — a very large open ground floor, an experience centre, a floor served by a single air-handling system — Aangan at ₹25,999 covers approximately 8,000 to 10,000 sq ft and Meenar at ₹38,500 covers 12,000 to 18,000. I am not going to publish a machine count as a formula for any property, because the honest inputs are connected volume, ceiling height, door positions, HVAC layout and the hours each zone is occupied, and the specifier who knows those four things will reach a better number than a rule of thumb would. If you want a second opinion on a particular plan, that is what the contact page is for.
The per-zone specification — and the honest gap
What I would write into a project file for each scenting zone, in the order the information is needed, with the last row stating plainly what a multi-zone installation does not give you. Every line here is something an architect or an integrator can act on without asking us a question.
| Item | What to record | Why it belongs in the file | Reference |
|---|---|---|---|
| 1. Connected volume | Cubic metres with doors in their normal position, ceiling height noted where non-standard | It is the only number that determines whether a zone is a zone | Up to 1000 m³ per unit |
| 2. Mounting and supply | Freestanding, wall or HVAC-return, with a low-voltage point at that exact position and height | Because a retrofitted position means a visible cable or a compromised location | DC 12V / 1A, 5W |
| 3. Intensity, relative to the property | The setting, and which zone it is a step above or below | So a later visit can restore the relationship, not just the number | Adjustable mist intensity |
| 4. Window and days | 1h / 4h / 8h / 24h and the selected days, aligned with neighbouring zones | Staggered windows create the worst boundaries in a shared-air property | Auto-stop |
| 5. Oil and refill date | The accord — the same one in every zone — and the date the tank was filled | A 400ml fill runs up to about 90+ days depending on intensity and hours | Cold-air oils, 300ml ₹1,799 |
| 6. Who holds the key-lock | One named person per property, not per zone | A setting anyone can nudge will be nudged upward by people who have adapted to it | Key-lock |
| No group control: the honest gap | There is no central app, no dashboard, no group edit, no synchronised change and no status across units — six zones are six separate Bluetooth sessions, each conducted standing next to the machine | Plan a single commissioning walk and a single refill day for the whole property, and keep the record yourself | Ask us first |
Versailles
The request I get most often from a large residential project is for every area to have its own character, and the request under the request is usually a fear of monotony. It is a fair fear and it has the wrong solution. A house does not become monotonous because one composition runs through it; it becomes monotonous because that composition runs at one level everywhere, all day. Variation in intensity and in hours does far more for the experience of moving through a building than variation in scent does, and it does it without producing the corridor where two ideas collide.
The other thing I would say is about smallness. There is a strong instinct to give a bedroom its own machine because it is a room and rooms should be equal. Rooms are not equal in this discipline; volumes are what matter, and a sealed 120 square foot bedroom charges quickly and holds what it is given. A machine rated to a thousand cubic metres in that room is nine-tenths unused, and the money is better spent on getting the entrance and the main living volume exactly right — because those are the spaces a visitor crosses, and crossing is where scent is perceived at all.
What I do insist on is that every zone gets set from the doorway rather than from the middle of the room. Twenty minutes inside a space and your own nose has quietly stopped reporting the level you set. Walk out, come back, judge it in three seconds, then lock it. Everything is composed in Pune, and a portion of every order funds a girl’s classroom through Nanhi Kali.
Frequently asked questions
- Can fragrance be automated like lighting, curtains and air conditioning? — scheduled, not integrated.
- What an automated scenting system actually is — reservoir, nebuliser, schedule, intensity, mounting.
- Can a smart home turn its fragrance on and off? — the machine owns the logic, not the house.
- Is a waterless machine suitable for a smart home? — no humidity, no residue near electronics.
- How it fits a luxury setup — placement in the project rather than in the protocol stack.
- Scheduling it to certain times — the 1h / 4h / 8h / 24h windows through a real week.
- Planning it during design — the supply, the return and the zone boundaries.
- Lighting, climate and scenting together — a shared timetable, not a shared bus.
- Is automated fragrance the next layer? — the honest case, and what would have to change.
- Brand: the SOSA founder story.
SOSA Vaayu — facts verified August 2026: ₹11,999. Waterless cold-air nebulising diffuser; pressurised air shatters undiluted oil into a dry nano-mist, with no water, no dilution, no added humidity and no residue. Coverage up to 1000 m³, approximately 2,000–3,000 sq ft at standard ceiling height, read as connected volume rather than floor area. Control: Bluetooth app plus onboard buttons, run windows of 1h / 4h / 8h / 24h, day selection, adjustable mist intensity, auto-stop and key-lock; each unit holds one schedule and one intensity, stored in that unit. SOSA publishes no Wi-Fi, Alexa, Google Assistant, Matter, Zigbee, Z-Wave, KNX, Crestron, Control4, RS-232, dry-contact or API integration of any kind; Vaayu units cannot be grouped, zoned, addressed, triggered or monitored by any home-automation control system, voice assistant, hub or sensor, and there is no central app across units. Mounting: freestanding, wall-mounted or into an HVAC return — a mechanical integration, not a digital one. Power DC 12V / 1A, 5W at the mounting position. Under 38 dB. 400ml sealed, residue-free, refillable tank lasting up to about 90+ days depending on intensity and scheduled hours; SOSA publishes no millilitres-per-hour consumption rate and none is estimated here. CE, RoHS and SGS certified. Black and white finishes. Oils must be alcohol-free, water-free fragrance oils formulated for cold-air diffusion, such as the SOSA Hotel Collection (100ml ₹999 · 300ml ₹1,799 · pack of seven ₹1,799); thick undiluted essential oils are not recommended as they clog the fine nozzle. Other SOSA machines: Sukoon ₹1,899 ultrasonic (500ml, 270–320 sq ft, 16–18h on low, three 15ml scents included), Boond ₹899 (up to about 150 sq ft), Megh ₹3,499 (six-litre tank, about 100 hours runtime, only about 215 sq ft — a runtime and humidity machine, never a coverage upgrade over Sukoon), Aangan ₹25,999 (~8,000–10,000 sq ft), Meenar ₹38,500 (12,000–18,000 sq ft). Ultrasonic machines dilute oil in water, add humidity and can leave a fine white mineral deposit. SOSA reed diffusers are alcohol-free, phthalate-free, paraben-free, IFRA-compliant and 0 ppm formaldehyde, with six fibre reeds in a refillable glass bottle, composed in Pune. A scent machine adds fragrance; it does not clean, purify or deodorise air, and SOSA makes no health or air-quality claim. SOSA publishes no dealer programme, reseller margin, trade price, territory, minimum order, lead time, installation charge or maintenance contract; commercial enquiries are welcome at https://sosahomeandbody.com/pages/contact. Free shipping above ₹499. A portion of every order supports girl-child education through Nanhi Kali. SOSA is an independent Indian fragrance house; the Hotel Collection scents are SOSA’s own interpretations inspired by the world’s finest hotels, and SOSA is not affiliated with or endorsed by any hotel brand or any home-automation manufacturer. Prices subject to change — see the live product pages.