New construction: sealed concrete, gypsum board, laminate, PU and melamine finishes, aluminium windows with gaskets. Very low absorption, very low air leakage, and new materials off-gassing at their peak.
The consequence: old flats need airing and surface work; new flats need ventilation they were designed for but nobody runs.
2. And they have decades of memory. Sixty years of cooking oil aerosol, incense, tobacco, monsoons and floor polish have gone into that plaster and that teak. Sorption works over long timescales: materials absorb slowly and release slowly. On a humid day, when the surface layer of every wall picks up moisture, some of what was absorbed comes back out. This is the one household smell that cleaning genuinely cannot reach, because it is not on the surface — it is in the material.
3. New buildings are sealed rather than absorbent. Cast concrete, cement plaster with acrylic paint, gypsum partitions, vitrified tile, laminate and PU-finished joinery absorb very little. Aluminium or uPVC windows with rubber gaskets, tight door seals and no chimney mean far less accidental air leakage than an old building with timber windows and ventilators. The structure holds no smell — but it also lets nothing out.
4. Which is why a brand-new flat can smell stronger than an old one. Engineered board, adhesives, foam, paints, sealants, carpets, vinyl and new upholstery all release vapour, most heavily in their first weeks and months, and steadily less thereafter. Put that into a flat exchanging only 0.2 to 0.5 of its air an hour and the concentration climbs. The result reads as a slightly sweet, chemical, "new" smell that people describe as stuffy — and it is entirely a ventilation problem with a time limit.
5. So the same complaint has two different fixes. In an old flat you are managing what the building has stored, which means moisture control, air movement and sometimes redecoration. In a new flat you are managing what the contents are emitting, which means running the ventilation the building was designed to have and waiting the materials out. Fragrance is the finish in both cases, never the remedy.
Made in India, composed by an ISIPCA Versailles-trained perfumer — and a portion of every order supports girl-child education through Nanhi Kali.
Why the materials decide the smell
There is a useful way to think about this. Every building is either a sponge or a box. A sponge takes things in, holds them, and lets them back out gradually depending on the weather. A box takes almost nothing in but also lets almost nothing out, so whatever is released inside it stays in the air until something carries it away. Older Indian apartment blocks are sponges: thick masonry, lime or weak cement plaster, timber windows that never sealed properly, stone or mosaic floors, ventilators above every door. Modern towers are boxes: dense concrete, factory finishes, gasketed glazing and no ventilator anywhere. The sponge has a smell of its own. The box has whatever you put in it.
Both of those come with a second-order effect that people mix up with the first. The sponge leaks air, so an old flat has a higher background air-change rate even with the windows shut, which is why old flats rarely feel chemically stuffy — but that leakiness also lets in dust, humidity and the smell of the corridor. The box does not leak, which is why a new flat holds its air-conditioning beautifully and its off-gassing equally well. If you have ever noticed that an old flat smells of the outdoors and a new flat smells of itself, that is the mechanism. Neither is better; they fail in opposite directions, and the fix follows the failure mode rather than the age.
Old, new, and the awkward middle
Step fourFrom ₹749What you are smelling is a mixture of the raw material note — dry lime, old brick dust, seasoned teak, mosaic and floor polish — and decades of absorbed household life. The specific hotspots are built-in wardrobes and lofts, which are almost never emptied and often line an external wall; skirting and door frames in old timber; kitchen walls above the old stove position; and the ceiling above where a lamp or incense once burned. Airing works better on an old flat than on a new one, because the structure is already leaky and responds quickly. But a wardrobe that has held clothes since 1978 needs to be emptied, washed down, dried fully and left open for days — not sprayed.Symptom to cause: old building or new
The same phrase — "my flat has a smell" — points at completely different mechanisms depending on the age of the building. Find the row that matches the actual note you notice.
| What you notice | Most likely cause | How to confirm it | What actually fixes it |
|---|---|---|---|
| Dry, mineral, faintly woody note that is always there ★ | The old structure itself — lime, brick, stone and timber | Notice whether it is present in an empty room with no furniture in it | Ventilate routinely; accept a low background and choose a blend that works with it |
| Sweet, slightly chemical "new" smell in a recent flat | Off-gassing from board, adhesive, paint, foam and flooring in a sealed envelope | Open everything for a day — if it drops sharply and returns when closed, this is it | Ventilate hard twice daily, run the exhausts, keep cabinets open; it fades over months |
| Old flat smells much worse on humid days | Absorbed odour re-released as the surface layer of old plaster takes up moisture | Compare a dry day with a wet one, in the same room, same time | Dehumidify or ventilate in dry spells; never dry washing in a closed room |
| A specific cupboard, loft or wardrobe reeks when opened | Decades of stored sorption in old timber and its contents, with no air movement | Open it and smell directly; compare with a modern wardrobe in the same flat | Empty it, wash it down, dry it fully, leave it open for days; reline if needed |
| Flat started smelling closed only after a renovation | The renovation sealed the accidental ventilation the old building relied on | Look for plastered-over ventilators, fixed glazing and a boxed-in bathroom vent | Restore or replace an air path; run mechanical extract where the openings are gone |
| Earthy, cellar-like smell with a tide line or chalky bloom on the wall | Water in the structure — a building defect, not an odour | Torch along the bottom of every external wall, behind furniture | Get the moisture source found and repaired. Do not fragrance this. |
| If none of these fit: empty one room completely for a day — furniture out, cupboards open, floor bare — and smell it. What is left is the building. What disappeared was the contents. That single test tells you which half of this article applies to you. | |||
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What to do in each kind of flat
In an old flat, work on moisture and on the absorbing surfaces. Ventilate on a schedule rather than by mood, because old buildings respond quickly to airing. Keep furniture a few centimetres off cool external walls so air can move behind it. Empty, wash and dry the old built-in storage — that is usually the single strongest source, and a lining of fresh paper or a fresh coat of paint inside an old wardrobe makes a real, permanent difference. If a room has decades of cooking or smoke in the plaster, sealing and repainting is not vanity, it is the actual fix: a modern primer and paint layer substantially reduces what the wall re-releases. What will not work is more cleaning of the surface, because the material is holding it, not the surface.
In a new flat, ventilate as if it were a job. The off-gassing is finite and falls off with time, but only air movement decides how quickly the concentration falls. Open two windows on opposite sides for ten minutes twice a day. Run the kitchen chimney and the bathroom exhaust routinely — most people never run the bathroom fan when not showering, and in a sealed tower it is often the only mechanical extract in the flat. Leave modular cabinets, wardrobes and drawers open when you are out. Wash new fabrics before use. If you have a mechanical fresh-air unit or a trickle vent, find out where it is and make sure it is actually open — in a startling number of new flats it has never been switched on.
Then, and only then, add the fragrance, and choose it for the building. An old flat carries a dry mineral and timber background, and a sweet floral fights that; something resinous or green sits over it and reads intentional. Mountain Breeze — Himalayan pine, sage and cedar — is the natural fit, with Evening Calm as the softer option in a bedroom. A new flat has an almost blank structural background, so it takes brighter and cleaner blends well: Morning Freshness or Garden Bloom. In terms of hardware, an old flat with high ceilings and leaky windows usually needs a full six reeds and often more than one point; a compact sealed new flat needs fewer — four reeds is often enough, because nothing is carrying the scent away. A reed diffuser from ₹749 covers a room up to roughly 150 sq ft at six reeds; the Sukoon at ₹1,899 with a Hotel Collection scent from ₹299 covers roughly 270 to 320 sq ft and gives you a switch instead.
The order that works
The steps are the same in both kinds of building; what changes is what each one means in practice. The purchase is still last.
| Step | What to do | When | Cost |
|---|---|---|---|
| 1. Remove the source | Old: empty and wash out old built-in storage. New: air new furniture, wash new fabrics, open every cabinet | Before anything else | ₹0 |
| 2. Move the air | Old: routine cross-ventilation, which works fast in a leaky building. New: ten minutes twice daily plus the exhausts | Daily, five to ten minutes | ₹0 |
| 3. Deal with what holds it | Old: seal and repaint heavily absorbed walls. New: nothing to seal — just keep moving air while it settles | Weekly to monthly | ₹0 |
| 4. Then the always-on layer ★ | A SOSA reed diffuser — a permanent background: six reeds and two points in a big old flat, four reeds in a compact new one | 50ml 6-8 weeks · 130ml 14-18 | from ₹749 |
| 5. Or the on-demand layer | Sukoon with a Hotel Collection scent — a switchable layer for a living room; covers roughly 270–320 sq ft with 3–6 drops a tank | Run it when you want it | ₹1,899 |
Versailles
I have lived in both, and I will admit a bias: I love the smell of an old building. That dry, faintly chalky, slightly woody note in a 1950s Bombay flat is not a fault to be corrected. It is the building, and any fragrance you put in should be chosen to sit alongside it rather than to argue with it. A sugary floral in an old stone-floored hall smells like a cover-up, because it is one. A cedar and pine blend in the same hall smells like a decision.
New flats need the opposite advice and they need it early. When you move into a new tower, everything in it is releasing something and nothing is leaving. I have walked into brand-new show flats that smelled far worse than a sixty-year-old building, and the owners were embarrassed because they assumed new meant clean. It does not mean clean; it means recent. Open the windows, run the exhaust fans, keep the wardrobes ajar for a month, and do not put a diffuser in the middle of it hoping to fix a smell that is a ventilation problem with an expiry date.
The thing I would tell both households is the same: fragrance is additive. It puts pleasant molecules into a room; it takes nothing out. In an old flat with damp in the wall, or a new flat still off-gassing at full tilt, a diffuser gives you two smells instead of one. Once the building is behaving, pick for the architecture — heavier and more resinous for old, cleaner and lighter for new — and let the room keep its own character underneath. A portion of every order funds a girl's classroom through Nanhi Kali.
Frequently asked questions
- High ceilings and hard-to-notice fragrance — the volume problem in old flats.
- Why a new high-rise feels stuffy — sealed envelopes and off-gassing.
- Why the ground floor is damper — earth-coupled slabs and capillary rise.
- Old large flat vs modern compact high-rise — two different fragrance strategies.
- Brand: the SOSA founder story.
SOSA products & prices (verified August 2026): Hotel Collection water-based ultrasonic diffuser fragrance 15ml ₹299 · 100ml ₹999 · 300ml ₹1,799 · Pack of 7 (15ml, all fragrances) ₹1,799; refills 100ml from ₹999. Seven scents: The Ritz-Carlton-inspired (white tea · bergamot · cedar), Westin-inspired (white tea · aloe · cedar), 1 Hotels-inspired (cedarwood · vetiver · green leaves), The St. Regis-inspired (amber · violet · woods), Shangri-La-inspired (jasmine · green tea · white tea), Four Seasons-inspired (citrus · floral · sandalwood), W Hotels-inspired (citrus · pepper · amber). Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499. Water-based, phthalate-free, composed to IFRA standards for home diffusion; 3–6 drops per tank. Made in India, Pune. The Hotel Collection scents are SOSA's own interpretations inspired by the world's finest hotels; all hotel names are trademarks of their respective owners and are used only to describe the scent style — SOSA is an independent Indian fragrance house, not affiliated with or endorsed by any hotel brand. Prices and availability subject to change — see the live product pages.