Removing tobacco smell

Why the smell lasts for years

Cigarette smoke contains several thousand compounds, and two of their properties matter in practice. First, they are resinous and sticky — once they settle on a surface they do not fall off but form a thin, resin-like film. Second, part of them are semi-volatile: they slowly detach from that film back into the air for years. That is what produces a constant, self-renewing smell with no smoker in the room.

This film is virtually insoluble in water. Ordinary washing with a household cleaner does not remove it — it smears it in a thin layer over a larger area. That is why after a thorough “deep clean” the smell often stays much the same, or even becomes more evenly spread through the whole flat.

Why it is stronger in warm weather

A third property: evaporation depends on temperature. In summer and during the heating season, when walls and ceilings are warmer, the smell becomes noticeably stronger. Many people who buy a flat in winter only discover the problem in spring — nothing has got worse, evaporation has simply increased.

A nicotine film is not dirt on a surface — it is a deposit that slowly evaporates back into the air for years.

Where the deposits are heaviest

Warm smoky air rises, so the layer is uneven. If you clean only what you can see at eye level, you miss most of the source.

A simple self-test: take a white, damp microfibre cloth and wipe it across the ceiling in a darker corner. If the cloth turns yellowish-brown, the layer is thick and ozone treatment alone will not be enough. If it stays almost white, there has been little smoking and the situation is simpler.

How we remove it

The most important step on that list is the second one. Ozone treatment is powerful, but it oxidises what it can reach — not kilograms of resin sitting on the ceiling. If the layer is thick it has to be removed physically first, and only then does ozone treatment clear the remaining smell out of textiles, furniture and gaps.

Before letting or selling

Tobacco smell is one of the commonest reasons a flat does not get let, or does not sell for the price expected. Someone coming to a viewing notices the smell in the first few seconds, and it shapes their impression of the whole property — including how well it has been looked after in other respects.

In practice this means treatment before the listing goes live usually pays for itself — especially if the flat is being prepared anyway.

If renovation is planned, it makes sense to treat before the new finish goes on, not after. Painting over an untreated layer of deposits often lets the smell come through the new paint. If the finish is being replaced completely, the best moment is when the old wallpaper is off and the new is not yet up: bare walls take treatment much better.

Furniture is another practical question. If the flat is let furnished, it is the sofa, the mattress and the curtains that will bring the smell back faster than the walls will. They are worth treating at the same time as the room, rather than moving them out.

If the smell comes from neighbours

This is a separate situation worth recognising before any treatment: nobody smokes in your flat, yet a tobacco smell keeps appearing. It almost always arrives through the shared ventilation shaft or through gaps in the shared structure.

You can tell them apart by location. If the smell is strongest right at the ventilation grille, the source is the shaft. If it is strongest at a socket, behind the toilet by the riser or under the sink, air is crossing through an unsealed gap in the structure — and that gap can be sealed inside your own flat.

There is also a characteristic timing pattern: the smell arrives in waves, at particular hours, rather than as a constant background. That means you are noticing the moments when a neighbour smokes, not a build-up in your own flat.

What treatment can do about it

In this case we say it honestly: ozone treatment will remove what has already soaked into your textiles, furniture and finishes, but it does not stop the cross-flow. If air keeps coming in, the smell will return, and how quickly depends on the intensity of the flow. The riser is common property, and checking its draught is the property manager's responsibility; the solution starts with a written request, and it happens faster when several flats on the same riser complain. More on this on the Air disinfection page.

What people try and why it fails

There is also one limit that is fair to state up front. If a flat has been smoked in for thirty years and the deposits have soaked into porous, untreated wallpaper, gypsum plaster or fibreboard, no treatment will return the material to its original state. In those cases only replacing the finish together with treating what is underneath gives a lasting result, and we say so rather than selling three ozone treatments in a row.

Prices

Ozone treatment is €1.20/m², minimum €60. For surface treatment before ozone treatment we set the price after an inspection — it depends on the area and how heavy the deposits are.