Where the smell hides in a home

People describe this as the smell being “in the walls”, and they are closer to right than they think. It is just rarely the walls.

Smell is not a mood, it is a material

An odour is coming off something. Find the something and remove it and the odour goes with it. Treat the air and the something is still there.

So the whole job is locating the source, and the source hides in a small number of very predictable places.

The usual places, in the order we check them

• Soft furnishings. Mattress core, sofa foam, pillows, bedding, rugs and curtains. These are built to absorb and cannot be cleaned through.
• Under the floor covering. Not the floor, the layer beneath it. Underlay, adhesive and the screed take in what the surface only passed along.
• Behind and under skirting. The single most missed place in any room. There is a gap there by design and fluid finds it.
• Grout and joins. Tile faces are sealed, grout lines are not. A floor can be spotless and the lines between it still holding.
• Under fixed furniture. Wardrobe bases, bed frames, the dead space behind a headboard. Worked around rather than opened up on a rushed job.
• Ventilation and air-conditioning. A room that smells fine until the fan comes on is telling you exactly where to look.
• Drains and traps. Sometimes the honest answer is a dry trap and not the thing everyone is afraid of. It is worth ruling out early.

Why the marks are a poor guide

Fluid follows gravity and it follows gaps. The visible mark is where it landed, not where it ended up, which is why the affected area is usually larger than the stain and occasionally in a different room.

We do not chase the stain. We work out where it went, which is not a question a photograph can answer.

This is why we come and look

One of the directors attends and assesses the space in person, because half of the list above is invisible from the doorway and none of it can be judged over the phone. A company willing to quote a remediation from a description has decided not to find out.

What happens once it is found

Absorbent material is removed rather than treated, what stays is treated and checked, the waste leaves through the proper channel, and then the space is cleaned as its own step.

More on why covering it fails in why air fresheners do not remove the smell, and the full order of work is on What happens now.

The neighbouring rooms are worth checking too

Odour does not respect the door of the room it started in. It moves with air, and air moves through a home along routes nobody thinks about: under doors, through service ducts, up a riser, along a shared ceiling void.

So a smell that is strongest in the kitchen occasionally has nothing to do with the kitchen, and a room two doors away can hold it long after the source room is finished.

That is also why it is worth finding out whether a neighbour has noticed anything, awkward as that is. It is information, and it can tell you which way the air has been travelling.

What we do when nothing obvious turns up

Sometimes the list runs out and the room still smells. At that point the honest options are opening something up, or accepting that the source is somewhere we have not yet been able to reach, and saying so.

We would rather tell you that than treat the room again and charge you for the same guess twice. If the answer is that the problem is not in your property at all, that is covered in the smell is coming from the unit next door, and the flooring question is in when flooring has to come up.