You can smell it, you cannot see it
Tracing a dead animal smell in a Hamilton house
Decomposition has a smell nothing else really imitates, so people are rarely wrong about what it is. Finding it is the hard part, and it is worth narrowing down before anyone starts opening things up.
Narrow it down first
- Walk the house and note where it is strongest, and at what height.
- Check whether it comes and goes with the heating or air conditioning running — that points at a duct run or a return.
- Look for flies gathering at one spot, or a stain on a ceiling. Both are close markers.
- Open the crawl space or attic hatch if you safely can, and note whether it is much stronger in there.
- Check outside as well. Under a deck, in a vent, in a window well or behind a soffit reads as an inside smell from the wrong room.
If it narrows to somewhere reachable
A crawl space, an attic, a duct that opens, a vent with a removable cover, a void with a hatch, a gap behind an appliance. That is a removal job and the smell ends when the source leaves. What reachable means in practice.
If it narrows to a sealed wall or ceiling
A small animal in a closed cavity cannot be reached without opening finished surface, and that is not offered here as a routine service. Nor is the opposite claim: nobody can honestly tell you a sealed-cavity smell always clears on its own by a fixed date, because how long it takes depends on the animal, the season and the airflow in that wall. Expect weeks rather than days, and treat any precise promise with suspicion.
What is actually worth a visit
Two situations. One, you have narrowed it to a reachable space and want it out. Two, you genuinely cannot tell which of the two situations you are in, and want someone to establish that before a decision gets made about opening anything. The second is a real and reasonable reason to call — it is the difference between a removal and a building repair, and it is better settled by looking than by guessing.
What will not fix it. Air fresheners, ozone machines and bowls of vinegar mask a smell while the source is still there. The smell stops when the source is gone, or when it has finished, and not before.