Dead Mouse Or Rat Smell In The Wall
- How urgent
- Low risk
- Who fixes it
- A pest controller
What's happening?
A dead mouse, rat, squirrel or bird in a void gives off a strong, sweet, rotten smell that is worst nearest the body. There is no reliable figure for how long it lasts: it fades as the body dries, and removing the body is the only way to end it. Flies and maggots appearing in one spot are a further sign. If you are not sure it is an animal, a gas or drain smell is a different problem and belongs with a gas engineer or drainage engineer.
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What usually causes it?
- A mouse or rat that died in the wall cavity, under the floorboards or in the loft
- A bird or squirrel that fell down a chimney or into a void
- A bat that died in a roost, which needs different handling
- A dead animal in a drain or under decking or a shed, smelling indoors in warm weather
Is it dangerous?
The smell is unpleasant, and low risk in itself. The risk is handling: rodent urine can carry leptospirosis, which the NHS says is spread in the pee of infected animals, most commonly rats and mice. Wear gloves, do not touch a body with bare hands and wash your hands afterwards. If it is a bat, do not touch it with bare hands: the Bat Conservation Trust runs a dead bat scheme for rabies testing and sends a pack on request.
Can I fix it myself?
Follow your nose to the spot it is strongest and check the nearest accessible place: under a cupboard or kitchen unit, behind a bath panel, in the loft by the eaves, or under a floorboard that lifts. If you find the body, wear gloves, bag it, double-bag it, bin it and clean the area with a disinfectant. Ventilate the room. If you cannot reach it, it is in a cavity: do not break open walls yourself. Ask your council or a pest controller.
When should you call a pest controller?
Call a pest controller or your council when the smell is in a wall cavity, floor void or under fixed units, when you cannot find the source, or when the smell has lasted longer than a few weeks. They can also tell you whether the rats or mice are still active.
What will the pest controller actually do?
- Trace the smell and lift accessible boards or panels to reach the body
- Remove the carcass and any contaminated insulation, and bag it for disposal
- Disinfect and deodorise the area
- Confirm whether the infestation is still active and treat it, then proof the entry points
Who fixes this
- Dead animal removal
- Mice and rat control
Questions people ask
How long does a dead mouse smell last?
Is the smell of a dead animal harmful to health?
How do I find a dead rat in the wall?
Sources & References
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