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Does A Cockroach Infestation Smell?

By July 8, 2023No Comments

If you’re starting to observe an unusual smell lingering around the house, it’s easy to suspect that there’s a roach infestation. Cockroaches are one of the most common pest infestations that produce a strange smell when there is a large number of them. A cockroach infestation smell is hard to describe but it’s an obvious sign of a cockroach infestation.

When you begin to notice a strange smell that doesn’t go away even after you’ve cleaned the entire house, you must start investigating where the smell comes from. Look for signs of a cockroach infestation and get rid of it right away before it gets worse. Remember, cockroaches and disease go hand in hand.


There are subtle signs and not so subtle signs of a cockroach infestation. You must know what these symptoms are to quickly trace where it’s coming from. It’s easier to get rid of the infestation once you’ve contained the source and magnitude of the infestation.

Here are the more noticeable symptoms of a cockroach infestation:

1. ODOR. A cockroach’s smell is difficult to describe but it’s very noticeable. A lot of people brush the smell as something to do with putrid moisture escaping from cupboard crooks or damp corners of the house. It’s perhaps because the smell of a cockroach infestation is hard to describe and can be inadvertently attributed to other smells.

However, once you begin to smell something unpleasant that is kind of musty and sweet but at the same time offensive, this is not something you can dismiss as any other smell. Trace the smell from under the sink, inside cupboards, kitchen corners, crawl spaces, or any moist places in your house.

2. SOUND. Contrary to what everyone believes, cockroaches do make a sound. The moment they start running around your kitchen past bedtime, you can pretty much observe the sound of their legs hitting the wood, granite, linoleum, or porcelain.

3. DROPPING. Cockroaches leave tiny crumbs much like Hansel and Gretel in a form of small black droppings. You can pretty much confuse these as ground black pepper. When you see these things scattered inside your storage areas, food cabinets, or near pet food, then that’s a sure sign of cockroaches feasting while you’re asleep.

4. EGG. Another clear sign of a pest infestation is the presence of cockroach eggs or what’s called ‘oothecae’ sacks. These egg cases hold an average of 16 cockroach eggs, and they’re very visible; littered or stuck inside dark and humid areas of the house as well as on major appliances, shelves, or bookcases.

On the other hand, when you start seeing cockroaches frequent around the house, slipping through every narrow corner or peeking through tiny openings, you must accept the fact that your house has been completely infested. It’s time to eliminate them before the cockroaches start infecting your household with diseases.


One of the most obvious signs of a cockroach infestation is the smell. Just how do you determine whether a particular smell is a sign of a cockroach infestation or simply just a rotten vegetable? Unfortunately, it’s a little hard to explain. The smell of a cockroach infestation is difficult to compare to. And, there’s not a single word that describes exactly what a cockroach’s smell like.

However, there’s a science to a cockroach’s smell. A collective pheromone found in the cockroach’s feces produces a distinct smell that can be sweet, heavy, and musky. On top of that, a chemical called cuticular hydrocarbon is used by cockroaches to communicate with each other. This chemical is found wrapped around a cockroach’s body—the legs, antennae, body, skin. This is pretty much what’s giving a cockroach its distinct smell.

Consequently, when cockroaches die, fatty acids called oleic acid, produce a putrid smell as dead cockroaches decompose. This smell is repulsive even for other cockroaches and insects making them move away from it.

Ultimately, scientific or not, you can observe a cockroach smell. The intensity of the smell will tell you whether the infestation is getting worse. The strangely sweet, musky, heavy, musty, pungent, oily, and offensive smell that increases in intensity as the infestation grows is a clear sign of a cockroach infestation. Your best option is to contact a pest management professional when you notice that the symptoms have become large-scale.


Among the 3,000 types of cockroaches around the world, there are 3 main types of cockroaches that exist in most Canadian homes—the American cockroach, the Oriental cockroach, and the German cockroach.

  • American cockroach – one of the largest cockroaches known to invade houses and commercial spaces in Canada. They are 35 to 40 millimetres long and are shining red-brown. Their wings are longer than their body, but they typically just run. Their ootheca can house up to 16 eggs that hatch in a month or two.
  • Oriental cockroach – these are smaller cockroaches that measure up to 25 millimetres long and are dark brown or black. Their wings are smaller and underdeveloped. These cockroaches can adapt to the natural environment and prefer to feed on decay, garbage, litters, and/or landfills.
  • German cockroach – these are the most common cockroaches you’ll see in every home. The German cockroach is notorious for its distribution around the world. They’re smaller, measuring 12 to 15 millimetres, and mostly found indoor. The German cockroach can also lay an average of 35 eggs in an ootheca and can multiply much faster inside humid and wet places around the house.

HOW DO YOU GET RID OF A COCKROACH SMELL? The best way to get rid of a cockroach infestation and the lingering smell is basic prevention. Thorough cleaning of the house, in every nook and cranny, is the best method to avoid a cockroach infestation. Clearing out the clutter, disposing of old newspapers and cardboard boxes, sealing cracks, and installing door sweeps are good prevention methods.

When the infestation has started, and the smell has filled the entire house, it’s time to find and kill the source. You can use pest traps and baits to kill cockroaches marching around the house. You can also use liquid concentrates and boric acid to deter cockroaches. These have been found effective and are good DIY methods as boric acid can be purchased. The best option however, tends to be boric acid as an effective deterrent.


Using store-bought chemicals and pest products can help you get rid of the infestation. Ultimately, you’ll need a professional pest management expert to take care of the job. GTA Toronto Pest Control can locate the source of the cockroach infestation and eradicate it. We are pest control experts in pest management in the city of Toronto.