If you choose to wait it out, it can take up to 3 weeks to a month for the stinking odour to pass. After this time, the carcass has had enough time to completely dry out, and the rotting process has passed through its most noticeable phase. A decomposing mouse smells like propane gas or rotting meat.
Baken Soda & charcoal will remove the smell,coffee grounds & cinnamon will cover it up. You can use both.
Vinegar is a popular remedy for removing dead animal odors. It is known for its natural deodorizing properties. To implement this method, mix equal parts of water and vinegar in a spray bottle.
Use vinegar: Vinegar is truly the simplest solution to deodorize the space. Just fill in several disposable cups with vinegar and arrange them around the area where the dead animal was found. The vinegar can magically soak in all the bad smell leaving the space odorless and fresh. Use ground coffee or coffee filters:
The best solution for lingering smell from a dead rodent is professional duct cleaning. Pros can thoroughly scrub and disinfect most duct surfaces. This is often the best way to get rid of any lingering odors and offers peace of mind about bacteria or viruses the dead animal may have left behind.
Over-the-counter household cleaners and home remedies that can provide relief from foul dead animal odors include: Bleach – a powerful chemical that kills many microorganisms, bleach is almost too powerful as it can stain surfaces and cause an overwhelming odor of its own.
Steam clean carpets and upholstery; this is a powerful technique to remove deeply embedded pet odor. Use baking soda. Sprinkle it on carpets, pet bedding, or upholstery and let it sit overnight before vacuuming it up. Use diluted vinegar.
A bowl of vinegar can start absorbing odors almost immediately and is typically adequate for up to 24 hours. When left out in a room, the acetic acid in vinegar neutralizes alkaline odors, such as those from smoke, cooking, or pet accidents, by binding with the odor molecules and neutralizing them.
The smells coming from a dead animal are unpleasant, and they can often make you feel like you are going to be sick. However, simply smelling a dead animal is not likely to affect your health.
Bleach is excellent for eliminating foul-smelling bacteria, therefore both disinfecting any remnants of a dead rat in addition to removing the undesired smell. Your bleach mixture should consist of 10 parts water to one part bleach. Then, once you have that mixture, all you have to do is wipe down the area with it.
It is recommended that the dead animal be covered with lime or similar material prior to being covered with soil. This will aid in decomposition and reduce the potential for odors. In areas of high groundwater, animals cannot be buried within three (3) feet of groundwater depth.
You can use natural odor neutralizers, such as vinegar and baking soda to absorb foul smells. Vinegar is a natural disinfectant and can help absorb odors instead of masking them.
The temperature should reach 130o to 150o F for several days or weeks because at this temperature, microorganisms are active, decomposition proceeds quickly, and pathogens are destroyed.
It is usually difficult to remove them when they are inside a wall. A room deodorizer might help. The only way to get rid of the carcass would have to be by cutting into the wall. This may be difficult, as the odor may permeate through the walls and it is hard to localize the exact point to cut the wall.
Vinegar is also an amazing natural cleaning option for more serious pet odors. Try using vinegar (diluted with a bit of water) in a spray bottle and spray on carpets or floors. Or use in combination with baking soda on cushions or bedding for an extra powerful, odor-eliminating punch.
Homemade solutions: Baking soda and white distilled vinegar are natural deodorizers. Create a homemade spray solution of 50/50 water and vinegar or combine 1 teaspoon of baking soda with 2 cups of water. Use the spray near the stinky area to reduce the smell.
The damper the site, the longer the odor will last. For example, if a rat dies near a steam pipe, the smell can be horrible for weeks, but the odor from a dead mouse may last only a day. In fact, there may be no noticeable odor from a single dead mouse, but several dead mice in the same area could be a problem.
Neutrolene is a chemical neutralizer that permanently removes all organic odors on contact.
Follow the smell
Now comes the hard part. You see, the only way you can quickly pinpoint the spot is to get underneath your crawl space and follow the smell. Wherever the smell is most concentrated is most likely where the carcass is.
Dead animals are a threat to public health because of intolerable odors and the potential spread of diseases such as Salmonellosis, Campylobacter, Clostridium perfringens, and other zoonotic diseases.
A dead mouse should not be left to rot inside your wall, because its corpse could soon attract fleas. With an electronic borescope, you can locate the corpse's whereabouts by drilling a coin-sized hole, a few inches off the ground, into the drywall of the cavity that seems to be emitting the smell.