Eliminating the smell of a dead rat requires removal of the carcass, followed by efforts to cover up or neutralize the smell until it dissipates on its own. Dead rats are often found behind walls or in plumbing systems, so it can be difficult to locate the source of the odor.
The smell of a dead rat lingers until decomposition is complete, which can take more than 3 weeks.
Step 1: Eliminate the carcass
If possible, find the dead rat to eliminate the source of the smell. Look for flies, maggots, or damp spots on the wall or ceiling. It is extremely expensive to tear up a house in search of a dead rat, so other remedies might become necessary.
Step 2: Purify the air
Air cleaners sometimes help lessen the smell of a dead rat. They filter the air to remove particles that cause offensive odors. Although they cannot completely eliminate the odor, they can lessen the impact on residents of the house.
Step 3: Neutralize or mask the odor
Odor neutralizers employ bacteria to break down odor-causing compounds in the air, while odor masking agents release a pleasant smell to cover up the smell of the dead rat. Neutralizers are more effective, but masking agents are easier to find and use.