It s a bit of work but once you come directly on top of the spot with a dead rodent you will know it the smell changes.
Dead mouse in ceiling.
Along ceiling joists set two traps side by side with baits at opposite ends.
If you re too squeamish to undo a snap trap to release the dead mouse you can.
Set traps inside any drop ceilings and at.
If a dead mouse carcass is inside a wall or drop ceiling or any other inaccessible cavity the best method is to move back and forth with your nose against the wall or ceiling sniffing and sniffing.
Set snap traps along the mouse trails.
Typically a dead rodent mouse rat squirrel or other will emit a foul odor for a week to a couple weeks.
The good news is that you won t have to live with the smell of decomposition forever and you don t have to tear apart your wall or floors or ceiling or put the house up for sale.