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Something Died in the Wall. Now What?

Terrible smell in your house? A mouse likely died in the wall. Learn the decomposition timeline and how to use odor bags to survive the stench.

September 12, 2025 1 min read

Large metallic blow fly resting on a window sill

It starts as a faint, sweet, sickly smell. Three days later, it smells like rotting cabbage and death. You can't even sleep in the bedroom.

A mouse (or rat) ate poison and died inside your wall.

The Timeline of Stink

I have bad news. It's going to get worse before it gets better.

  • Days 1-3: Gas build-up. The smell starts.
  • Days 3-10: The peak. Fluids are leaking. Maggots are active. The smell is unbearable.
  • Weeks 3+: The carcass dries out. The smell fades to a musty cheese odor.

Can you find it?

Unless you see a wet stain on the drywall (gross, but it happens), you are guessing.

Option A: Cut the Wall. If you can pinpoint the smell to one stud bay, I can cut a hole. But 50% of the time, the smell is drifting from the attic, and we cut the wall for nothing.

Option B: Wait it Out. Use an "Earth Care Odor Bag" (volcanic rock). It absorbs the molecules. Coffee grounds and baking soda won't touch this smell. You need heavy-duty absorbents.

The Fly Warning

If you suddenly see big, slow black flies (Blow Flies) appearing in a closed room... the body is nearby. The maggots have hatched.