I have spent a couple of hours looking at posts and trying to decide if I have a septic problem or a dead rat under my bathroom floor in the crawl space.

We have had a rodent problem in our attic and in our crawlspace and have put poison in both areas. We killed one critter in the attic, smelled the result in our bedroom and removed a dead rat from the attic. We are trying to figure out if we have another dead rat in the crawl space or if it is a plumbing/septic issue. There is a distinct odor coming from a utility bathroom off the kitchen. We went into the crawl space to find the decaying animal and couldn't find anything on the ground or in the area we suspected. There is insulation on the bathroom floor that appears to be "disturbed" but we couldn't find anything in the insulation. We didn't tear it down but can do so if we need to. The smell has been with us for about two weeks now.

I am wondering if there is a distinct difference between a SEWER SMELL and a DEAD ANIMAL SMELL... I don't want to start ripping down insulation if it is a septic issue. How can I rule out one or the other? I have noticed an increase in flies in the house which seems odd. Does this point to a dead animal vs. a septic issue?

I am stumped!