Vermiculite insulation that comes from a particular mine before 1990 is likely to contain asbestos. This is particularly true in the U.S. However, not all types of vermiculite insulation contain asbestos. Since you can't detect the presence of asbestos without special equipment, it's best to assume that the insulation contains the dangerous mineral and to either leave it alone or hire a professional to handle it.

There are products that still contain asbestos, but they were typically installed decades ago. Common places where you may still find asbestos-containing materials are in siding, wrapped around ductwork, in older appliances (i.e., stove and gravity furnaces), and in floors. Asbestos was primarily used as an insulator, so anywhere in an older home where you lose heat is where you will most likely find asbestos.

If asbestos is found, it is crucial to consult with a professional. They will provide recommendations for appropriate abatement actions, which may include safe removal, containment, sealing, or enclosure. All actions must be planned and executed in accordance with local regulations for handling asbestos.

While a professional can always help, there are some common plumbing culprits you can check yourself to see if you can find the sewer gas smell. For example, you should check your water traps, sometimes called P-traps and S-traps, which are located under sink, shower, and laundry drains. The wax ring beneath the base of your toilet, which creates a watertight seal with the plumbing, could also have gone bad.