Originally Posted by Ken 297
If you have checked all the traps and toilet seals and can't see any open pipes a smoke bomb will certainly tell you if there is any open joints.
Are you sure its coming from the sewer pipes?
Is it a constant smell or can you detect a pattern of when the smells occur.
ie. hot weather, rainy weather.
I have found several different sources of "sewer smells" in houses.
The most common cause is a blocked mainline sewer. This doesn't seem to be the problem here.
Some of the other problems I have found include, rotten meat that someone forgot to put in the freezer, cat litter boxes, stagnant water in the floor drains, something in the heat vents, sump pumps that are operating sporadically, rotting vegetation around window wells.
Good luck tracking it down.