In the last two homes I inspected there was an open ABS in one & PVC in the other. Both were on the foundation slab near the floor drain (both were approx. 4 feet away). Both homes had the same material for waste stacks. I could not follow either for more than a few feet before they ascended into the ceiling and became non visible. I did not see these in the attic space, nor exhausting to the outside. What are these for?
Gadget Home Inspections