Saw this during an inspection today. 1,440 sq ft, built in 2010 on a slab, connected to a sewer. There is a sewer cleanout on the front of the house, but on the back of house I saw the pipe pictured on the back.
Tha lid came off and there was a plastic screen/vent. One the screen/vent was removed it revealed, what appeared to be, a 4-inch pipe that when back under the foundation. I’ve never seen anything like this before. Any ideas what it might be?
Hey Dave, that thought crossed my mind, but there wasn’t a fan of any type observed, and there was no air coming out of the pipe. Also, I believe mitigation systems are supposed to terminate above the roofline.