Sewer video inspection service call. Televised sewer from outside clean out near sidewalk back to house. Sewer was not backed up at all but had heavy roots t the cast to clay. Pushed into cast iron and saw check valve that is buried in crawl space. Located additional overhead line that is where the main stack is running through that tees into this line just outside foundation wall. this line was all backed up due to roots. Duct outside to expose line approximately 6” deep. Cut a window on the cast iron then Rodded from there to open line. Completed sewer repair steps.