Cut 4” main stack in basement and installed a 4x6” patch liner 3’ in length to cover a hole on the upstream side of the 6” elbow. Installed pvc stack section that we cut out with non shear mission couplings. Broke up concrete floor around 2” line going into ground in order to provide access for installing patch liner. Installed a 4x6” patch liner 5’ in length covering the hole just downstream of the 6” elbow. Installed new section of 2” pvc and backfilled hole with 3/4” stone and cemented floor.