Installed new 10" return flex run in attic space. Tied into existing return plenum and ran flex across attic. Cut into open Sheetrock in kitchen area to install return box and grill. Mastic sealed all connections on new return run. In crawl space removed section of damaged 8" flex. Connected new flex to existing ductwork. Test system operation, system is fully operational at time of service. Recommended flood protection, wrapping return plenum and duct cleaning.