Built and installed new return plenum. Built and installed new supply plenums with existing zoning equipment. Installed 2 new return buckets with filter grills and cut in new supply bucket with new grill in master bedroom. Ran new flex back to the system to match the new buckets. Removed duct from distribution box going to master bedroom and made it home run to the supply plenum. Sealed all ductwork connections with mastic/hardcast. Tested system operation. Everything is working at completion of service.