Serviced exposed HVAC ductwork in Roselle residence. System inspection revealed significant air leakage at three main junction points in the basement area. Approximately 23% energy loss calculated. Removed existing deteriorated mastic sealant. Cleaned all surfaces properly. Applied professional-grade aluminum tape reinforcement followed by mastic sealant application at all seams and connections. Performed smoke test to verify proper sealing. System now operating at optimal efficiency with improved airflow to all rooms. Estimated 15-20% reduction in energy costs expected.