How Underground In Slab Ductwork Was Restored Without Excavation in Country Club Hills, Illinois
Project Timeline: October 2025 – January 2026
The Challenge
An in-slab air duct inspection conducted in October 2025 revealed extensive deterioration of the home’s galvanized metal ductwork. Years of exposure to moisture had caused severe corrosion throughout the system. Several sections were beginning to collapse, and every portion of the ductwork showed significant compromise. Groundwater concerns were identified as a contributing factor.
Replacing the ducts would have required invasive excavation of the home’s flooring, creating major disruption and cost for the homeowner.
The Solution
After reviewing the findings and recommendations, the homeowner approved a trenchless duct restoration solution. All ductwork was located within the home's floor, allowing the entire restoration to be completed without excavating the slab.
The system was accessed through existing room registers and an access point at the furnace. The ducts were thoroughly cleaned to remove debris and corrosion. Trenchless Casting was then applied to restore structural strength and stability to the compromised ductwork.
After an overnight curing period, a full spray lining was applied to encapsulate the entire duct system. A second spray lining application was completed one week later to ensure long-term durability and performance.
The Result
The in-slab air duct system was successfully saved and fully restored. The ducts are now structurally sound, eliminating the risk of collapse and improving overall system integrity. In addition, the sealed and restored ductwork has helped improve indoor air quality for the homeowner.
This project demonstrates how trenchless air duct restoration can provide a cost-effective, non-invasive alternative to full duct replacement—restoring performance, extending system life, and minimizing disruption to the home.
