Yes, cork can be used under a concrete slab. Cork is generally not appealing to pests such as termites. It contains suberin, which repels termites and other insects. It also has low cellulose content, which makes it an unattractive food source for termites (compared to wood, which has cellulose). Expanded cork has good moisture resistance due to its suberin content, which prevents rot and mold growth.
While different from
expanded insulation cork, extruded composition cork has been used extensively under airport runways and other concrete paving applications. Our self-expanding cork is designed for use in water-retaining structures such as dams, reservoirs, sewage works, sea walls, and swimming pools.