In addition to low-humidity air, what can a restorer do to dry restorable subfloor under...

The IICRC WRT body of knowledge explains that drying restorable subflooring beneath ceramic tile is challenging because tile and grout assemblies havelow permeability, restricting vapor movement. In such conditions, evaporation must be enhanced by manipulating the remaining controllable variables—most notablytemperature.

Increasing the temperature of the wet materials raises the vapor pressure within the subfloor, which increases the vapor pressure differential between the material and the surrounding air. This differential is the primary driving force that moves moisture out of materials and into the air. The WRT manual emphasizes that warmer materials evaporate moisture more readily, provided ambient air vapor pressure remains lower.

Lowering dehumidifier output temperature or increasing relative humidity would reduce drying efficiency. Air filtration devices address airborne particulates and do not directly influence evaporation. Therefore, controlled heat application—within safe limits—is a recommended strategy when drying beneath low-permeance floor coverings.

The WRT curriculum reinforces that effective drying requires managinghumidity, airflow, and temperature together, particularly when materials restrict vapor transmission.