Concrete flooring in today’s industrial freezer spaces should easily outlast all other parts of the facility. A typical serviceable lifespan can reach 50 years or more. However, the floor often is overlooked when it comes to maintenance as many people ignore things that are not at eye level or seem rugged in construction. Without regular preventive maintenance of the under-floor heating system, though, the ground can freeze, allowing freezer floors to heave and crack, resulting in significant repair costs and even the loss of the entire facility.
Stellar, a design, engineering, construction and mechanical services firm that specializes in low-temperature facilities, has seen many floors in need of significant repair. Throughout its 25 years designing, building, renovating and repairing low-temperature facilities, Stellar has witnessed first-hand how the lack of regular preventive maintenance of freezer floors can lead to catastrophic and dangerous conditions, including building code violations and the complete destruction of the facility. Stellar likens freezer floor maintenance to oil changes in cars – with regular maintenance, significant damage and costs can be avoided. By repairing problems as soon as they are identified – rather than waiting – considerable savings can be achieved.
In any freezer, the under-floor soil must be heated to ensure it remains above 32°F for the life of the facility. This typically involves one of three types of heating systems – vent tubes, which draw in outside air that is circulated through the tubes buried in the soil; electric heat; and heated glycol, which runs through tubes in the soil.
Problems arise when the heating system malfunctions and stops heating the soil beneath the facility. Without the heat, the extreme cold in the concrete floor can transfer through the concrete, past the insulation and sub-slab and into the soil. Once this occurs, the moisture in the soil becomes ice, which expands and forms an ice lens (which looks somewhat like a flying saucer in shape). This lens pushes upwards, buckling and heaving the concrete floor above it. This phenomenon, called “frost heave,” causes logistical issues and safety concerns that can seriously disrupt a facility’s operations. Left unabated, the ice eventually can affect foundations, which in turn can compromise structural members. The formation of ice below a facility with a non-functioning under-floor heating system can occur very rapidly, depending on the moisture in the soils and the severity of the winter climate where the facility is located.
Check out the September 2020 edition of Refrigerated & Frozen Foods: Cold storage construction and COVID-19, how foodservice is adapting to coronavirus challenges, SugarCreek, 2020 cold storage construction guide & directory and much more!