How to choose panels for cold rooms and freezers without guessing the thickness?

A distinction must also be made between storage and cooling or freezing of the product. These are different tasks for the installation. The wall area alone does not determine the required equipment capacity. The design should account for all relevant heat gains, not only transmission through the panels.

It is intended for rooms with controlled conditions. The detail of the joint and the way it is sealed are important. It should not be assumed that an identical thickness of a standard wall panel gives the same assembly. Documentation for the panel and a solution for the entire cold room are needed.

There are panels with a PIR core with low λ and cover widths adapted to the enclosure. Their maximum length is not the permissible ceiling span. Support and fixing must be selected separately. The ceiling should not be treated as a storage area or walkway without a suitable design.

These figures apply to one product family with a declared core thermal conductivity λ of 0.019 W/(m·K). Other panels may have different values. The figures alone do not determine which thickness suits a given operating temperature. The final choice depends on the heat balance, energy costs and how the cold room is built.

Also check the permitted temperatures for the complete product and its components. Seals, facings and service penetrations must operate in the same environment.

Assume an area of 50 m² and a temperature difference of 38 K. For U 0.16 the heat flow is approximately 304 W. At U 0.12 it is approximately 228 W. The difference is 76 W under the assumed conditions. This is solely the calculation U × A × ΔT for the specified area, not the capacity of the entire refrigeration system.

Door openings, goods, people and equipment add to the balance. The floor and thermal bridges must also be taken into account. Do not multiply the power difference by a year and call the result a certain electricity saving. Actual operation depends on usage time and system efficiency.

Warm, humid air can enter the cold zone through leaky joints. The result can be condensation or frost formation. A thicker core will not fix such a leakage path. The continuity of seals, corners and door connections must be designed. Materials must be selected for the temperature and cleaning method.

Cable penetrations and equipment fixings require separate details. They should not be cut after acceptance of the chamber without agreement. In a freezer, pressure differential control may also be important. The solutions for these elements result from the design, not from random selection of accessories.

The floor must carry traffic and loads while maintaining insulation. In a freezer, the risk of frost penetration into the substrate and the necessary protection must be assessed. A wall panel is not automatically a finished floor. The construction of the wearing layers requires separate selection.

Doors should match the temperature, intensity of use and dimensions of the goods being transported. Their tightness and opening time have a major influence on the operation of the chamber. Too small an opening hinders logistics, while an unnecessarily large one can increase air exchange. Selection is therefore also an operational decision.

Check the panel documentation, seals and penetrations. Establish the commissioning procedure in accordance with the system design. Monitor temperatures and locations where moisture appears. Acceptance should not end with the statement that the unit is cooling the air.

Prepare cleaning and maintenance rules. A change of goods or intensity of use may require a reassessment of the balance. Keep a description of the panels and details used so that later repair does not rely on fitting a random element. The tightness of the enclosure is required throughout the service life.