1. Begin the Material Selection Process

Narrow the material selection based on the specific application (Figure 1). Base the decision on criteria such as temperature, smoke and fire, moisture requirements, installation cost, and energy efficiency.

2. Design for the Process Operating Range

Don’t just compare data sheets. For simplicity, k-factors often have a default of 75°F mean temperature. However, the use of a single point could lead to an inferior choice depending on the temperature range of the process (Figure 2).

3. Evaluate Cost

Once the proper material is selected for the temperature range, thickness becomes the major cost factor. Use 3E Plus Software to calculate thickness. Ask your installation manufacturer to provide the current thermal data of its material for use with the software. Remember, thickness means more:

• Insulation material;

• Joint sealer;

• Mastic;

• Vapor barrier;

• Protective jacket; and

• Support hangers.

4. Design for Thermal Drift

There is no need to design for thermal drifts with rigid foams. Manufacturers have designed products that enhance thermal performance and make thermal drift negligible in rigid foam after 180 days, when k-factors are tested and reported (Figure 3).