Thermal Resistance Testing and Measurement Services

Thermal Resistance Testing and Measurement Services

Thermal resistance (R) is a measure of the resistance to heat flow in a material and is calculated by taking the thickness of the material and dividing it by its thermal conductivity. Thermal resistivity, which is the inverse of thermal conductivity, is a property of the material which is independent of its thickness. Thermal resistance is used to compare the performance of insulation products, such as foams and aerogels, which are often quantified in terms of their R-value.

Testing thermal resistance involves measuring the thermal conductivity of a material. For this, two transient and steady-state test methods are commonly used. Heat Flow Meter (HFM) is considered the gold standard approach to determining the thermal resistance of insulation and is capable of measuring thermal conductivity from -10 to 60 °C, with multi-temperature point measurements available to meet ASTM C518-17 specifications. Modified Transient Plane Source (MTPS) is also used for a range of materials, with the high-temperature MTPS configuration being especially suitable for testing insulation used in elevated-temperature applications.