The design of heating, refrigeration, and air-conditioning equipment for buildings as well as components of the building thermal envelope depends on the principles of heat transfer theory. Heat transmission properties, such as thermal conductivity, resistivity, conductance, and resistance, for building materials and thermal insulation are important for the determination of heat transmission coefficients for these applications. The NIST Database on Heat Conductivity of Building Materials provides a valuable reference for building designers, material manufacturers, and researchers in the thermal design of building components and equipment. NIST has accumulated a valuable and comprehensive collection of thermal conductivity data from measurements performed with a 200-mm square guarded-hot-plate apparatus (from 1933 to 1983). The guarded-hot-plate test method is arguably the most accurate and popular method for determination of thermal transmission properties of flat, homogeneous specimens under steady state conditions. Several organizations, including ASTM and ISO, have standardized the method.
Version 2.0 of the database includes data for over 2000 measurements, covering several categories of materials including concrete, fiberboard, plastics, thermal insulation, and rubber. The data cover a temperature range corresponding to most building applications; however, the majority of the measurements were conducted at 24 °C (75 °F). The bulk densities of the test specimens range from approximately 4.2 kg·m-3 (0.26 lb·ft-3) to 2990 kg·m-3 (187 lb·ft-3) and the nominal thickness, in most cases, is 25 mm (1 in).Go Back