TABLE OF CONTENTS The basic properties that determine the way in which a material will behave in the conductive mode of heat transfer are the thermal conductivity, k; the mass density ?; and the specific heat capacity C p. The last two properties are important when unsteady heat transfer is occurring because of heat storage. These variables are discussed in Chapters 2, 8, and 9 where the unsteady nature of the load is covered. The thermal conductivity is basic to the determination of the thermal resistance component leading to the U-factor.
Table 4.1 lists the basic properties for many different construction and insulation materials. The data given are intended to be representative of materials generally available and are not intended for specification purposes. It is always advisable to use manufacturers' specification data when available.
| Resistance [c] ( R) | ||||||
|---|---|---|---|---|---|---|
| Description | ? Density, lb/ft 3 | Conductivity [b] ( k) Btu in h ft 2 F | Conductance ( C), Btu h ft 2 F | Per Inch Thickness (1/ k), F ft 2 h Btu in | For Thickness Listed (1/ C), F ft 2 h Btu | Specific Heat, Btu lb F |
| BUILDING BOARD | ||||||
| Asbestos-cement board | 120 | 4.0 |
| 0.25 |
| 0.24 |
| Asbestos-cement board | 0.125... |
