Masonry Magazine June 1975 Page. 17
TABLE 1-Continued
Heat Transmission Coefficients of Building Materials
| Materials Description | Conductivity or Conductance | Resistance (R) |
|---|---|---|
| | (k) | (C) | Per Inch Thickness (1/k) | For Thickness Listed (I/C) |
| Insulating Materials | | | | |
| Batt or blanket | | | | |
| 2 to 24 in. | | | | 7.00 |
| 3 to 3½ in. | | | | 11.00 |
| 54 to 6½ in. | | | | 19.00 |
| Boards | | | | |
| Expanded polystyrene | 0.19 | | 5.26 | |
| Expanded polyurethane | 0.14 | | 7.14 | |
| Loose fill | | | | |
| Vermiculite 4 to 6-lb density | 0.44 | | 2.27 | |
| Perlite | 0.37 | | 2.70 | |
| Woods | | | | |
| Hard woods | 1.10 | | 0.91 | |
| Soft woods | 0.80 | | 1.25 | |
| Metals | | | | |
| Steel | 312.0 | | 0.003 | |
| Aluminum | 1416.0 | | 0.0007 | |
| Copper | 2640.0 | | 0.0004 | |
From ASHRAE Handbook of Fundamentals, except as noted.
Face brick and common brick do not always have these specific densities. When the density is different from that shown, there will be a change in the thermal conductivity.
Calculated data based upon hollow brick (25% to 40% cored) of one manufacturer. Based upon coring and density given. R figure based upon coring and density of supplier using parallel path method. Vermiculite fill in cores.
From NCMA TEK 38.
Values for metal siding applied over flat surfaces vary widely depending upon the amount of ventilation of air space beneath the siding, whether the air space is reflective or non-reflective, and on the thickness, type, and application of insulating backing-board used. Values given are averages intended for use as design guide values and were obtained from several guarded hot-box tests (ASTM C 236) on hollow-backed types and on types made using backer-board of wood-fiber, foamed plastic, and glass fiber. Departures of ± 50%, or more, from the values given may occur.
Thicknesses can vary. R values must be stamped on batt.
Based upon values as commercially produced. For calculations use specific manufacturer's specified values.
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