Styrofoam™ Brand Panel Core 40
| Can be used under almost all weather conditions | |
| Enhanced productivity | |
| Can be used in wet cavity wall environments | |
| High moisture resistance | |
| Long-term thermal performance |
|   | Method | Unit | Value |
|---|---|---|---|
| R-value per in., min<sup>2</sup> | C518 | per inch (25 mm), °F•ft2•h/Btu, fresh @ 55°F (13°C) min. per inch (25 mm), °F•ft2 •h/Btu, fresh @ 20°F (-7°C) min | 5 |
| Compressive Strength, min.<sup>1</sup> | D1621 | psi, min., vertical | 40 |
| Flexural Strength, min.<sup></sup> | C203 | lb/in2 , min., extruded | 75 |
| Water Absorption, max.<sup></sup> | C272 | % by volume | 0.3 |
| Water Vapor Permeance, max.<sup>4</sup> | E96 | perm, max | 1.5 |
| Dimensional Stability, max<sup></sup> | - | % linear change | - |
| Coefficient of Linear Thermal Expansion<sup></sup> | - | x105in/in °F (x102mm/m °C) | - |
| Complies with ASTM C 578<sup></sup> | C578 | Type | X |
| Maximum Use Temperature<sup></sup> | - | °F (°C) | - |
| Flame Spread<sup>3</sup> | E84 | - | 15 |
| Smoke Developed<sup>4</sup> | E84 | - | 165 |
1Vertical compressive strength is measured at 10 percent deformation or at yield, whichever occurs first.
2 R means resistance to heat flow. The higher the R-value, the greater the insulating power.
3These numerical flame spread and smoke developed ratings are not intended to reflect hazards presented by this or any other material under actual fire conditions.
4R-values are consistent with criteria of ASTM C578 and the requirements of the FTC R-value rule (16 CFR Part 460)