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R
5100-I ACT WOOD INSERT
F. Hearth Extension
If the hearth extension is lower than the fireplace opening, the portion of the insert extending onto the hearth must be supported. Manufacturer designed adjustable support kit can be ordered from your dealer. Refer to page 23.
Hearth Extension Insulation Alternatives, R Value = 1.03
| k per | R per | Minimum | |
Material | inch | inch | thickness | |
| thick | thick | required | |
Hearth & Home HX3 & HX4 | 0.49 | 2.06 | 1/2 in. | |
USG Micore 300™ | 0.49 | 2.06 | 1/2 in. | |
USG Durock™ Cement Board | 1.92 | 0.52 | ||
Cement Mortar | 5.0 | 0.20 | ||
Common Brick | 5.0 | 0.20 | ||
Ceramic Tile | 12.50 | 0.08 | ||
Marble | 14.3 to | 0.07 to | ||
20.0 | 0.05 | |||
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Page 10 | April 21, 2010 |