Hearth and Home Technologies BIR42 Noncombustible, Framing Material, Equivalent insulation

Raised Hearth Extension Framing

The hearth framing must be constructed of non-combus- tible materials (Figure 12.2) and placed on 1/2 in. Durock and 1 in. Micore (or equivalent material) (Figure 12.4).

When creating the platform, allow for the thickness of the non-combustiblefinishing materials (Figure 12.5).

IMPORTANT! Hearth extension design must be determined before installation of fireplace.

Continuous, non-combustible sealant

Durock	Tile, stone or other	Fireplace
1 in. Micore or	non-combustible material
			Protective
equivalent insulation
(see Table)			Metal Hearth
			Strip

		*
			*
Floor constructed of wood or	* 2 in. (51 mm)
other combustible material

Figure 12.2 Hearth Extension Construction

Noncombustible	1 in. Micore or
Framing Material
	equivalent insulation
	& 1/2 in. Durock
Figure 12.4 Raised Platform Hearth Extension-Framing Materials

Note: The bottom of the fireplace opening is 3-3/4 in. (95.3mm) above the bottom of the fireplace. Finished hearth must NOT extend above this level.

20 in. Min.

Hearth Extension

Noncombustible

Finishing Material

Bottom of fireplace opening

Platform must be built to raise the bottom of the fireplace opening to the level of the desired hearth height.

Noncombustible

Finishing Materials

Figure 12.5 Raised Platform Hearth Extension-Finishing Materials

1 in. Micore or	Protective Metal
	Hearth Strips	Floor
equivalent insulation
& 1/2 in. Durock
	Noncombustible
	Framing Material

Figure 12.3 Raised Platform Hearth Extension Detail

42 Heatilator • Birmingham BIR42 • 4059-308 Rev F • 11/08