Hearth and Home Technologies NorthStar-BK Position the Hearth Extension Finishing Material

C. Position the Hearth Extension		D. Finishing Material
	Position and secure the hearth extension over the protective		Do not install combustible materials over the metal
	metal strips that have been placed partially under the fireplace		face of the fireplace! This poses a safety hazard and
	front. These strips should be protruding approximately 2 in.		may start a fire. You may only use noncombustible
	(51 mm) from under the fireplace front and 2 in. (51 mm) on		material over the metal face of the fireplace. NOTE: The
	both sides of the fireplace opening. See Figure 18.1 on page		decorative fascia must be removable for future ser-
	18. Seal the crack between the hearth extension and		viceability of the Automatic Combustion Control.
	fireplace with a bead of non-combustible sealant. See	•	Combustible Material
	Figure 41.1. Apply a non-combustible finishing material of
	your choice to the hearth extension.		Materials made of or surfaced with wood, compressed
			paper, plant fibers, plastics, or other materials that can
	NOTE: SEE PAGES 10-12 & 38 “CLEARANCES TO COM-		ignite and burn, whether flame proofed or not, or whether
			plastered or un-plastered shall be considered combus-
	BUSTIBLES, HEARTH EXTENSIONS / FLOOR PROTEC-
			tible materials.
	TION” FOR CLEARANCES REQUIRED FOR DIFFERENT
	HEARTH EXTENSION INSTALLATIONS. THE CLEAR-	•	Non-Combustible Material
	ANCES MUST BE STRICTLY ADHERED TO.		Materials which will not ignite and burn. Such materi-
			als are those consisting entirely of steel, iron, brick, tile,
	WARNING		concrete, slate, glass or plasters, or any combination
			thereof.

Fire Risk		Materials that are reported as passing ASTM E 136, Stan-
• Hearth extensions are to be installed only		dard Test Method for Behavior of Materials, in a Vertical
as illustrated to prevent high temperatures		Tube Furnace at 750°C, shall be considered non-com-
from occurring on concealed combustible		bustible materials.
materials.		• Non-Combustible Sealant Material
• Hearth sealing strips prevent burning or
		Sealants which will not ignite and burn: Super Calstick
hot particles from inadvertently falling
directly on combustible surfaces in the		After completing the framing and applying the facing material
event the building should settle and
		(drywall) over the framing, a bead of non-combustible seal-
disturb the original construction.
		ant must be used to close off any gaps at the top and sides
		between the fireplace and facing to prevent cold air leaks.
		Large gaps can be bridged with fiberglass rope gasket.
		Only non-combustible materials may be used to cover the
		metal fireplace front.
		• Cardboard OR Metal Template
		A cardboard template of the front is printed on the outside
		of the shipping box. It measures 1/8 in. (3 mm) bigger all
		the way around than the actual front. Cut out the template
		along the outside of the line for use in your installation.
		A metal template is also available for more durable
		continued use remaining accurate over time. (See page 66.)
			WARNING
		Fire Risk
		•	Maintain clearances.
		• Use only non-combustible material below
			standoffs, material such as cement board is
Seal with			acceptable.
		• Framing or finishing material used on the front of, or
non-combustible		in front of, the appliance closer than the minimums
sealant
		listed, must be constructed entirely of noncombustible
Figure 41.1 Position the Hearth Extension
		materials (i.e., steel studs, concrete board, etc.).
September 1, 2008	Heat & Glo • NorthStar EPA Fireplace • 480-1081C			Page 41