Specifications

4.3.1 Mantel Clearances
4.3.2 Hearth and floor protection requirements:
• When the bottom of the fireplace is installed less than 3 1/2” (88 mm) to the floor, the floor
requires thermal protection of 3/4 inch (19 mm) thick mineral fiber millboard with a value of
k=1.12 BTU/IN FT
2
HR
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F. The protection must extend forward 24 inches (610 mm) and 8 inches
(203 mm) to each side of the door opening.
• When the bottom of the fireplace is installed less than 7” (177 mm) but more than 3 1/2” (89
mm) from the floor, the floor thermal protection only needs to be 1/2 inch (12.5 mm) thick
k=1.68 BTU/IN FT
2
HR
o
F. The protection must extend forward 24 inches (610 mm) and 8 inches
(203 mm) to each side of the door opening.
• When the bottom of the fireplace is installed 7” (178 mm) or greater from the floor, the floor
only needs to be covered with non-combustible material, minimum 3/8 inch (10 mm) thick
extending forward 16 inches (455 mm) and 8 inches (203 mm) to each side of the door opening
in the U.S. (In Canada: 18 inches / 407 mm).
To substitute alternate insulation material, you need to know the “k” factor for that material, and
calculate the required thickness for the alternate material; use the following formula:
Example: “K” value of brick = 5
4.5 inches of brick is required to meet the requirement.
”K”/ 0.84 *(specified thickness)
5/084*0.75 = 4.464 inch
3 inches of brick is required to meet the requirement.
5/084*0.50 = 2.976 inch
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