Osburn OB02401 - Manual (Page 10)

10
2.6 Positioning the unit
In addition to ensuring compliance of the masonry fireplace hearth extension (see Compliance
of the masonry fireplace in Section 2.3), it is necessary to have a floor protection made of non-
combustible materials that meets the measurements specified in table FLOOR PROTECTION
(see Section 2.7). To determine the need to add a floor protection (D) beyond the hearth
extension, you must do the following calculation using the data in Table Data for floor
protection calculation of this section: D = B - (A - C). If the value (D) is negative or zero, you
do not have to add more floor protection in front of the unit, because the masonry fireplace
hearth extension is long enough. If the value (D) is positive, you will need a floor protection in
front of the hearth extension at least equivalent to the result (D).
Here is a sample calculation to determine the need to add a non-combustible materials floor
protection. For someone living in the USA whose fireplace opening is less than 6 ft
2
and which
the insert would protrude 3" (76 mm) into the room (C) the calculation would be:
Value D = B - (A - C)
Value D = 16" - (16" - 3")
Value D = 16" - 13"
Value D = 3"
This person should install a non-combustible floor protection of at least 3" (76 mm) in front of
the fireplace hearth extension.