How To Eliminate The Need Of A R Value - Osburn STRATFORD Installation Instructions Manual

In the case of a known K and thickness of alternative materials to be used in combination,
convert all K values to R by dividing the thickness of each material by its K value. Add the R
values of your proposed materials as shown in the previous example.
Example:
K value = 0.75
Thickness = 1
R value = Thickness/K = 1/0.75 = 1.33

2.4.2.2 How to eliminate the need of a R value

It is however possible to eliminate the R value by elevating the unit from 4'' above the floor (see
Figure 9), but the joint between the extension of the hearth and the fireplace must be protected by
a non-combustible material. For example, a sheet metal (not included) as illustrated in Figure 9
(B). Please note that a combustible floor protection of at least 16" long must be installed in front
of the fireplace as illustrated in Figure 9 (A).
Figure 9
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