Installation Guide
Page 16 
7.  Next construct the hearth extension out of non-combustible inorganic building materials as follows: 
a)  The hearth extension must extend 16" from stove door opening . 
b)  The hearth extension width must be at least 37 1/2". 
c)  The hearth extension must be made of brick 2" thick, a listed “Hearth Extension” or “Floor Protector”, or 
a hearth extension made of non-combustible inorganic material with a K* factor of: 
K = 2.5 BTU ((HR) (ft
2
) (
o
F/in.)) or R-Value R=0.6 See Page 6 for formula. 
ALTERNATE FLOOR PROTECTORS MATERIALS 
With the floor protector or hearth extension material specified as one layer of 2" thick brick with a K* factor of 
5.0, you may use alternate materials as long as the K* factor (s) is calculated as follows: 
  Formula: Required thickness = (K of alternate material/K of millboard) X (thickness of millboard) 
  Example: An alternate inorganic non-combustible millboard with a K of .9375 would require a thickness  
     as follows: 
    Required thickness = .9375.0
o
 x 2 inch 
         = 3/8 inch 
FIGURE 14  CHASE ENCLOSURE AND CORNER LOCATION FRAMING 
 Optional 
Fire Code Sheet Rock 
And Metal Fire Stop  
Ceiling 
RADIATION 
SHIELD 
 15FT. 
 MAX. 
2 In. 
Min. 
Chase 
Enclosure 
TOPPER 
STORM COLLAR 
ROOF FLASHING 
TRIPLE WALL PIPE 
2 " X 4" STUDDING 
USE FIRE CODE SHEET ROCK 
OPTIONAL METAL FIRE STOP 
RADIATION SHIELD 
2" X 4" STUDDING 
A SINGLE HEADER MUST BE 
INSTALLED ABOVE CABINET  
34 3/4" 
THESE MEASUREMENTS 
ARE CRITICAL 
WARNING: Install the hearth protec-
tor only as specified. The hearth exten-
sion must extend a minimum of 16" in 
front of stove door opening and must be 
37 1/2" wide minimum. (See Page 5) 
CAUTION: Refer to chim-
ney manufacturer’s instruc-
tions for assembly and disas-
sembly of chimney parts. Be 
sure to follow chimney 
instructions for proper clear-
ances to combustibles and 
proper air spacing required. 
NOTE: Follow building and fire codes  
 for each individual state. 
“A MINIMUM OF 30.5" 
FROM TOP OF STOVE 
TO TRIM OF  
MANTEL or SUPPORTS” 
30.5"
37 1/2" 










