It is best to frame your appliance after it is positioned. Use 2x4's and frame to local building codes.
4.1
MINIMUM CLEARANCE TO COMBUSTIBLES
Combustible protrusions such as mantels and shelves may occur at or after a minimum distance of 2" away
from the side of the appliance. Thereafter, the depth of any protrusions must be of equal to or less than the
distance from the side of the appliance up to a depth of 6", after which no greater clearance than 6" is required.
This can be considered a side wall with no length boundary.
Minimum clearance to combustible construction from appliance:
sides, back, bottom and top of the unit
recessed depth
36
13
/
"
1
2
3
/
"
4
35
/
"
3
4
0 inch
13 1/2 inches
OUTSIDE
CHASE
3"
5
/
"
1
2
37
/
"
3
4
37
7
/
"
8
13
/
"
1
2
PROTRUSION
W415-0297 / P / 02.03.12
11
13
1
/
"
2
INSIDE
CHASE
2"
4"
SIDE
2"
WALL
4"
6"