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Termination clearance for buildings with combustible and noncombustible exteriors.
Vertical Sidewall Installations
Important!
Minimum clearance between vent pipes and combustible materials is three inches (76mm) on top, and one inch (25mm) on
bottom and sides.
Important!
When vent termination exits through foundation less than 20" below siding outcrop, the vent pipe must extend outward so that
the horizontal vent terminal is located flush to, or beyond the outcrop siding.
Information on Various Venting Routes and Components
Important
: It is always best to locate the fireplace in such a way that minimizes the number of offsets and horizontal vent length.
Since it is very important that the venting system maintain its balance between the combustion air intake and the flue gas exhaust, certain
limitations as to vent configurations apply and must be strictly adhered to.
The graph showing the relationship between vertical and horizontal side wall venting will help to determine the various vent lengths allowable.
The horizontal vent run refers to the total length of vent pipe from the flue collar of the fireplace to the face of the outer wall.
The maximum horizontal vent run is 20 feet (457 cm) when the vertical vent rise is 8 feet (244 cm).
See Figure 20.
Venting terminals shall not be recessed into wall or siding.
Figure 36
RECESSED LOCATION
OUTSIDE CORNER
INSIDE CORNER
“A” = COMBUSTIBLE 9” (229mm)
= NONCOMBUSTIBLE 2” (51mm)
“F” = COMBUSTIBLE 6” (152mm)
= NONCOMBUSTIBLE 6” (152mm)
BALCONY
WITH PERPENDICULAR SIDE WALL
BALCONY
WITH NO SIDE WALL
“C” = CLEARANCE FROM CORNER
IN RECESSED LOCATION
COMBUSTIBLE 9” (229mm)
NONCOMBUSTIBLE 2” (51mm)
“D” = MINIMUM WIDTH FOR BACK WALL
OF A RECESSED LOCATION
COMBUSTIBLE 38” (965mm)
NONCOMBUSTIBLE 24” (610mm)
“E” = MAXIMUM DEPTH OF 48” (1219mm)
FOR RECESSED LOCATION
“G” = COMBUSTIBLE 9” (229mm)
= NONCOMBUSTIBLE 2” (51mm)
“H” = COMBUSTIBLE 18” (457mm)
= NONCOMBUSTIBLE 12” (305mm)
“I” = COMBUSTIBLE 18” (457mm)
= NONCOMBUSTIBLE 12” (305mm)
TERMINATION CLEARANCES
