Termination 10 ft (3 m) or Less From Ridge, Wall or Parapet
A. 10 ft (3 m) or less
B. 2 ft (61 cm) minimum
C. 3 ft (91.4 cm) minimum
Termination More Than 10 ft (3 m) From Ridge, Wall or
A. More than 10 ft (3 m)
B. No height above parapet
required when distance from
walls or parapet is more than
10 ft (3 m).
C. 3 ft (91.4 cm) minimum
D. Wall or parapet
E. Wall or parapet
F. Height above any roof surface
within 10 ft (3 m) horizontally
G. 10 ft (3 m)
H. 2 ft (61 cm) minimum
Check 2—Any Solid or Liquid Fuel Appliances Vented into
This Chimney Channel
Solid fuel appliances include fireplaces, wood stoves, coal
furnaces and incinerators.
Liquid fuel appliances include oil furnaces, oil-fired boilers and
oil-fired water heaters.
Appliances which burn propane (sometimes referred to as LP
[liquefied petroleum]) gas are considered gas-fired appliances.
Check 3—Chimney Crown Condition
Damage from condensate normally appears first in the crown. If
any of the following trouble signs are present, the condition of the
crown is not satisfactory.
Crown leaning—"Fix 3—Rebuild the Crown"
Bricks missing—"Fix 3—Rebuild the Crown"
Mortar missing—"Fix 3—Rebuild the Crown"
Tile liner cracked—"Fix 4—Relining"
No tile liner—"Fix 4—Relining"
Salt staining at mortar joints (white stains and mortar
becomes sandy and/or erodes)—"Fix 4—Relining"
IMPORTANT: It may be necessary to follow both "Fix 3—Rebuild
the Crown" and "Fix 4—Relining."
Check 4—Debris in Cleanout
A cleanout (dropleg) must be in a location where the upper edge
of the cleanout cover is at least 12" (30.5 cm) below the lower
edge of the lowest chimney inlet opening.
A chimney without a cleanout could become partially blocked by
debris. If no cleanout is present, the chimney must be relined (Fix
4—Relining). Remove the cleanout cover, and examine the
cleanout for debris. If significant amounts of any of the following
are found, reline the chimney (Fix 4—Relining).
Fuel oil residue
Mortar or sand
Pieces of the tile liner
Rusted pieces of the metallic liner
Check 5—Liner Condition
If a metal liner is present, it must be checked. It cannot be
assumed that all existing metal liners are correctly installed and in
Remove the lowest existing vent connector and examine the
inside of the elbow or tee at the base of the liner. A small amount
of soot may be considered acceptable, provided the installer
vacuums it away. If rusted pieces of the liner have collected here,
the metal liner must be removed and replaced (Fix 4—Relining).
Next, gently tap the inside of the liner with a Phillips screwdriver.
If the screwdriver perforates the liner, or if the tapping does not
sound like metal hitting metal, the liner must be removed and
replaced (Fix 4—Relining).
REMEMBER: All appliances must be vented inside the liner.
Venting one appliance inside the liner and another appliance
outside the liner is not acceptable.
Next, use a flashlight and a small mirror to look up inside the liner.
B-vent must be supported so as to not come into direct contact
with the chimney walls or tile liner. If it is not, it can probably be
rehung so as to be acceptable. A thimble or fire stop may be
Flexible liners should be hung straight or nearly straight. If it is
spiraled in the chimney and in good condition, it should be
rehung. To do this, break the top seal. Pull up and cut off the
excess liner length and refit the top seal. Use caution when doing
this, since the cut edges of flexible liners may be sharp.