Item 1 of the exception is limit-
ed to concrete or masonry walls
and accepts filling the annular
space with concrete, grout or
mortar provided it is installed ei-
ther to the full thickness of the
wall or to the thickness required
to maintain the fire-resistance
rating. Figure 3.3 illustrates the
application of Item 1 of the ex-
ception. Code users could use
resources such as Table 721.1(2)
or other sources to determine
the required thickness for which
the opening is not to be filled for
its entire depth. As an example,
assume that a 6-inch concrete
wall of sand-lightweight con-
crete is to be penetrated.
Based on Item 4-1.1 of Table
721.1(2), a 2.7-inch thickness
would be required for a pene-
tration of a 1-hour wall while a
3.8-inch, 4.6-inch or 5.4 inch
thickness would be needed for a
2-hour, 3-hour, or 4-hour fire-re-
sistance ratings respectively.
Item 1 also places additional
restrictions that the penetrating
item may not exceed a nominal
6-inch diameter size and that
the size of the opening through
the original wall assembly may
not exceed 144 square inches.
This limits the size of the hole
through the wall to the equiv-
alent of a 12-inch by 12-inch
square opening or approximate-
ly a 13 ½ -inch-round opening.
PENETRATING ITEM
• 6″ MAX. NOMINAL
DIAMETER
OPENING THROUGH WALL
• 144 SQ. IN. MAXIMUM
MASONRY WALL
FILLED WITH CONCRETE,
GROUT OR MORTAR
• INSTALLED TO FULL THICKNESS
OF WALL, OR TO THICKNESS REQUIRED TO
MAINTAIN FIRE-RESISTANCE-RATING
CONCRETE WALL
(Fig 3.5)
61