Current through Register 1531, September 27, 2024
Parapets shall be provided on exterior
walls of buildings.
Exceptions: A parapet need not be provided on
an exterior wall where any of the following conditions
exist:
1. The wall is not required to
be fire-resistance rated in accordance with Table 602 because of fire
separation distance.
2.
The building has an area of not more than 1,000 square feet (93
m2) on any floor.
3. Walls that terminate at roofs of not less
than 2-hour fire-resistance-rated construction or where the roof, including the
deck or slab and supporting construction, is constructed entirely of
noncombustible materials.
4.
One-hour fire-resistance-rated exterior walls that terminate
at the underside of the roof sheathing, deck or slab, provided:
4.1. Where the roof/ceiling framing elements
are parallel to the walls, such framing and elements supporting such framing
shall not be of less than 1-hour fire-resistance-rated construction for a width
of 4 feet (1220 mm) for Groups R and U and 10 feet (3048 mm) for other
occupancies, measured from the interior side of the wall.
4.2. Where roof/ceiling framing elements are
not parallel to the wall, the entire span of such framing and elements
supporting such framing shall not be of less than 1-hour fire-resistance-rated
construction.
4.3. Openings in the
roof shall not be located within 5 feet (1524 mm) of the 1-hour
fire-resistance-rated exterior wall for Groups R and U and 10
feet (3048 mm) for other occupancies, measured from the interior side of the
wall.
4.4. The entire building
shall be provided with not less than a Class B roof covering.
5. In Groups R-2 and R-3 where the
entire building is provided with a Class C roof covering, the exterior
wall shall be permitted to terminate at the underside of the roof
sheathing or deck in Type III, IV and V construction, provided:
5.1. The roof sheathing or deck is
constructed of approved noncombustible materials or of
fire-retardant-treated wood for a distance of 4 feet (1220
mm); or
5.2. The roof is protected
with 0.625-inch (16 mm) Type X gypsum board directly beneath the underside of
the roof sheathing or deck, supported by a minimum of nominal 2-inch (51 mm)
ledgers attached to the sides of the roof framing members for a minimum
distance of 4 feet (1220 mm).
6. Where the wall is permitted to have at
least 25 percent of the exterior wall areas containing
unprotected openings based on fire separation distance as
determined in accordance with Section 705.8.
705.11.1
Parapet construction.
Parapets shall have the same fire-resistance rating as that
required for the supporting wall, and on any side adjacent to a roof surface,
shall have noncombustible faces for the uppermost 18 inches (457 mm), including
counterflashing and coping materials. The height of the parapet shall not be
less than 30 inches (762 mm) above the point where the roof surface and the
wall intersect. Where the roof slopes toward a parapet at a slope greater than
two units vertical in 12 units horizontal (16.7-percent slope), the parapet
shall extend to the same height as any portion of the roof within a
fire separation distance where protection of wall openings is
required, but in no case shall the height be less than 30 inches (762
mm).
