International Building Code Section 1604


International Building Code 1604.10

Wind and seismic detailing. Lateral-force-resisting
systems shall meet seismic detailing requirements and limitations
prescribed in this code and ASCE 7, excluding Chapter
14 and Appendix 11A, even when wind code prescribed load
effects are greater than seismic load effects.

International Building Code 1604.1

General. Building, structures and parts thereof shall be
designed and constructed in accordance with strength design,
load and resistance factor design, allowable stress design,
empirical design or conventional construction methods, as permitted
by the applicable material chapters.

International Building Code 1604.2

Strength. Buildings and other structures, and parts
thereof, shall be designed and constructed to support safely the
factored loads in load combinations defined in this code without
exceeding the appropriate strength limit states for the materials
of construction. Alternatively, buildings and other
structures, and parts thereof, shall be designed and constructed
to support safely the nominal loads in load combinations
defined in this code without exceeding the appropriate specified
allowable stresses for the materials of construction.
Loads and forces for occupancies or uses not covered in this
chapter shall be subject to the approval of the building official.

International Building Code 1604.3

Serviceability. Structural systems and members
thereof shall be designed to have adequate stiffness to limit
deflections and lateral drift. See Section 12.12.1 of ASCE 7 for
drift limits applicable to earthquake loading.

Deflections. The deflections of structural members
shall not exceed the more restrictive of the limitations
of Sections 1604.3.2 through 1604.3.5 or that permitted by
Table 1604.3.

Reinforced concrete. The deflection of reinforced
concrete structural members shall not exceed that
permitted by ACI 318.
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Steel. The deflection of steel structural members
shall not exceed that permitted by AISC 360, AISI-NAS,
AISI-General, AISI-Truss, ASCE 3, ASCE 8, SJI JG-1.1,
SJI K-1.1 or SJI LH/DLH-1.1, as applicable.

Masonry. The deflection of masonry structural
members shall not exceed that permitted by ACI 530/ASCE
5/TMS 402.

Aluminum. The deflection of aluminum structural
members shall not exceed that permitted by AA
ADM1.

Limits. Deflection of structural members over
span, l, shall not exceed that permitted by Table 1604.3.

International Building Code 1604.3.1

Deflections. The deflections of structural members
shall not exceed the more restrictive of the limitations
of Sections 1604.3.2 through 1604.3.5 or that permitted by
Table 1604.3.

International Building Code 1604.3.2

Reinforced concrete. The deflection of reinforced
concrete structural members shall not exceed that
permitted by ACI 318.
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International Building Code 1604.3.3

Steel. The deflection of steel structural members
shall not exceed that permitted by AISC 360, AISI-NAS,
AISI-General, AISI-Truss, ASCE 3, ASCE 8, SJI JG-1.1,
SJI K-1.1 or SJI LH/DLH-1.1, as applicable.

International Building Code 1604.3.4

Masonry. The deflection of masonry structural
members shall not exceed that permitted by ACI 530/ASCE
5/TMS 402.

International Building Code 1604.3.5

Aluminum. The deflection of aluminum structural
members shall not exceed that permitted by AA
ADM1.

International Building Code 1604.3.6

Limits. Deflection of structural members over
span, l, shall not exceed that permitted by Table 1604.3.

International Building Code 1604.4

Analysis. Load effects on structural members and their
connections shall be determined by methods of structural analysis
that take into account equilibrium, general stability, geometric
compatibility and both short- and long-term material
properties.
Members that tend to accumulate residual deformations
under repeated service loads shall have included in their analysis
the added eccentricities expected to occur during their service
life.
Any system or method of construction to be used shall be
based on a rational analysis in accordance with well-established
principles of mechanics. Such analysis shall result in a system
that provides a complete load path capable of transferring loads
from their point of origin to the load-resisting elements.
The total lateral force shall be distributed to the various vertical
elements of the lateral-force-resisting system in proportion
to their rigidities, considering the rigidity of the horizontal
bracing system or diaphragm. Rigid elements assumed not to
be a part of the lateral-force-resisting system are permitted to
be incorporated into buildings provided their effect on the
action of the system is considered and provided for in the
design. Except where diaphragms are flexible, or are permitted
to be analyzed as flexible, provisions shall be made for the
increased forces induced on resisting elements of the structural
system resulting from torsion due to eccentricity between the
center of application of the lateral forces and the center of rigidity
of the lateral-force-resisting system.
Every structure shall be designed to resist the overturning
effects caused by the lateral forces specified in this chapter. See
Section 1609 for wind loads, Section 1610 for lateral soil loads
and Section 1613 for earthquake loads.

International Building Code 1604.5

Occupancy category. Buildings shall be assigned an
occupancy category in accordance with Table 1604.5.

Multiple occupancies. Where a structure is occupied
by two or more occupancies not included in the same
occupancy category, the structure shall be assigned the classification
of the highest occupancy category corresponding
to the various occupancies. Where structures have two or
more portions that are structurally separated, each portion
shall be separately classified. Where a separated portion of a
structure provides required access to, required egress from
or shares life safety components with another portion having
a higher occupancy category, both portions shall be
assigned to the higher occupancy category.

International Building Code 1604.5.1

Multiple occupancies. Where a structure is occupied
by two or more occupancies not included in the same
occupancy category, the structure shall be assigned the classification
of the highest occupancy category corresponding
to the various occupancies. Where structures have two or
more portions that are structurally separated, each portion
shall be separately classified. Where a separated portion of a
structure provides required access to, required egress from
or shares life safety components with another portion having
a higher occupancy category, both portions shall be
assigned to the higher occupancy category.

International Building Code 1604.6

In-situ load tests. The building official is authorized to
require an engineering analysis or a load test, or both, of any
construction whenever there is reason to question the safety of
the construction for the intended occupancy. Engineering analysis
and load tests shall be conducted in accordance with Section
1713.

International Building Code 1604.7

Preconstruction load tests. Materials and methods of
construction that are not capable of being designed by
approved engineering analysis or that do not comply with the
applicable material design standards listed in Chapter 35, or
alternative test procedures in accordance with Section 1711,
shall be load tested in accordance with Section 1714.
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International Building Code 1604.8

Anchorage.

General. Anchorage of the roof to walls and columns,
and of walls and columns to foundations, shall be
provided to resist the uplift and sliding forces that result
from the application of the prescribed loads.

Concrete and masonry walls. Concrete and
masonry walls shall be anchored to floors, roofs and other
structural elements that provide lateral support for the wall.
Such anchorage shall provide a positive direct connection
capable of resisting the horizontal forces specified in this
chapter but not less than a minimum strength design horizontal
force of 280 plf (4.10 kN/m) of wall, substituted for
“E” in the load combinations of Section 1605.2 or 1605.3.
Walls shall be designed to resist bending between anchors
where the anchor spacing exceeds 4 feet (1219 mm).
Required anchors in masonrywalls of hollowunits or cavity
walls shall be embedded in a reinforced grouted structural
element of the wall. See Sections 1609 for wind design
requirements and see Section 1613 for earthquake design
requirements.

Decks. Where supported by attachment to an exterior
wall, decks shall be positively anchored to the primary structure
and designed for both vertical and lateral loads as applicable.
Such attachment shall not be accomplished by the use of
toenails or nails subject to withdrawal.Where positive connection
to the primary building structure cannot be verified during
inspection, decks shall be self-supporting. For deckswith cantilevered
framing members, connections to exterior walls or
other framing members shall be designed and constructed to
resist uplift resulting from the full live load specified in Table
1607.1 acting on the cantilevered portion of the deck.

International Building Code 1604.8.1

General. Anchorage of the roof to walls and columns,
and of walls and columns to foundations, shall be
provided to resist the uplift and sliding forces that result
from the application of the prescribed loads.

International Building Code 1604.8.2

Concrete and masonry walls. Concrete and
masonry walls shall be anchored to floors, roofs and other
structural elements that provide lateral support for the wall.
Such anchorage shall provide a positive direct connection
capable of resisting the horizontal forces specified in this
chapter but not less than a minimum strength design horizontal
force of 280 plf (4.10 kN/m) of wall, substituted for
“E” in the load combinations of Section 1605.2 or 1605.3.
Walls shall be designed to resist bending between anchors
where the anchor spacing exceeds 4 feet (1219 mm).
Required anchors in masonrywalls of hollowunits or cavity
walls shall be embedded in a reinforced grouted structural
element of the wall. See Sections 1609 for wind design
requirements and see Section 1613 for earthquake design
requirements.

International Building Code 1604.8.3

Decks. Where supported by attachment to an exterior
wall, decks shall be positively anchored to the primary structure
and designed for both vertical and lateral loads as applicable.
Such attachment shall not be accomplished by the use of
toenails or nails subject to withdrawal.Where positive connection
to the primary building structure cannot be verified during
inspection, decks shall be self-supporting. For deckswith cantilevered
framing members, connections to exterior walls or
other framing members shall be designed and constructed to
resist uplift resulting from the full live load specified in Table
1607.1 acting on the cantilevered portion of the deck.

International Building Code 1604.9

Counteracting structural actions. Structural members,
systems, components and cladding shall be designed to
resist forces due to earthquake and wind, with consideration of
overturning, sliding, and uplift. Continuous load paths shall be
provided for transmitting these forces to the foundation. Where
sliding is used to isolate the elements, the effects of friction
between sliding elements shall be included as a force.