International Building Code Section 2304


International Building Code 2304.10

Heavy timber construction.

Columns. Columns shall be continuous or superimposed
throughout all stories by means of reinforced concrete
or metal caps with brackets, or shall be connected by
properly designed steel or iron caps, with pintles and base
plates, or by timber splice plates affixed to the columns by
metal connectors housed within the contact faces, or by
other approved methods.

Column connections. Girders and beams
shall be closely fitted around columns and adjoining
ends shall be cross tied to each other, or intertied by caps
or ties, to transfer horizontal loads across joints. Wood
bolsters shall not be placed on tops of columns unless the
columns support roof loads only.

Floor framing. Approved wall plate boxes or
hangers shall be provided where wood beams, girders or
trusses rest on masonry or concretewalls. Where intermediate
beams are used to support a floor, they shall rest on top of
girders, or shall be supported by ledgers or blocks securely
fastened to the sides of the girders, or they shall be supported
by an approved metal hanger into which the ends of
the beams shall be closely fitted.

Roof framing. Every roof girder and at least
every alternate roof beam shall be anchored to its supporting
member; and every monitor and every sawtooth construction
shall be anchored to the main roof construction. Such
anchors shall consist of steel or iron bolts of sufficient
strength to resist vertical uplift of the roof.
430 2006 INTERNATIONAL BUILDING CODE
WOOD
2006 INTERNATIONAL BUILDING CODE 431
WOOD

Floor decks. Floor decks and covering shall not
extend closer than 1/2 inch (12.7 mm) to walls. Such 1/2-inch
(12.7 mm) spaces shall be covered by a molding fastened to
the wall either above or below the floor and arranged such
that the molding will not obstruct the expansion or contraction
movements of the floor. Corbeling of masonry walls
under floors is permitted in place of such molding.

Roof decks. Where supported by a wall, roof
decks shall be anchored to walls to resist uplift forces determined
in accordance with Chapter 16. Such anchors shall
consist of steel or iron bolts of sufficient strength to resist
vertical uplift of the roof.

International Building Code 2304.1

General. The provisions of this section apply to design
methods specified in Section 2301.2.

International Building Code 2304.10.1

Columns. Columns shall be continuous or superimposed
throughout all stories by means of reinforced concrete
or metal caps with brackets, or shall be connected by
properly designed steel or iron caps, with pintles and base
plates, or by timber splice plates affixed to the columns by
metal connectors housed within the contact faces, or by
other approved methods.

Column connections. Girders and beams
shall be closely fitted around columns and adjoining
ends shall be cross tied to each other, or intertied by caps
or ties, to transfer horizontal loads across joints. Wood
bolsters shall not be placed on tops of columns unless the
columns support roof loads only.

International Building Code 2304.10.1.1

Column connections. Girders and beams
shall be closely fitted around columns and adjoining
ends shall be cross tied to each other, or intertied by caps
or ties, to transfer horizontal loads across joints. Wood
bolsters shall not be placed on tops of columns unless the
columns support roof loads only.

International Building Code 2304.10.2

Floor framing. Approved wall plate boxes or
hangers shall be provided where wood beams, girders or
trusses rest on masonry or concretewalls. Where intermediate
beams are used to support a floor, they shall rest on top of
girders, or shall be supported by ledgers or blocks securely
fastened to the sides of the girders, or they shall be supported
by an approved metal hanger into which the ends of
the beams shall be closely fitted.

International Building Code 2304.10.3

Roof framing. Every roof girder and at least
every alternate roof beam shall be anchored to its supporting
member; and every monitor and every sawtooth construction
shall be anchored to the main roof construction. Such
anchors shall consist of steel or iron bolts of sufficient
strength to resist vertical uplift of the roof.
430 2006 INTERNATIONAL BUILDING CODE
WOOD
2006 INTERNATIONAL BUILDING CODE 431
WOOD

International Building Code 2304.10.4

Floor decks. Floor decks and covering shall not
extend closer than 1/2 inch (12.7 mm) to walls. Such 1/2-inch
(12.7 mm) spaces shall be covered by a molding fastened to
the wall either above or below the floor and arranged such
that the molding will not obstruct the expansion or contraction
movements of the floor. Corbeling of masonry walls
under floors is permitted in place of such molding.

International Building Code 2304.10.5

Roof decks. Where supported by a wall, roof
decks shall be anchored to walls to resist uplift forces determined
in accordance with Chapter 16. Such anchors shall
consist of steel or iron bolts of sufficient strength to resist
vertical uplift of the roof.

International Building Code 2304.11

Protection against decay and termites.

General. Where required by this section, protection
from decay and termites shall be provided by the use of
naturally durable or preservative-treated wood.

Wood used above ground. Wood used above
ground in the locations specified in Sections 2304.11.2.1
through 2304.11.2.7, 2304.11.3 and 2304.11.5 shall be naturally
durable wood or preservative-treated wood using
water-borne preservatives, in accordance with AWPA U1
(Commodity Specifications A or F) for above-ground use.

Joists, girders and subfloor. Where wood
joists or the bottom of a wood structural floor without
joists are closer than 18 inches (457 mm), or wood girders
are closer than 12 inches (305 mm) to the exposed
ground in crawl spaces or unexcavated areas located
within the perimeter of the building foundation, the floor
assembly (including posts, girders, joists and subfloor)
shall be of naturally durable or preservative-treated
wood.

Wood supported by exterior foundation
walls. Wood framing members, including wood sheathing,
that rest on exterior foundation walls and are less
than 8 inches (203 mm) from exposed earth shall be of
naturally durable or preservative-treated wood.

Exterior walls below grade. Wood framing
members and furring strips attached directly to the
interior of exterior masonry or concrete walls below
grade shall be of approved naturally durable or preservative-
treated wood.

Sleepers and sills. Sleepers and sills on a
concrete or masonry slab that is in direct contact with
earth shall be of naturally durable or preservative-treated
wood.

Girder ends. The ends of wood girders
entering exterior masonry or concrete walls shall be provided
with a 1/2-inch (12.7 mm) air space on top, sides
and end, unless naturally durable or preservative-treated
wood is used.

Wood siding. Clearance between wood siding
and earth on the exterior of a building shall not be less
than 6 inches (152 mm) except where siding, sheathing
and wall framing are of naturally durable or preservative-
treated wood.

Posts or columns. Posts or columns supporting
permanent structures and supported by a concrete
or masonry slab or footing that is in direct contact
with the earth shall be of naturally durable or preservative-
treated wood.
Exceptions:
1. Posts or columns that are either exposed to the
weather or located in basements or cellars, supported
by concrete piers or metal pedestals projected
at least 1 inch (25 mm) above the slab or
deck and 6 inches (152 mm) above exposed
earth, and are separated therefrom by an impervious
moisture barrier.
2. Posts or columns in enclosed crawl spaces or
unexcavated areas locatedwithin the periphery of
the building, supported by a concrete pier or metal
pedestal at a height greater than 8 inches (203
mm) from exposed ground, and are separated
therefrom by an impervious moisture barrier.

Laminated timbers. The portions of glued-laminated
timbers that form the structural supports of a building
or other structure and are exposed to weather and not fully
protected from moisture by a roof, eave or similar covering
shall be pressure treated with preservative or be manufactured
from naturally durable or preservative-treatedwood.

Wood in contactwith the ground or freshwater.
Wood used in contact with the ground (exposed earth) in the
locations specified in Sections 2304.11.4.1 and 2304.11.4.2
shall be naturally durable (species for both decay and termite
resistance) or preservative treated using water-borne preservatives
in accordance with AWPA U1 (Commodity Specifications
A or F) for soil or fresh water use.
Exception: Untreated wood is permitted where such
wood is continuously and entirely below the
ground-water level or submerged in fresh water.

Posts or columns. Posts and columns supporting
permanent structures that are embedded in concrete
that is in direct contact with the earth, embedded in
concrete that is exposed to the weather or in direct contact
with the earth shall be of preservative-treatedwood.

Wood structural members. Wood structural
members that support moisture-permeable floors or
roofs that are exposed to the weather, such as concrete or
masonry slabs, shall be of naturally durable or preservative-
treated wood unless separated from such floors or
roofs by an impervious moisture barrier.

Supporting member for permanent appurtenances.
Naturally durable or preservative-treated wood
shall be utilized for those portions of wood members that
form the structural supports of buildings, balconies, porches
or similar permanent building appurtenances where such
members are exposed to the weather without adequate protection
from a roof, eave, overhang or other covering to pre-
434 2006 INTERNATIONAL BUILDING CODE
WOOD
vent moisture or water accumulation on the surface or at
joints between members.
Exception: When a building is located in a geographical
region where experience has demonstrated that climatic
conditions preclude the need to use durable materials
where the structure is exposed to the weather.

Termite protection. In geographical areas
where hazard of termite damage is known to be very heavy,
wood floor framing shall be of naturally durable species
(termite resistant) or preservative treated in accordance with
AWPA U1 for the species, product preservative and end use
or provided with approved methods of termite protection.

Wood used in retaining walls and cribs.Wood
installed in retaining or crib walls shall be preservative
treated in accordance with AWPA U1 (Commodity Specifications
A or F) for soil and fresh water use.

Attic ventilation. For attic ventilation, see Section
1203.2.

Under-floor ventilation (crawl space). For
under-floor ventilation (crawl space), see Section 1203.3.

International Building Code 2304.11.1

General. Where required by this section, protection
from decay and termites shall be provided by the use of
naturally durable or preservative-treated wood.

International Building Code 2304.11.2

Wood used above ground. Wood used above
ground in the locations specified in Sections 2304.11.2.1
through 2304.11.2.7, 2304.11.3 and 2304.11.5 shall be naturally
durable wood or preservative-treated wood using
water-borne preservatives, in accordance with AWPA U1
(Commodity Specifications A or F) for above-ground use.

Joists, girders and subfloor. Where wood
joists or the bottom of a wood structural floor without
joists are closer than 18 inches (457 mm), or wood girders
are closer than 12 inches (305 mm) to the exposed
ground in crawl spaces or unexcavated areas located
within the perimeter of the building foundation, the floor
assembly (including posts, girders, joists and subfloor)
shall be of naturally durable or preservative-treated
wood.

Wood supported by exterior foundation
walls. Wood framing members, including wood sheathing,
that rest on exterior foundation walls and are less
than 8 inches (203 mm) from exposed earth shall be of
naturally durable or preservative-treated wood.

Exterior walls below grade. Wood framing
members and furring strips attached directly to the
interior of exterior masonry or concrete walls below
grade shall be of approved naturally durable or preservative-
treated wood.

Sleepers and sills. Sleepers and sills on a
concrete or masonry slab that is in direct contact with
earth shall be of naturally durable or preservative-treated
wood.

Girder ends. The ends of wood girders
entering exterior masonry or concrete walls shall be provided
with a 1/2-inch (12.7 mm) air space on top, sides
and end, unless naturally durable or preservative-treated
wood is used.

Wood siding. Clearance between wood siding
and earth on the exterior of a building shall not be less
than 6 inches (152 mm) except where siding, sheathing
and wall framing are of naturally durable or preservative-
treated wood.

Posts or columns. Posts or columns supporting
permanent structures and supported by a concrete
or masonry slab or footing that is in direct contact
with the earth shall be of naturally durable or preservative-
treated wood.
Exceptions:
1. Posts or columns that are either exposed to the
weather or located in basements or cellars, supported
by concrete piers or metal pedestals projected
at least 1 inch (25 mm) above the slab or
deck and 6 inches (152 mm) above exposed
earth, and are separated therefrom by an impervious
moisture barrier.
2. Posts or columns in enclosed crawl spaces or
unexcavated areas locatedwithin the periphery of
the building, supported by a concrete pier or metal
pedestal at a height greater than 8 inches (203
mm) from exposed ground, and are separated
therefrom by an impervious moisture barrier.

International Building Code 2304.11.2.1

Joists, girders and subfloor. Where wood
joists or the bottom of a wood structural floor without
joists are closer than 18 inches (457 mm), or wood girders
are closer than 12 inches (305 mm) to the exposed
ground in crawl spaces or unexcavated areas located
within the perimeter of the building foundation, the floor
assembly (including posts, girders, joists and subfloor)
shall be of naturally durable or preservative-treated
wood.

International Building Code 2304.11.2.2

Wood supported by exterior foundation
walls. Wood framing members, including wood sheathing,
that rest on exterior foundation walls and are less
than 8 inches (203 mm) from exposed earth shall be of
naturally durable or preservative-treated wood.

International Building Code 2304.11.2.3

Exterior walls below grade. Wood framing
members and furring strips attached directly to the
interior of exterior masonry or concrete walls below
grade shall be of approved naturally durable or preservative-
treated wood.

International Building Code 2304.11.2.4

Sleepers and sills. Sleepers and sills on a
concrete or masonry slab that is in direct contact with
earth shall be of naturally durable or preservative-treated
wood.

International Building Code 2304.11.2.5

Girder ends. The ends of wood girders
entering exterior masonry or concrete walls shall be provided
with a 1/2-inch (12.7 mm) air space on top, sides
and end, unless naturally durable or preservative-treated
wood is used.

International Building Code 2304.11.2.6

Wood siding. Clearance between wood siding
and earth on the exterior of a building shall not be less
than 6 inches (152 mm) except where siding, sheathing
and wall framing are of naturally durable or preservative-
treated wood.

International Building Code 2304.11.2.7

Posts or columns. Posts or columns supporting
permanent structures and supported by a concrete
or masonry slab or footing that is in direct contact
with the earth shall be of naturally durable or preservative-
treated wood.
Exceptions:
1. Posts or columns that are either exposed to the
weather or located in basements or cellars, supported
by concrete piers or metal pedestals projected
at least 1 inch (25 mm) above the slab or
deck and 6 inches (152 mm) above exposed
earth, and are separated therefrom by an impervious
moisture barrier.
2. Posts or columns in enclosed crawl spaces or
unexcavated areas locatedwithin the periphery of
the building, supported by a concrete pier or metal
pedestal at a height greater than 8 inches (203
mm) from exposed ground, and are separated
therefrom by an impervious moisture barrier.

International Building Code 2304.11.3

Laminated timbers. The portions of glued-laminated
timbers that form the structural supports of a building
or other structure and are exposed to weather and not fully
protected from moisture by a roof, eave or similar covering
shall be pressure treated with preservative or be manufactured
from naturally durable or preservative-treatedwood.

International Building Code 2304.11.4

Wood in contactwith the ground or freshwater.
Wood used in contact with the ground (exposed earth) in the
locations specified in Sections 2304.11.4.1 and 2304.11.4.2
shall be naturally durable (species for both decay and termite
resistance) or preservative treated using water-borne preservatives
in accordance with AWPA U1 (Commodity Specifications
A or F) for soil or fresh water use.
Exception: Untreated wood is permitted where such
wood is continuously and entirely below the
ground-water level or submerged in fresh water.

Posts or columns. Posts and columns supporting
permanent structures that are embedded in concrete
that is in direct contact with the earth, embedded in
concrete that is exposed to the weather or in direct contact
with the earth shall be of preservative-treatedwood.

Wood structural members. Wood structural
members that support moisture-permeable floors or
roofs that are exposed to the weather, such as concrete or
masonry slabs, shall be of naturally durable or preservative-
treated wood unless separated from such floors or
roofs by an impervious moisture barrier.

International Building Code 2304.11.4.1

Posts or columns. Posts and columns supporting
permanent structures that are embedded in concrete
that is in direct contact with the earth, embedded in
concrete that is exposed to the weather or in direct contact
with the earth shall be of preservative-treatedwood.

International Building Code 2304.11.4.2

Wood structural members. Wood structural
members that support moisture-permeable floors or
roofs that are exposed to the weather, such as concrete or
masonry slabs, shall be of naturally durable or preservative-
treated wood unless separated from such floors or
roofs by an impervious moisture barrier.

International Building Code 2304.11.5

Supporting member for permanent appurtenances.
Naturally durable or preservative-treated wood
shall be utilized for those portions of wood members that
form the structural supports of buildings, balconies, porches
or similar permanent building appurtenances where such
members are exposed to the weather without adequate protection
from a roof, eave, overhang or other covering to pre-
434 2006 INTERNATIONAL BUILDING CODE
WOOD
vent moisture or water accumulation on the surface or at
joints between members.
Exception: When a building is located in a geographical
region where experience has demonstrated that climatic
conditions preclude the need to use durable materials
where the structure is exposed to the weather.

International Building Code 2304.11.6

Termite protection. In geographical areas
where hazard of termite damage is known to be very heavy,
wood floor framing shall be of naturally durable species
(termite resistant) or preservative treated in accordance with
AWPA U1 for the species, product preservative and end use
or provided with approved methods of termite protection.

International Building Code 2304.11.7

Wood used in retaining walls and cribs.Wood
installed in retaining or crib walls shall be preservative
treated in accordance with AWPA U1 (Commodity Specifications
A or F) for soil and fresh water use.

International Building Code 2304.11.8

Attic ventilation. For attic ventilation, see Section
1203.2.

International Building Code 2304.11.9

Under-floor ventilation (crawl space). For
under-floor ventilation (crawl space), see Section 1203.3.

International Building Code 2304.12

Long-term loading.Wood members supporting concrete,
masonry or similar materials shall be checked for the
effects of long-term loading using the provisions of the
AF&PA NDS. The total deflection, including the effects of
long-term loading, shall be limited in accordance with Section
1604.3.1 for these supported materials.
Exception: Horizontalwood members supporting masonry
or concrete nonstructural floor or roof surfacing not more
than 4 inches (102 mm) thick need not be checked for
long-term loading.

International Building Code 2304.2

Size of structural members. Computations to determine
the required sizes of members shall be based on the net
dimensions (actual sizes) and not nominal sizes.

International Building Code 2304.3

Wall framing. The framing of exterior and interior
walls shall be in accordance with the provisions specified in
Section 2308 unless a specific design is furnished.

Bottom plates. Studs shall have full bearing on a
2-inch-thick (actual 11/2-inch, 38 mm) or larger plate or sill
having a width at least equal to the width of the studs.

Framing over openings. Headers, double joists,
trusses or other approved assemblies that are of adequate
size to transfer loads to the vertical members shall be provided
over windowand door openings in load-bearingwalls
and partitions.

Shrinkage. Wood walls and bearing partitions
shall not support more than two floors and a roof unless an
analysis satisfactory to the building official shows that
shrinkage of the wood framing will not have adverse effects
on the structure or any plumbing, electrical or mechanical
systems, or other equipment installed therein due to excessive
shrinkage or differential movements caused by shrinkage.
The analysis shall also show that the roof drainage
system and the foregoing systems or equipment will not be
adversely affected or, as an alternate, such systems shall be
designed to accommodate the differential shrinkage or
movements.

International Building Code 2304.3.1

Bottom plates. Studs shall have full bearing on a
2-inch-thick (actual 11/2-inch, 38 mm) or larger plate or sill
having a width at least equal to the width of the studs.

International Building Code 2304.3.2

Framing over openings. Headers, double joists,
trusses or other approved assemblies that are of adequate
size to transfer loads to the vertical members shall be provided
over windowand door openings in load-bearingwalls
and partitions.

International Building Code 2304.3.3

Shrinkage. Wood walls and bearing partitions
shall not support more than two floors and a roof unless an
analysis satisfactory to the building official shows that
shrinkage of the wood framing will not have adverse effects
on the structure or any plumbing, electrical or mechanical
systems, or other equipment installed therein due to excessive
shrinkage or differential movements caused by shrinkage.
The analysis shall also show that the roof drainage
system and the foregoing systems or equipment will not be
adversely affected or, as an alternate, such systems shall be
designed to accommodate the differential shrinkage or
movements.

International Building Code 2304.4

Floor and roof framing. The framing of wood-joisted
floors and wood framed roofs shall be in accordance with the
provisions specified in Section 2308 unless a specific design is
furnished.

International Building Code 2304.5

Framing around flues and chimneys. Combustible
framing shall be a minimum of 2 inches (51 mm), but shall not
be less than the distance specified in Sections 2111 and 2113
and the International Mechanical Code, from flues, chimneys
and fireplaces, and 6 inches (152 mm) away from flue openings.

International Building Code 2304.6

Wall sheathing. Except as provided for in Section 1405
for weatherboarding or where stucco construction that complies
with Section 2510 is installed, enclosed buildings shall be
sheathed with one of the materials of the nominal thickness
specified in Table 2304.6 or any other approved material of
equivalent strength or durability.

Wood structural panel sheathing. Where wood
structural panel sheathing is used as the exposed finish on
the exterior of outside walls, it shall have an exterior exposure
durability classification. Where wood structural panel
sheathing is used on the exterior of outside walls but not as
the exposed finish, it shall be of a type manufactured with
exterior glue (Exposure 1 or Exterior). Where wood structural
panel sheathing is used elsewhere, it shall be of a type
manufactured with intermediate or exterior glue.

Interior paneling. Softwood wood structural
panels used for interior paneling shall conform with the
provisions of Chapter 8 and shall be installed in accordance
with Table 2304.9.1. Panels shall comply with DOC
PS 1 or PS 2. Prefinished hardboard paneling shall meet
the requirements of AHA A135.5. Hardwood plywood
shall conform to HPVA HP-1.

International Building Code 2304.6.1

Wood structural panel sheathing. Where wood
structural panel sheathing is used as the exposed finish on
the exterior of outside walls, it shall have an exterior exposure
durability classification. Where wood structural panel
sheathing is used on the exterior of outside walls but not as
the exposed finish, it shall be of a type manufactured with
exterior glue (Exposure 1 or Exterior). Where wood structural
panel sheathing is used elsewhere, it shall be of a type
manufactured with intermediate or exterior glue.

International Building Code 2304.6.2

Interior paneling. Softwood wood structural
panels used for interior paneling shall conform with the
provisions of Chapter 8 and shall be installed in accordance
with Table 2304.9.1. Panels shall comply with DOC
PS 1 or PS 2. Prefinished hardboard paneling shall meet
the requirements of AHA A135.5. Hardwood plywood
shall conform to HPVA HP-1.

International Building Code 2304.7

Floor and roof sheathing.

Structural floor sheathing. Structural floor
sheathing shall be designed in accordance with the general
provisions of this code and the special provisions in this section.
Floor sheathing conforming to the provisions of Table
2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(4) shall be
deemed to meet the requirements of this section.

Structural roof sheathing. Structural roof sheathing
shall be designed in accordance with the general provisions
of this code and the special provisions in this section.
Roof sheathing conforming to the provisions of Table
2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(5) shall be
deemed to meet the requirements of this section.Wood structural
panel roof sheathing shall be bonded by exterior glue.
426 2006 INTERNATIONAL BUILDING CODE
WOOD

International Building Code 2304.7.1

Structural floor sheathing. Structural floor
sheathing shall be designed in accordance with the general
provisions of this code and the special provisions in this section.
Floor sheathing conforming to the provisions of Table
2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(4) shall be
deemed to meet the requirements of this section.

International Building Code 2304.7.2

Structural roof sheathing. Structural roof sheathing
shall be designed in accordance with the general provisions
of this code and the special provisions in this section.
Roof sheathing conforming to the provisions of Table
2304.7(1), 2304.7(2), 2304.7(3) or 2304.7(5) shall be
deemed to meet the requirements of this section.Wood structural
panel roof sheathing shall be bonded by exterior glue.
426 2006 INTERNATIONAL BUILDING CODE
WOOD

International Building Code 2304.8

Lumber decking.

General. Lumber decking shall be designed and
installed in accordance with the general provisions of this
code and the provisions of this section. Each piece shall be
square-end trimmed. When random lengths are furnished,
each piece shall be square-end trimmed across the face so
that at least 90 percent of the pieces will be within 0.5
degrees (0.00873 rad) of square. The ends of the pieces shall
be permitted to be beveled up to 2 degrees (0.0349 rad) from
vertical with the exposed face of the piece slightly longer
than the back of the piece.Tongue-and-groove decking shall
be installed with the tongues up on sloped or pitched roofs
with pattern faces down.

Layup patterns. Lumber decking is permitted to
be laid up following one of five standard patterns as defined
in Sections 2304.8.2.1 through 2304.8.2.5. Other patterns
are permitted to be used if justified by engineering analysis.

Simple span pattern. All pieces shall be supported
by two supports.

Two-span continuous pattern. All pieces
shall be supported by three supports, and all end joints
shall occur in line on every other support. Supporting
members shall be designed to accommodate the load
redistribution caused by this pattern.

Combination simple and two-span continuous
pattern. Courses in end spans shall be alternating
simple span and two span continuous. End joints are
staggered in adjacent courses and occur only over supports.

Cantilevered pieces intermixed pattern.
The decking shall cover a minimum of three spans.
Pieces in the starter course and every third course shall be
simple span. Pieces in other courses shall be cantilevered
over the supports with end joints at alternate quarter or
third points of the spans, and each piece shall bear on at
least one support.

Controlled random pattern. The decking
shall cover a minimum of three spans. End joints within 6
inches (152 mm) of being in line in either direction shall
be separated by at least two intervening courses. In the
end bays each piece shall bear on at least one support.
Where an end joint occurs in an end bay, the next piece in
the same course shall continue over the first inner support
for at least 24 inches (610 mm). The details of the
controlled random pattern shall be as described for each
decking material in Section 2304.8.3.3, 2304.8.4.3 or
2304.8.5.3.
For cantilevered spans with the controlled random pattern,
special considerations shall be made when the overhang
exceeds 18 inches (457 mm), 24 inches (610 mm)
or 36 inches (914 mm) for 2-inch (51 mm), 3-inch (76
mm) or 4-inch (102 mm) nominal thickness decking,
respectively. The maximum cantilevered length for the
controlled random pattern shall be 30 percent of the
length of the first adjacent interior span. For cantilever
overhangs within these limits, a structural fascia shall be
fastened to each decking piece to maintain a continuous,
straight roof line. There shall be no end joints in the cantilevered
portion or within one-half of the first adjacent
interior span.

Mechanically laminated decking.

General. Mechanically laminated decking
consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the
supports.

2006 INTERNATIONAL BUILDING CODE 427
WOOD

Nailing. The length of nails connecting laminations
shall not be less than two and one-half times the
net thickness of each lamination. Where deck supports
are 48 inches (1219 mm) on center (o.c.) or less, side
nails shall be spaced not more than 30 inches (762 mm)
o.c. alternately near top and bottom edges, and staggered
one-third of the spacing in adjacent laminations. Where
supports are spaced more than 48 inches (1219 mm) o.c.,
side nails shall be spaced not more than 18 inches (457
mm) o.c. alternately near top and bottom edges and staggered
one-third of the spacing in adjacent laminations.
Two side nails shall be used at each end of butt-jointed
pieces.
Laminations shall be toenailed to supports with 20d or
larger common nails. Where the supports are 48 inches
(1219 mm) o.c. or less, alternate laminations shall be
toenailed to alternate supports; where supports are
spaced more than 48 inches (1219 mm) o.c., alternate
laminations shall be toenailed to every support.

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.
428 2006 INTERNATIONAL BUILDING CODE
WOOD

Two-inch sawn tongue-and-groove decking.

General. Two-inch (51 mm) decking shall
have a maximum moisture content of 15 percent. Decking
shall be machined with a single tongue-and-groove
pattern. Each deck piece shall be nailed to each support
as required.

Nailing. Each piece of decking shall be
toenailed at each support with one 16d common nail
through the tongue and face-nailed with one 16d common
nail.

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.

Three- and 4-inch sawn tongue-and-groove
decking.

General. Three-inch (76 mm) and 4-inch
(102 mm) decking shall have a maximum moisture content
of 19 percent. Decking shall be machined with a
double tongue-and-groove pattern. Deck pieces shall be
interconnected and fastened to the supports as required.

Nailing. Each piece shall be toenailed at each
support with one 40d common nail and face-nailed with
one 60d common nail. Courses shall be spiked to each
other with 8-inch (203 mm) spikes at intervals not to
exceed 30 inches (762 mm) through predrilled edge
holes penetrating to a depth of approximately 4 inches
(102 mm) and with one spike at a distance not exceeding
10 inches (254 mm) from the end of each piece.

Controlled random pattern. There shall be
a minimum distance of 48 inches (1219 mm) between
end joints in adjacent courses. Pieces not bearing over a
support are permitted to occur in interior bays, provided
the adjacent pieces in the same course continue over the
support for at least 24 inches (610 mm). This condition
shall not occur more than once in every six courses in
each interior bay.

International Building Code 2304.8.1

General. Lumber decking shall be designed and
installed in accordance with the general provisions of this
code and the provisions of this section. Each piece shall be
square-end trimmed. When random lengths are furnished,
each piece shall be square-end trimmed across the face so
that at least 90 percent of the pieces will be within 0.5
degrees (0.00873 rad) of square. The ends of the pieces shall
be permitted to be beveled up to 2 degrees (0.0349 rad) from
vertical with the exposed face of the piece slightly longer
than the back of the piece.Tongue-and-groove decking shall
be installed with the tongues up on sloped or pitched roofs
with pattern faces down.

International Building Code 2304.8.2

Layup patterns. Lumber decking is permitted to
be laid up following one of five standard patterns as defined
in Sections 2304.8.2.1 through 2304.8.2.5. Other patterns
are permitted to be used if justified by engineering analysis.

Simple span pattern. All pieces shall be supported
by two supports.

Two-span continuous pattern. All pieces
shall be supported by three supports, and all end joints
shall occur in line on every other support. Supporting
members shall be designed to accommodate the load
redistribution caused by this pattern.

Combination simple and two-span continuous
pattern. Courses in end spans shall be alternating
simple span and two span continuous. End joints are
staggered in adjacent courses and occur only over supports.

Cantilevered pieces intermixed pattern.
The decking shall cover a minimum of three spans.
Pieces in the starter course and every third course shall be
simple span. Pieces in other courses shall be cantilevered
over the supports with end joints at alternate quarter or
third points of the spans, and each piece shall bear on at
least one support.

Controlled random pattern. The decking
shall cover a minimum of three spans. End joints within 6
inches (152 mm) of being in line in either direction shall
be separated by at least two intervening courses. In the
end bays each piece shall bear on at least one support.
Where an end joint occurs in an end bay, the next piece in
the same course shall continue over the first inner support
for at least 24 inches (610 mm). The details of the
controlled random pattern shall be as described for each
decking material in Section 2304.8.3.3, 2304.8.4.3 or
2304.8.5.3.
For cantilevered spans with the controlled random pattern,
special considerations shall be made when the overhang
exceeds 18 inches (457 mm), 24 inches (610 mm)
or 36 inches (914 mm) for 2-inch (51 mm), 3-inch (76
mm) or 4-inch (102 mm) nominal thickness decking,
respectively. The maximum cantilevered length for the
controlled random pattern shall be 30 percent of the
length of the first adjacent interior span. For cantilever
overhangs within these limits, a structural fascia shall be
fastened to each decking piece to maintain a continuous,
straight roof line. There shall be no end joints in the cantilevered
portion or within one-half of the first adjacent
interior span.

International Building Code 2304.8.2.1

Simple span pattern. All pieces shall be supported
by two supports.

International Building Code 2304.8.2.2

Two-span continuous pattern. All pieces
shall be supported by three supports, and all end joints
shall occur in line on every other support. Supporting
members shall be designed to accommodate the load
redistribution caused by this pattern.

International Building Code 2304.8.2.3

Combination simple and two-span continuous
pattern. Courses in end spans shall be alternating
simple span and two span continuous. End joints are
staggered in adjacent courses and occur only over supports.

International Building Code 2304.8.2.4

Cantilevered pieces intermixed pattern.
The decking shall cover a minimum of three spans.
Pieces in the starter course and every third course shall be
simple span. Pieces in other courses shall be cantilevered
over the supports with end joints at alternate quarter or
third points of the spans, and each piece shall bear on at
least one support.

International Building Code 2304.8.2.5

Controlled random pattern. The decking
shall cover a minimum of three spans. End joints within 6
inches (152 mm) of being in line in either direction shall
be separated by at least two intervening courses. In the
end bays each piece shall bear on at least one support.
Where an end joint occurs in an end bay, the next piece in
the same course shall continue over the first inner support
for at least 24 inches (610 mm). The details of the
controlled random pattern shall be as described for each
decking material in Section 2304.8.3.3, 2304.8.4.3 or
2304.8.5.3.
For cantilevered spans with the controlled random pattern,
special considerations shall be made when the overhang
exceeds 18 inches (457 mm), 24 inches (610 mm)
or 36 inches (914 mm) for 2-inch (51 mm), 3-inch (76
mm) or 4-inch (102 mm) nominal thickness decking,
respectively. The maximum cantilevered length for the
controlled random pattern shall be 30 percent of the
length of the first adjacent interior span. For cantilever
overhangs within these limits, a structural fascia shall be
fastened to each decking piece to maintain a continuous,
straight roof line. There shall be no end joints in the cantilevered
portion or within one-half of the first adjacent
interior span.

International Building Code 2304.8.3

Mechanically laminated decking.

General. Mechanically laminated decking
consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the
supports.

2006 INTERNATIONAL BUILDING CODE 427
WOOD

Nailing. The length of nails connecting laminations
shall not be less than two and one-half times the
net thickness of each lamination. Where deck supports
are 48 inches (1219 mm) on center (o.c.) or less, side
nails shall be spaced not more than 30 inches (762 mm)
o.c. alternately near top and bottom edges, and staggered
one-third of the spacing in adjacent laminations. Where
supports are spaced more than 48 inches (1219 mm) o.c.,
side nails shall be spaced not more than 18 inches (457
mm) o.c. alternately near top and bottom edges and staggered
one-third of the spacing in adjacent laminations.
Two side nails shall be used at each end of butt-jointed
pieces.
Laminations shall be toenailed to supports with 20d or
larger common nails. Where the supports are 48 inches
(1219 mm) o.c. or less, alternate laminations shall be
toenailed to alternate supports; where supports are
spaced more than 48 inches (1219 mm) o.c., alternate
laminations shall be toenailed to every support.

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.
428 2006 INTERNATIONAL BUILDING CODE
WOOD

International Building Code 2304.8.3.1

General. Mechanically laminated decking
consists of square-edged dimension lumber laminations set on edge and nailed to the adjacent pieces and to the
supports.

2006 INTERNATIONAL BUILDING CODE 427
WOOD

International Building Code 2304.8.3.2

Nailing. The length of nails connecting laminations
shall not be less than two and one-half times the
net thickness of each lamination. Where deck supports
are 48 inches (1219 mm) on center (o.c.) or less, side
nails shall be spaced not more than 30 inches (762 mm)
o.c. alternately near top and bottom edges, and staggered
one-third of the spacing in adjacent laminations. Where
supports are spaced more than 48 inches (1219 mm) o.c.,
side nails shall be spaced not more than 18 inches (457
mm) o.c. alternately near top and bottom edges and staggered
one-third of the spacing in adjacent laminations.
Two side nails shall be used at each end of butt-jointed
pieces.
Laminations shall be toenailed to supports with 20d or
larger common nails. Where the supports are 48 inches
(1219 mm) o.c. or less, alternate laminations shall be
toenailed to alternate supports; where supports are
spaced more than 48 inches (1219 mm) o.c., alternate
laminations shall be toenailed to every support.

International Building Code 2304.8.3.3

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.
428 2006 INTERNATIONAL BUILDING CODE
WOOD

International Building Code 2304.8.4

Two-inch sawn tongue-and-groove decking.

General. Two-inch (51 mm) decking shall
have a maximum moisture content of 15 percent. Decking
shall be machined with a single tongue-and-groove
pattern. Each deck piece shall be nailed to each support
as required.

Nailing. Each piece of decking shall be
toenailed at each support with one 16d common nail
through the tongue and face-nailed with one 16d common
nail.

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.

International Building Code 2304.8.4.1

General. Two-inch (51 mm) decking shall
have a maximum moisture content of 15 percent. Decking
shall be machined with a single tongue-and-groove
pattern. Each deck piece shall be nailed to each support
as required.

International Building Code 2304.8.4.2

Nailing. Each piece of decking shall be
toenailed at each support with one 16d common nail
through the tongue and face-nailed with one 16d common
nail.

International Building Code 2304.8.4.3

Controlled random pattern. There shall be
a minimum distance of 24 inches (610 mm) between end
joints in adjacent courses. The pieces in the first and second
courses shall bear on at least two supports with end
joints in these two courses occurring on alternate supports.
A maximum of seven intervening courses shall be
permitted before this pattern is repeated.

International Building Code 2304.8.5

Three- and 4-inch sawn tongue-and-groove
decking.

General. Three-inch (76 mm) and 4-inch
(102 mm) decking shall have a maximum moisture content
of 19 percent. Decking shall be machined with a
double tongue-and-groove pattern. Deck pieces shall be
interconnected and fastened to the supports as required.

Nailing. Each piece shall be toenailed at each
support with one 40d common nail and face-nailed with
one 60d common nail. Courses shall be spiked to each
other with 8-inch (203 mm) spikes at intervals not to
exceed 30 inches (762 mm) through predrilled edge
holes penetrating to a depth of approximately 4 inches
(102 mm) and with one spike at a distance not exceeding
10 inches (254 mm) from the end of each piece.

Controlled random pattern. There shall be
a minimum distance of 48 inches (1219 mm) between
end joints in adjacent courses. Pieces not bearing over a
support are permitted to occur in interior bays, provided
the adjacent pieces in the same course continue over the
support for at least 24 inches (610 mm). This condition
shall not occur more than once in every six courses in
each interior bay.

International Building Code 2304.8.5.1

General. Three-inch (76 mm) and 4-inch
(102 mm) decking shall have a maximum moisture content
of 19 percent. Decking shall be machined with a
double tongue-and-groove pattern. Deck pieces shall be
interconnected and fastened to the supports as required.

International Building Code 2304.8.5.2

Nailing. Each piece shall be toenailed at each
support with one 40d common nail and face-nailed with
one 60d common nail. Courses shall be spiked to each
other with 8-inch (203 mm) spikes at intervals not to
exceed 30 inches (762 mm) through predrilled edge
holes penetrating to a depth of approximately 4 inches
(102 mm) and with one spike at a distance not exceeding
10 inches (254 mm) from the end of each piece.

International Building Code 2304.8.5.3

Controlled random pattern. There shall be
a minimum distance of 48 inches (1219 mm) between
end joints in adjacent courses. Pieces not bearing over a
support are permitted to occur in interior bays, provided
the adjacent pieces in the same course continue over the
support for at least 24 inches (610 mm). This condition
shall not occur more than once in every six courses in
each interior bay.

International Building Code 2304.9

Connections and fasteners.

Fastener requirements. Connections for wood
members shall be designed in accordance with the appropriate
methodology in Section 2301.2. The number and size of
fasteners connecting wood members shall not be less than
that set forth in Table 2304.9.1.

Sheathing fasteners. Sheathing nails or other
approved sheathing connectors shall be driven so that their
head or crown is flush with the surface of the sheathing.

Joist hangers and framing anchors. Connections
depending on joist hangers or framing anchors, ties
and other mechanical fastenings not otherwise covered are
permitted where approved. The vertical load-bearing capacity,
torsional moment capacity and deflection characteristics
of joist hangers shall be determined in accordance with
Section 1715.1.

Other fasteners. Clips, staples, glues and other
approved methods of fastening are permitted where
approved.

Fasteners in preservative-treated and
fire-retardant-treated wood. Fasteners for preservativetreated
and fire-retardant-treated wood shall be of hot
dipped zinc-coated galvanized steel, stainless steel, silicon
bronze or copper. The coating weights for zinc-coated fasteners
shall be in accordance with ASTM A 153.
Exception: Fasteners other than nails, timber rivets,
wood screws and lag screws shall be permitted to be of
mechanically deposited zinc coated steel with coating
weights in accordance withASTMB695, Class 55 minimum.
Fastenings for wood foundations shall be as required in
AF&PA Technical Report No. 7.

Load path. Where wall framing members are not
continuous from foundation sill to roof, the members shall
be secured to ensure a continuous load path. Where
required, sheet metal clamps, ties or clips shall be formed of
galvanized steel or other approved corrosion-resistant material
not less than 0.040 inch (1.01 mm) nominal thickness.

Framing requirements.Wood columns and posts
shall be framed to provide full end bearing. Alternatively,
column-and-post end connections shall be designed to resist
the full compressive loads, neglecting end-bearing capacity.
Column-and-post end connections shall be fastened to resist
lateral and net induced uplift forces.

International Building Code 2304.9.1

Fastener requirements. Connections for wood
members shall be designed in accordance with the appropriate
methodology in Section 2301.2. The number and size of
fasteners connecting wood members shall not be less than
that set forth in Table 2304.9.1.

International Building Code 2304.9.2

Sheathing fasteners. Sheathing nails or other
approved sheathing connectors shall be driven so that their
head or crown is flush with the surface of the sheathing.

International Building Code 2304.9.3

Joist hangers and framing anchors. Connections
depending on joist hangers or framing anchors, ties
and other mechanical fastenings not otherwise covered are
permitted where approved. The vertical load-bearing capacity,
torsional moment capacity and deflection characteristics
of joist hangers shall be determined in accordance with
Section 1715.1.

International Building Code 2304.9.4

Other fasteners. Clips, staples, glues and other
approved methods of fastening are permitted where
approved.

International Building Code 2304.9.5

Fasteners in preservative-treated and
fire-retardant-treated wood. Fasteners for preservativetreated
and fire-retardant-treated wood shall be of hot
dipped zinc-coated galvanized steel, stainless steel, silicon
bronze or copper. The coating weights for zinc-coated fasteners
shall be in accordance with ASTM A 153.
Exception: Fasteners other than nails, timber rivets,
wood screws and lag screws shall be permitted to be of
mechanically deposited zinc coated steel with coating
weights in accordance withASTMB695, Class 55 minimum.
Fastenings for wood foundations shall be as required in
AF&PA Technical Report No. 7.

International Building Code 2304.9.6

Load path. Where wall framing members are not
continuous from foundation sill to roof, the members shall
be secured to ensure a continuous load path. Where
required, sheet metal clamps, ties or clips shall be formed of
galvanized steel or other approved corrosion-resistant material
not less than 0.040 inch (1.01 mm) nominal thickness.

International Building Code 2304.9.7

Framing requirements.Wood columns and posts
shall be framed to provide full end bearing. Alternatively,
column-and-post end connections shall be designed to resist
the full compressive loads, neglecting end-bearing capacity.
Column-and-post end connections shall be fastened to resist
lateral and net induced uplift forces.