International Building Code Section 406


International Building Code 406.1

Private garages and carports.

Classification. Buildings or parts of buildings classified
as Group U occupancies because of the use or character
of the occupancy shall not exceed 1,000 square feet (93
m2) in area or one story in height except as provided in Section
406.1.2. Any building or portion thereof that exceeds
the limitations specified in this section shall be classified in
the occupancy group other than Group U that it most nearly
resembles.

Area increase. Group U occupancies used for the
storage of private or pleasure-type motor vehicles where no
repair work is completed or fuel is dispensed are permitted
to be 3,000 square feet (279 m2) when the following provisions
are met:
1. For a mixed occupancy building, the exterior wall and
opening protection for the Group U portion of the
building shall be as required for the major occupancy
of the building. For such a mixed occupancy building,
the allowable floor area of the building shall be as permitted
for the major occupancy contained therein.
2. For a building containing only a Group U occupancy,
the exterior wall shall not be required to have a
fire-resistance rating and the area of openings shall
not be limited when the fire separation distance is 5
feet (1524 mm) or more.
More than one 3,000-square-foot (279 m2) Group U
occupancy shall be permitted to be in the same building,
provided each 3,000-square-foot (279 m2) area is separated
by fire walls complying with Section 705.

Garages and carports. Carports shall be open on at
least two sides. Carport floor surfaces shall be of approved
noncombustible material. Carports not open on at least two
sides shall be considered a garage and shall comply with the
provisions of this section for garages.
Exception: Asphalt surfaces shall be permitted at
ground level in carports.
The area of floor used for parking of automobiles or other
vehicles shall be sloped to facilitate the movement of liquids
to a drain or toward the main vehicle entry doorway.

Separation. Separations shall comply with the
following:
1. The private garage shall be separated from the dwelling
unit and its attic area by means of a minimum
1/2-inch (12.7 mm) gypsum board applied to the
garage side. Garages beneath habitable rooms shall be
separated from all habitable rooms above by not less
than a 5/8-inch Type X gypsum board or equivalent.
Door openings between a private garage and the
dwelling unit shall be equipped with either solid
wood doors or solid or honeycomb core steel doors
not less than 13/8 inches (34.9 mm) thick, or doors in
compliance with Section 715.4.3. Openings from a
private garage directly into a room used for sleeping
purposes shall not be permitted. Doors shall be
self-closing and self-latching.
2. Ducts in a private garage and ducts penetrating the
walls or ceilings separating the dwelling unit from the
garage shall be constructed of a minimum 0.019-inch
(0.48 mm) sheet steel and shall have no openings into
the garage.
3. Aseparation is not required between a Group R-3 and
Ucarport, provided the carport is entirely open on two
or more sides and there are not enclosed areas above.

International Building Code 406.1.1

Classification. Buildings or parts of buildings classified
as Group U occupancies because of the use or character
of the occupancy shall not exceed 1,000 square feet (93
m2) in area or one story in height except as provided in Section
406.1.2. Any building or portion thereof that exceeds
the limitations specified in this section shall be classified in
the occupancy group other than Group U that it most nearly
resembles.

International Building Code 406.1.2

Area increase. Group U occupancies used for the
storage of private or pleasure-type motor vehicles where no
repair work is completed or fuel is dispensed are permitted
to be 3,000 square feet (279 m2) when the following provisions
are met:
1. For a mixed occupancy building, the exterior wall and
opening protection for the Group U portion of the
building shall be as required for the major occupancy
of the building. For such a mixed occupancy building,
the allowable floor area of the building shall be as permitted
for the major occupancy contained therein.
2. For a building containing only a Group U occupancy,
the exterior wall shall not be required to have a
fire-resistance rating and the area of openings shall
not be limited when the fire separation distance is 5
feet (1524 mm) or more.
More than one 3,000-square-foot (279 m2) Group U
occupancy shall be permitted to be in the same building,
provided each 3,000-square-foot (279 m2) area is separated
by fire walls complying with Section 705.

International Building Code 406.1.3

Garages and carports. Carports shall be open on at
least two sides. Carport floor surfaces shall be of approved
noncombustible material. Carports not open on at least two
sides shall be considered a garage and shall comply with the
provisions of this section for garages.
Exception: Asphalt surfaces shall be permitted at
ground level in carports.
The area of floor used for parking of automobiles or other
vehicles shall be sloped to facilitate the movement of liquids
to a drain or toward the main vehicle entry doorway.

International Building Code 406.1.4

Separation. Separations shall comply with the
following:
1. The private garage shall be separated from the dwelling
unit and its attic area by means of a minimum
1/2-inch (12.7 mm) gypsum board applied to the
garage side. Garages beneath habitable rooms shall be
separated from all habitable rooms above by not less
than a 5/8-inch Type X gypsum board or equivalent.
Door openings between a private garage and the
dwelling unit shall be equipped with either solid
wood doors or solid or honeycomb core steel doors
not less than 13/8 inches (34.9 mm) thick, or doors in
compliance with Section 715.4.3. Openings from a
private garage directly into a room used for sleeping
purposes shall not be permitted. Doors shall be
self-closing and self-latching.
2. Ducts in a private garage and ducts penetrating the
walls or ceilings separating the dwelling unit from the
garage shall be constructed of a minimum 0.019-inch
(0.48 mm) sheet steel and shall have no openings into
the garage.
3. Aseparation is not required between a Group R-3 and
Ucarport, provided the carport is entirely open on two
or more sides and there are not enclosed areas above.

International Building Code 406.2.1

Classification. Parking garages shall be classified
as either open, as defined in Section 406.3, or enclosed and
shall meet the appropriate criteria in Section 406.4. Also see
Section 509 for special provisions for parking garages.

International Building Code 406.2.2

Clear height. The clear height of each floor level in
vehicle and pedestrian traffic areas shall not be less than 7
feet (2134 mm). Vehicle and pedestrian areas accommodating
van-accessible parking required by Section 1106.5 shall
conform to ICC A117.1.

International Building Code 406.2.3

Guards. Guards shall be provided in accordance
with Section 1012 at exterior and interior vertical openings
on floor and roof areas where vehicles are parked or moved
and where the vertical distance to the ground or surface
directly below exceeds 30 inches (762 mm).

International Building Code 406.2.4

Vehicle barriers. Parking areas shall be provided
with exterior or interior walls or vehicle barriers, except at
pedestrian or vehicular accesses, designed in accordance
with Section 1607.7. Vehicle barriers not less than 2 feet
(607 mm) high shall be placed at the end of drive lanes, and
at the end of parking spaces where the difference in adjacent
floor elevation is greater than 1 foot (305 mm).
Exception: Vehicle storage compartments in a mechanical
access parking garage.

International Building Code 406.2.5

Ramps. Vehicle ramps shall not be considered as
required exits unless pedestrian facilities are provided.
Vehicle ramps that are utilized for vertical circulation as
well as for parking shall not exceed a slope of 1:15 (6.67
percent).

Floor surface. Parking surfaces shall be of concrete
or similar noncombustible and nonabsorbent materials.
Exception: Asphalt parking surfaces are permitted at
ground level.
The area of floor used for parking of automobiles or other
vehicles shall be sloped to facilitate the movement of liquids
to a drain or toward the main vehicle entry doorway.

Mixed separation. Parking garages shall be separated
from other occupancies in accordance with Section
508.3.

Special hazards. Connection of a parking garage
with any room in which there is a fuel-fired appliance shall
be by means of a vestibule providing a two-doorway separation.
Exception: A single door shall be allowed provided the
sources of ignition in the appliance are at least 18 inches
(457 mm) above the floor.

Attached to rooms. Openings from a parking
garage directly into a room used for sleeping purposes shall
not be permitted.

International Building Code 406.2.6

Floor surface. Parking surfaces shall be of concrete
or similar noncombustible and nonabsorbent materials.
Exception: Asphalt parking surfaces are permitted at
ground level.
The area of floor used for parking of automobiles or other
vehicles shall be sloped to facilitate the movement of liquids
to a drain or toward the main vehicle entry doorway.

International Building Code 406.2.7

Mixed separation. Parking garages shall be separated
from other occupancies in accordance with Section
508.3.

International Building Code 406.2.8

Special hazards. Connection of a parking garage
with any room in which there is a fuel-fired appliance shall
be by means of a vestibule providing a two-doorway separation.
Exception: A single door shall be allowed provided the
sources of ignition in the appliance are at least 18 inches
(457 mm) above the floor.

International Building Code 406.2.9

Attached to rooms. Openings from a parking
garage directly into a room used for sleeping purposes shall
not be permitted.

International Building Code 406.3.1

Scope. Except where specific provisions are made
in the following subsections, other requirements of this
code shall apply.

International Building Code 406.3.10

Sprinkler systems. Where required by other provisions
of this code, automatic sprinkler systems and
standpipes shall be installed in accordance with the provisions
of Chapter 9.

International Building Code 406.3.11

Enclosure of vertical openings. Enclosure shall
not be required for vertical openings except as specified in
Section 406.3.8.

International Building Code 406.3.12

Ventilation.Ventilation, other than the percentage
of openings specified in Section 406.3.3.1, shall not be
required.

International Building Code 406.3.13

Prohibitions. The following uses and alterations
are not permitted:
1. Vehicle repair work.
2. Parking of buses, trucks and similar vehicles.

TABLE 406.3.5
OPEN PARKING GARAGES AREA AND HEIGHT
TYPE OF CONSTRUCTION

International Building Code 406.3.2

Definitions. The following words and terms shall,
for the purposes of this chapter and as used elsewhere in this
code, have the meanings shown herein.
MECHANICAL-ACCESS OPEN PARKING
GARAGES. Open parking garages employing parking
machines, lifts, elevators or other mechanical devices for
vehicles moving from and to street level and in which public
occupancy is prohibited above the street level.
OPEN PARKING GARAGE. A structure or portion of a
structure with the openings as described in Section
406.3.3.1 on two or more sides that is used for the parking or
storage of private motor vehicles as described in Section
406.3.4.
RAMP-ACCESS OPEN PARKING GARAGES. Open
parking garages employing a series of continuously rising
floors or a series of interconnecting ramps between floors
permitting the movement of vehicles under their own power
from and to the street level.

International Building Code 406.3.3.1

Openings. For natural ventilation purposes,
the exterior side of the structure shall have uniformly distributed
openings on two or more sides. The area of such
openings in exterior walls on a tier must be at least 20
percent of the total perimeter wall area of each tier. The
aggregate length of the openings considered to be providing
natural ventilation shall constitute a minimum of
40 percent of the perimeter of the tier. Interior walls shall
be at least 20 percent open with uniformly distributed
openings.
Exception: Openings are not required to be distributed
over 40 percent of the building perimeter where
the required openings are uniformly distributed over
two opposing sides of the building.

International Building Code 406.3.4

Uses. Mixed uses shall be allowed in the same
building as an open parking garage subject to the provisions
of Sections 508.3, 402.7.1, 406.3.13, 509.3, 509.4 and
509.7.

International Building Code 406.3.5

Area and height. Area and height of open parking
garages shall be limited as set forth in Chapter 5 for Group
S-2 occupancies and as further provided for in Section
508.3.

Single use. When the open parking garage is
used exclusively for the parking or storage of private
motor vehicles, with no other uses in the building, the
area and height shall be permitted to comply with Table
406.3.5, along with increases allowed by Section
406.3.6.
Exception: The grade-level tier is permitted to contain
an office, waiting and toilet rooms having a total
combined area of not more than 1,000 square feet (93
m2). Such area need not be separated from the open
parking garage.
In open parking garages having a spiral or sloping
floor, the horizontal projection of the structure at any
cross section shall not exceed the allowable area per
parking tier. In the case of an open parking garage having
a continuous spiral floor, each 9 feet 6 inches (2896 mm)
of height, or portion thereof, shall be considered a tier.
The clear height of a parking tier shall not be less than
7 feet (2134 mm), except that a lower clear height is permitted
in mechanical-access open parking garages where
approved by the building official.

International Building Code 406.3.6

Area and height increases. The allowable area and
height of open parking garages shall be increased in accordance
with the provisions of this section. Garages with sides
open on three-fourths of the building’s perimeter are permitted
to be increased by 25 percent in area and one tier in
height. Garages with sides open around the entire building’s
perimeter are permitted to be increased by 50 percent in area
and one tier in height. For a side to be considered open under
the above provisions, the total area of openings along the
side shall not be less than 50 percent of the interior area of
the side at each tier and such openings shall be equally distributed
along the length of the tier.
Allowable tier areas in Table 406.3.5 shall be increased
for open parking garages constructed to heights less than the
table maximum. The gross tier area of the garage shall not
exceed that permitted for the higher structure. At least three
sides of each such larger tier shall have continuous horizontal
openings not less than 30 inches (762 mm) in clear height
extending for at least 80 percent of the length of the sides
and no part of such larger tier shall be more than 200 feet (60
960 mm) horizontally from such an opening. In addition,
each such opening shall face a street or yard accessible to a
street with a width of at least 30 feet (9144 mm) for the full
length of the opening, and standpipes shall be provided in
each such tier.
Open parking garages of Type II construction, with all
sides open, shall be unlimited in allowable area where the
height does not exceed 75 feet (22 860 mm). For a side to be
considered open, the total area of openings along the side
shall not be less than 50 percent of the interior area of the
side at each tier and such openings shall be equally distributed
along the length of the tier. All portions of tiers shall be
within 200 feet (60 960 mm) horizontally from such openings
or other natural ventilation openings as defined in Section
406.3.3.1. These openings shall be permitted to be
provided in courts with a minimum width of 30 feet (9144
mm) for the full width of the openings.

International Building Code 406.3.9

Standpipes. Standpipes shall be installed where
required by the provisions of Chapter 9.

International Building Code 406.4

Enclosed parking garages.

Heights and areas. Enclosed vehicle parking
garages and portions thereof that do not meet the definition
of open parking garages shall be limited to the allowable
heights and areas specified in Table 503 as modified by Sections
504, 506 and 507. Roof parking is permitted.

Ventilation. A mechanical ventilation system shall
be provided in accordance with the International Mechanical
Code.

International Building Code 406.4.1

Heights and areas. Enclosed vehicle parking
garages and portions thereof that do not meet the definition
of open parking garages shall be limited to the allowable
heights and areas specified in Table 503 as modified by Sections
504, 506 and 507. Roof parking is permitted.

International Building Code 406.4.2

Ventilation. A mechanical ventilation system shall
be provided in accordance with the International Mechanical
Code.

International Building Code 406.5

Motor fuel-dispensing facilities.

Construction. Motor fuel-dispensing facilities
shall be constructed in accordance with the International
Fire Code and this section.

Canopies. Canopies under which fuels are dispensed
shall have a clear, unobstructed height of not less
than 13 feet 6 inches (4115 mm) to the lowest projecting element
in the vehicle drive-through area. Canopies and their
supports over pumps shall be of noncombustible materials,
fire-retardant-treated wood complying with Chapter 23,
wood of Type IV sizes or of construction providing 1-hour
fire resistance. Combustible materials used in or on a canopy
shall comply with one of the following:
1. Shielded from the pumps by a noncombustible element
of the canopy, or wood of Type IV sizes;
2. Plastics covered by aluminum facing having a minimum
thickness of 0.010 inch (0.30 mm) or corrosion-
resistant steel having a minimum base metal
thickness of 0.016 inch (0.41 mm). The plastic shall
have a flame spread index of 25 or less and a
smoke-developed index of 450 or less when tested in
the form intended for use in accordance withASTME
84 and a self-ignition temperature of 650F (343C)
or greater when tested in accordance with ASTM D
1929; or
3. Panels constructed of light-transmitting plastic materials
shall be permitted to be installed in canopies
erected over motor vehicle fuel-dispensing station
fuel dispensers, provided the panels are located at
least 10 feet (3048 mm) from any building on the
same lot and face yards or streets not less than 40 feet
(12 192 mm) in width on the other sides. The aggregate
areas of plastics shall not exceed 1,000 square
feet (93 m2). The maximum area of any individual
panel shall not exceed 100 square feet (9.3 m2).

Canopies used to support gaseous hydrogen
systems. Canopies that are used to shelter dispensing
operations where flammable compressed gases are
located on the roof of the canopy shall be in accordance
with the following:
1. The canopy shall meet or exceed Type I construction
requirements.
2. Operations located under canopies shall be limited
to refueling only.
3. The canopy shall be constructed in a manner that
prevents the accumulation of hydrogen gas.

International Building Code 406.5.1

Construction. Motor fuel-dispensing facilities
shall be constructed in accordance with the International
Fire Code and this section.

International Building Code 406.5.2

Canopies. Canopies under which fuels are dispensed
shall have a clear, unobstructed height of not less
than 13 feet 6 inches (4115 mm) to the lowest projecting element
in the vehicle drive-through area. Canopies and their
supports over pumps shall be of noncombustible materials,
fire-retardant-treated wood complying with Chapter 23,
wood of Type IV sizes or of construction providing 1-hour
fire resistance. Combustible materials used in or on a canopy
shall comply with one of the following:
1. Shielded from the pumps by a noncombustible element
of the canopy, or wood of Type IV sizes;
2. Plastics covered by aluminum facing having a minimum
thickness of 0.010 inch (0.30 mm) or corrosion-
resistant steel having a minimum base metal
thickness of 0.016 inch (0.41 mm). The plastic shall
have a flame spread index of 25 or less and a
smoke-developed index of 450 or less when tested in
the form intended for use in accordance withASTME
84 and a self-ignition temperature of 650F (343C)
or greater when tested in accordance with ASTM D
1929; or
3. Panels constructed of light-transmitting plastic materials
shall be permitted to be installed in canopies
erected over motor vehicle fuel-dispensing station
fuel dispensers, provided the panels are located at
least 10 feet (3048 mm) from any building on the
same lot and face yards or streets not less than 40 feet
(12 192 mm) in width on the other sides. The aggregate
areas of plastics shall not exceed 1,000 square
feet (93 m2). The maximum area of any individual
panel shall not exceed 100 square feet (9.3 m2).

Canopies used to support gaseous hydrogen
systems. Canopies that are used to shelter dispensing
operations where flammable compressed gases are
located on the roof of the canopy shall be in accordance
with the following:
1. The canopy shall meet or exceed Type I construction
requirements.
2. Operations located under canopies shall be limited
to refueling only.
3. The canopy shall be constructed in a manner that
prevents the accumulation of hydrogen gas.

International Building Code 406.5.2.1

Canopies used to support gaseous hydrogen
systems. Canopies that are used to shelter dispensing
operations where flammable compressed gases are
located on the roof of the canopy shall be in accordance
with the following:
1. The canopy shall meet or exceed Type I construction
requirements.
2. Operations located under canopies shall be limited
to refueling only.
3. The canopy shall be constructed in a manner that
prevents the accumulation of hydrogen gas.

International Building Code 406.6

Repair garages.

General. Repair garages shall be constructed in
accordance with the International Fire Code and this section.
This occupancy shall not include motor fuel-dispensing
facilities, as regulated in Section 406.5.

Mixed uses. Mixed uses shall be allowed in the
same building as a repair garage subject to the provisions of
Section 508.3.

Ventilation. Repair garages shall be mechanically
ventilated in accordance with the International Mechanical
Code. The ventilation system shall be controlled at the
entrance to the garage.

Floor surface. Repair garage floors shall be of concrete
or similar noncombustible and nonabsorbent materials.
Exception: Slip-resistant, nonabsorbent, interior floor
finishes having a critical radiant flux not more than 0.45
W/cm2, as determined by NFPA253, shall be permitted.

Heating equipment. Heating equipment shall be
installed in accordance with the International Mechanical
Code.

Gas detection system. Repair garages used for
repair of vehicles fueled by nonodorized gases, such as
hydrogen and nonodorized LNG, shall be provided with an
approved flammable gas-detection system.
<section name=”section 406.6.6.1″>
System design. The flammable gas-detection
system shall be calibrated to the types of fuels or
gases used by vehicles to be repaired. The gas detection
system shall be designed to activate when the level of
flammable gas exceeds 25 percent of the lower explosive
limit. Gas detection shall also be provided in lubrication
or chassis repair pits of garages used for repairing
non-odorized LNG-fueled vehicles.

Operation. Activation of the gas detection
system shall result in all of the following:
1. Initiation of distinct audible and visual alarm signals
in the repair garage.
2. Deactivation of all heating systems located in the
repair garage.
3. Activation of the mechanical ventilation system,
where the system is interlocked with gas detection.

Failure of the gas detection system. Failure
of the gas detection system shall result in the deactivation
of the heating system, activation of the
mechanical ventilation system when the system is interlocked
with the gas detection system and cause a trouble
signal to sound in an approved location.

International Building Code 406.6.1

General. Repair garages shall be constructed in
accordance with the International Fire Code and this section.
This occupancy shall not include motor fuel-dispensing
facilities, as regulated in Section 406.5.

International Building Code 406.6.2

Mixed uses. Mixed uses shall be allowed in the
same building as a repair garage subject to the provisions of
Section 508.3.

International Building Code 406.6.3

Ventilation. Repair garages shall be mechanically
ventilated in accordance with the International Mechanical
Code. The ventilation system shall be controlled at the
entrance to the garage.

International Building Code 406.6.4

Floor surface. Repair garage floors shall be of concrete
or similar noncombustible and nonabsorbent materials.
Exception: Slip-resistant, nonabsorbent, interior floor
finishes having a critical radiant flux not more than 0.45
W/cm2, as determined by NFPA253, shall be permitted.

International Building Code 406.6.5

Heating equipment. Heating equipment shall be
installed in accordance with the International Mechanical
Code.

International Building Code 406.6.6

Gas detection system. Repair garages used for
repair of vehicles fueled by nonodorized gases, such as
hydrogen and nonodorized LNG, shall be provided with an
approved flammable gas-detection system.
<section name=”section 406.6.6.1″>
System design. The flammable gas-detection
system shall be calibrated to the types of fuels or
gases used by vehicles to be repaired. The gas detection
system shall be designed to activate when the level of
flammable gas exceeds 25 percent of the lower explosive
limit. Gas detection shall also be provided in lubrication
or chassis repair pits of garages used for repairing
nonodorized LNG-fueled vehicles.

International Building Code 406.6.6.2

Operation. Activation of the gas detection
system shall result in all of the following:
1. Initiation of distinct audible and visual alarm signals
in the repair garage.
2. Deactivation of all heating systems located in the
repair garage.
3. Activation of the mechanical ventilation system,
where the system is interlocked with gas detection.

International Building Code 406.6.6.3

Failure of the gas detection system. Failure
of the gas detection system shall result in the deactivation
of the heating system, activation of the
mechanical ventilation system when the system is interlocked
with the gas detection system and cause a trouble
signal to sound in an approved location.

International Building Code sectin 406.3.5.1

Single use. When the open parking garage is
used exclusively for the parking or storage of private
motor vehicles, with no other uses in the building, the
area and height shall be permitted to comply with Table
406.3.5, along with increases allowed by Section
406.3.6.
Exception: The grade-level tier is permitted to contain
an office, waiting and toilet rooms having a total
combined area of not more than 1,000 square feet (93
m2). Such area need not be separated from the open
parking garage.
In open parking garages having a spiral or sloping
floor, the horizontal projection of the structure at any
cross section shall not exceed the allowable area per
parking tier. In the case of an open parking garage having
a continuous spiral floor, each 9 feet 6 inches (2896 mm)
of height, or portion thereof, shall be considered a tier.
The clear height of a parking tier shall not be less than
7 feet (2134 mm), except that a lower clear height is permitted
in mechanical-access open parking garages where
approved by the building official.

International Building Code sectin 406.3.8

Means of egress. Where persons other than parking
attendants are permitted, open parking garages shall meet
the means of egress requirements of Chapter 10. Where no
persons other than parking attendants are permitted, there
shall not be less than two 36-inch-wide (914 mm) exit stairways.
Lifts shall be permitted to be installed for use of
employees only, provided they are completely enclosed by
noncombustible materials.