2021 CBO Building Codes and Standards
Questions and Answers Guide 2026
1. Permit extensions (IBC, IRC, • IBC, IRC, IFC: one or more extensions not to exceed 180 days
IFC, IMC, IPC) each
• IMC, IPC: not more than 1 extension, not to exceed 180 days
• Must be in writing and justifiable cause demonstrated
2. Group A Occupancy ASSEMBLY
The use of a building or structure for the gathering of persons,
or civic, religious, or social functions, recreation, food, or drink
consumption, or awaiting transportation
3. Group B Occupancy BUSINESS
Professional or service-type transactions, including storage of
records and accounts
4. Group E Occupancy EDUCATIONAL
• SIX OR MORE PERSONS for educational purposes
• Through the 12th grade
If accessory to places of worship and less than 100 persons per
room or space: it shall be A-3 occupancy
5. Group F Occupancy FACTORY
Factory industrial group: assembling/disassembling, fabricat-
ing, finishing, manufacturing, packaging, repair, or processing
operations
• That are not first classified as Group H or S occupancy
6. Group H Occupancy HIGH-HAZARD
Manufacturing, processing, generation, or storage of materi-
als
• That constitute a PHYSICAL or HEALTH hazard
• In quantities in excess of those allowed in control areas of
section 414 of the IBC
, 2021 CBO Building Codes and Standards
Questions and Answers Guide 2026
7. Group I Occupancy INSTITUTIONAL
• Persons incapable of self-preservation
Or
• Persons detained for penal/correctional purposes
* Includes hospitals, nursing homes, etc.
8. Group M Occupancy
9. Group R Occupancy RESIDENTIAL
• Does NOT apply to structures governed by the IRC
• Includes congregate living facilities (dorms, convents, etc.)
10. Provisions of the IRC Building, mechanical, and plumbing systems of
• Detached 1- and 2-family dwellings and townhouses
• Not more than 3 stories above plane grade
• With a separate means of egress
• Including accessory structures not more than 3 stories
11. Group S Occupancy STORAGE
Includes:
• Aircraft hangars used for storage OR REPAIR
• Asbestos, aerosol product, and tobacco storage
• Public parking garages
12. Group U Occupancy UTILITY AND MISCELLANEOUS
• Buildings of an accessory character, not classified in any
specific occupancy
Includes:
• Agricultural buildings
• Aircraft hangars accessory to one/two-family residence
• Carports
• Retaining walls
, • Towers
• SOME greenhouses (see Mercantile)
13. Does building height include No.
basements?
BUILDING HEIGHT (Definition):
The vertical distance from grade plane to the average height of
the highest roof surface.
14. STORY ABOVE GRADE PLANE Any story having its finished floor surface entirely above grade
(Definition) plane, or in which the finished surface of the floor next above
is:
• More than 6 feet above grade plane, or
• More than 12 feet above the finished ground level at any
point
15. Circular turning spaces shall 60 inches
be inches minimum in di- A117.1-2009, Figure 304.3
ameter.
16. HIGH-RISE BUILDING (Defini- A building with an occupied floor located more than 75 feet
tion) above the lowest level of fire department vehicle access
17. HORIZONTAL ASSEMBLY (Def- A fire-resistance-rated floor or roof assembly of materials de-
inition) signed to restrict the spread of fire in which continuity is main-
tained
18. What are the load require- Any wall meeting either of the following classifications:
ments for a wall to be consid- • Metal or wood stud wall supporting more than 100 lbs/linear
ered load-bearing? foot of vertical load in addition to its own weight
• Any masonry, concrete, or mass timber wall supporting more
than 200 lbs/linear foot in addition to its own weight
(IBC definition for "Wall, Load-Bearing")
, 19. What type(s) of construction TYPES I & II
requires building elements of
noncombustible materials?
20. What type(s) of construction TYPE III
requires (only) exterior walls
to be of noncombustible ma-
terials?
21. What type(s) of construction TYPE V
allow structural elements to
be of any materials permitted
by the IBC?
22. What type(s) of construction TYPE IV
are made of mass timber or
noncombustible materials.
23. IPC 424.2 - Substitution for Assembly and education occupancies: up to 67%
Water Closets: All other occupancies: up to 50%
How many water closets may
be substituted for urinals ac-
cording to each occupancy?
24. Fire-retardant-treated wood The exterior wall assemblies require a 2-hour fire rating or less.
framing and sheathing shall
be permitted within exterior
wall assemblies of Type III
construction when...
25. CHAPTER 5 - GENERAL BUILDING HEIGHTS AND AREAS
Table 508.4
Questions and Answers Guide 2026
1. Permit extensions (IBC, IRC, • IBC, IRC, IFC: one or more extensions not to exceed 180 days
IFC, IMC, IPC) each
• IMC, IPC: not more than 1 extension, not to exceed 180 days
• Must be in writing and justifiable cause demonstrated
2. Group A Occupancy ASSEMBLY
The use of a building or structure for the gathering of persons,
or civic, religious, or social functions, recreation, food, or drink
consumption, or awaiting transportation
3. Group B Occupancy BUSINESS
Professional or service-type transactions, including storage of
records and accounts
4. Group E Occupancy EDUCATIONAL
• SIX OR MORE PERSONS for educational purposes
• Through the 12th grade
If accessory to places of worship and less than 100 persons per
room or space: it shall be A-3 occupancy
5. Group F Occupancy FACTORY
Factory industrial group: assembling/disassembling, fabricat-
ing, finishing, manufacturing, packaging, repair, or processing
operations
• That are not first classified as Group H or S occupancy
6. Group H Occupancy HIGH-HAZARD
Manufacturing, processing, generation, or storage of materi-
als
• That constitute a PHYSICAL or HEALTH hazard
• In quantities in excess of those allowed in control areas of
section 414 of the IBC
, 2021 CBO Building Codes and Standards
Questions and Answers Guide 2026
7. Group I Occupancy INSTITUTIONAL
• Persons incapable of self-preservation
Or
• Persons detained for penal/correctional purposes
* Includes hospitals, nursing homes, etc.
8. Group M Occupancy
9. Group R Occupancy RESIDENTIAL
• Does NOT apply to structures governed by the IRC
• Includes congregate living facilities (dorms, convents, etc.)
10. Provisions of the IRC Building, mechanical, and plumbing systems of
• Detached 1- and 2-family dwellings and townhouses
• Not more than 3 stories above plane grade
• With a separate means of egress
• Including accessory structures not more than 3 stories
11. Group S Occupancy STORAGE
Includes:
• Aircraft hangars used for storage OR REPAIR
• Asbestos, aerosol product, and tobacco storage
• Public parking garages
12. Group U Occupancy UTILITY AND MISCELLANEOUS
• Buildings of an accessory character, not classified in any
specific occupancy
Includes:
• Agricultural buildings
• Aircraft hangars accessory to one/two-family residence
• Carports
• Retaining walls
, • Towers
• SOME greenhouses (see Mercantile)
13. Does building height include No.
basements?
BUILDING HEIGHT (Definition):
The vertical distance from grade plane to the average height of
the highest roof surface.
14. STORY ABOVE GRADE PLANE Any story having its finished floor surface entirely above grade
(Definition) plane, or in which the finished surface of the floor next above
is:
• More than 6 feet above grade plane, or
• More than 12 feet above the finished ground level at any
point
15. Circular turning spaces shall 60 inches
be inches minimum in di- A117.1-2009, Figure 304.3
ameter.
16. HIGH-RISE BUILDING (Defini- A building with an occupied floor located more than 75 feet
tion) above the lowest level of fire department vehicle access
17. HORIZONTAL ASSEMBLY (Def- A fire-resistance-rated floor or roof assembly of materials de-
inition) signed to restrict the spread of fire in which continuity is main-
tained
18. What are the load require- Any wall meeting either of the following classifications:
ments for a wall to be consid- • Metal or wood stud wall supporting more than 100 lbs/linear
ered load-bearing? foot of vertical load in addition to its own weight
• Any masonry, concrete, or mass timber wall supporting more
than 200 lbs/linear foot in addition to its own weight
(IBC definition for "Wall, Load-Bearing")
, 19. What type(s) of construction TYPES I & II
requires building elements of
noncombustible materials?
20. What type(s) of construction TYPE III
requires (only) exterior walls
to be of noncombustible ma-
terials?
21. What type(s) of construction TYPE V
allow structural elements to
be of any materials permitted
by the IBC?
22. What type(s) of construction TYPE IV
are made of mass timber or
noncombustible materials.
23. IPC 424.2 - Substitution for Assembly and education occupancies: up to 67%
Water Closets: All other occupancies: up to 50%
How many water closets may
be substituted for urinals ac-
cording to each occupancy?
24. Fire-retardant-treated wood The exterior wall assemblies require a 2-hour fire rating or less.
framing and sheathing shall
be permitted within exterior
wall assemblies of Type III
construction when...
25. CHAPTER 5 - GENERAL BUILDING HEIGHTS AND AREAS
Table 508.4
