ICC System Architecture and Design 3 — Questions and Answers
Question 1: Under the IBC, which construction type requires all structural members, including floors and roofs, to be of noncombustible materials with specific fire-resistance ratings for columns and beams?
- Type I-A (Correct answer)
- Type II-A
- Type III-A
- Type IV-HT
Correct answer: Type I-A
Type I-A construction requires all structural elements to be noncombustible with the highest fire-resistance ratings (3 hours for columns/beams, 2 hours for floors).
Question 2: What is the primary purpose of a building's 'diaphragm' in lateral force resistance system design?
- To separate floors of different occupancies
- To collect and transfer lateral forces to vertical resisting elements (Correct answer)
- To provide waterproofing between foundation levels
- To distribute gravity loads to columns
Correct answer: To collect and transfer lateral forces to vertical resisting elements
A diaphragm (floor or roof system) collects lateral forces from wind or seismic events and transfers them horizontally to shear walls or braced frames.
Question 3: According to IBC Section 403, which of the following is NOT a required system in high-rise buildings?
- Automatic sprinkler system throughout
- Emergency voice/alarm communication system
- Smoke control system for all floors (Correct answer)
- Standby power system
Correct answer: Smoke control system for all floors
IBC Section 403 requires sprinklers, emergency voice/alarm, and standby power in high-rises, but does not mandate a smoke control system for all floors in every high-rise.
Question 4: In IBC mixed-occupancy design using the 'separated occupancies' method, fire barriers between occupancies must meet what minimum rating requirement?
- The rating specified in IBC Table 508.4 for the occupancy pair (Correct answer)
- 1 hour for all mixed-use buildings
- 2 hours whenever an H occupancy is present
- The highest rating required by either occupancy alone
Correct answer: The rating specified in IBC Table 508.4 for the occupancy pair
IBC Table 508.4 specifies the required fire barrier rating between each pair of separated occupancies, which varies based on the specific combination.
Question 5: What structural concept does 'redundancy' refer to in seismic design of building systems?
- Providing duplicate mechanical equipment for backup
- Having multiple lateral force-resisting elements so failure of one does not cause collapse (Correct answer)
- Using extra fasteners beyond minimum code requirements
- Installing secondary roof drainage to prevent ponding
Correct answer: Having multiple lateral force-resisting elements so failure of one does not cause collapse
Structural redundancy means designing multiple lateral load-resisting elements so that if one fails, the system can redistribute loads without progressive collapse.
Question 6: Which IBC table is used to determine the allowable building height in feet for a given occupancy group and construction type?
- Table 503
- Table 504.3 (Correct answer)
- Table 506.2
- Table 602
Correct answer: Table 504.3
IBC Table 504.3 specifies the maximum allowable height in feet for each combination of occupancy group and construction type.
Question 7: In ICC building design, what is a 'transfer structure'?
- A stairwell designed for occupant transfer between floors during emergencies
- A horizontal structural element that redirects loads from upper columns to different support points below (Correct answer)
- A beam that transfers gravity loads to the perimeter foundation
- A slab system that transfers lateral loads to a core wall
Correct answer: A horizontal structural element that redirects loads from upper columns to different support points below
A transfer structure (such as a transfer beam or plate) redirects vertical loads from columns or walls above to support points that do not align with those above.
ICC System Architecture and Design 3
Under the IBC, which construction type requires all structural members, including floors and roofs, to be of noncombustible materials with specific fire-resistance ratings for columns and beams?