Building planning, means of egress, and accessibility
Domain 2 tests building planning and life safety: height and area, types of construction, means of egress, and accessibility. The exam expects you to apply tables rather than memorize isolated numbers.
Height and area
Chapter 5 limits building height in feet and stories and allowable area per story. Table 506.2 gives allowable area by occupancy and type of construction; frontage increases and sprinkler increases modify it. Chapter 6 defines Type I through Type V construction with fire-resistance ratings for structural members.
Means of egress
Egress has three parts: exit access, exit, and exit discharge. Occupant load comes from Table 1004.5. Egress width is 0.2 inch per occupant for stairs and 0.15 inch for other components, with reductions allowed in sprinklered buildings. Two exits are required when the occupant load or travel distance exceeds Table 1006.2.1 limits. Exit signs, emergency lighting, and panic hardware are inspected in the field.
Accessibility
Chapter 11 scopes accessible routes, entrances, parking, toilet rooms, and assembly seating, and adopts ICC A117.1 for technical criteria. The federal ADA Standards apply independently; an IBC-compliant route is not automatically ADA-compliant if the scoping differs.
Worked example
A B occupancy tenant space has a calculated occupant load of 60. Table 1006.2.1 permits a single exit for B occupancies only up to 49 occupants. Therefore two exits are required, regardless of the tenant's comfort. Each exit must provide clear width based on the egress capacity, and the accessible route must connect to both.
Traps
Using gross floor area where net area is required; forgetting that sprinklers can extend travel distance; measuring door width to the frame rather than the clear opening; assuming a C of O covers accessibility compliance.