The minimum egress window opening is 20 wide.
Roof egress requirements.
The top rails of a guardrail system must be 39 to 45 inches above the walking working surface 29 cfr 1926 502 b 1.
Los angeles fire code 10 means of egress 1006 numbers of exits and exit access doorways 1006 3 egress from stories or occupied roofs 1006 3 2 single exits.
A single exit or access to a single exit shall be permitted from any story or occupied roof where one of the following conditions exists.
Operation and maintenance requirements for exit routes.
Minimum 5 7 square feet of net clear opening area.
The egress window must have a glass area of not less than 8 of the total floor area of room s for which it is servicing to allow the minimum amount of sufficient natural light.
For example all means of egress shall have a ceiling height of not less than 7 feet 2134 mm the building code then lists six possible exceptions to that one stipulation.
Intermediate structural members for example midrails or screens must be installed when there is no wall or parapet wall at least 21 inches high 29 cfr 1926 502 b 2.
In summary free access to the roof from the stairwell is not required by the ibc or nfpa 101 but may be required or preferred by the local code official.
Free egress from the roof to the stairwell is required for occupied roofs but is not mandated by the ibc or nfpa 101 for unoccupied roofs.
1 each exit route must be maintained to minimize danger to employees during an emergency.
Nfpa emergency exit door requirements for locks.
The net clear opening area net clear height opening and net clear width opening.
The minimum opening area of the egress window is 5 7 square feet.
The minimum egress window opening height is 24 high.
Egress window size and dimensions first lets look at the minimum opening area required.
A the danger to employees must be minimized.
The number of exit stairs required is specified in table 1006 3 1 of the code.
This includes compliance with all of the following.
The means of egress serves a room with an occupant load above 50 people the means of egress is used in an exit enclosure or while serving a high hazard area while swinging the door should leave available at least half of the required width of a corridor hallway etc for use.
Two exits are required for occupancies up to 500 persons.