The 2006 IBC allowed stairways that were part of the required means of egress between two floors to be open without need for enclosing per the exception 11 in Section 707.2 and exceptions 8 and 9 in Section 1020.1.

The 2009 IBC does not appear to have similar exceptions. Section 708 "Shaft Enclosures" and Section 1022 "Exit Enclosures" now appear to require Stairway Enclosures for a stairway open to two floors if it is part of the required means of egress (i.e required exit stairway).

Is this correct? Was this an intentional change between the 2006 and 2009 IBC?

Thank you.
Original Post
Is this what you are looking for?

CBC 2010
1022.1 Enclosures required.
Exceptions
1. In all occupancies, other than Group H, I and R-2.1 occupancies, a stairway is not required to be enclosed when the stairway serves an occupant load of less than 10 and the stairway complies with either Item 1.1 or 1.2. In all cases, the maximum number of connecting open stories shall not exceed two.
1.1. The stairway is open to not more than one story above its level of exit discharge; or
1.2. The stairway is open to not more than one story below its level of exit discharge.

6. Means of egress stairways as required by Sections 410.5.3 and 1015.6.1 are not required to be enclosed.
I saw that Mark...but the exception limits stairways to an occupant load served of less than 10.

So if you have a stairway serving an occupant load of 10 or more and connecting only between two floors, the 2010 CBC (2009 IBC) appears to require that the stairway be "enclosed".

This would be a significant departure from the 2006 IBC (2007 CBC) where the same stairway would be allowed between two floors without the need to enclose (i.e. it can be an open stairway).
Thanks Mark and Ron.

The stairs are part of the required means of egress in this case and will have to be enclosed it appears using the 2010 CBC (2009 IBC).

For 2-story buildings where the egress stairs between the floors were OK to remain open using the 2007 CBC (2006 IBC), now would have to be enclosed using the 2010 CBC (2009 IBC). This will take getting used to.
Good issue.

I reviewed the "Siginificant Changes...." and found that Exceptions 8 & 9 to previous section 1020.1 have been deleted. But, they were moved to Section 1016.1. It appears that if the travel distance complies then the exit stairway is not required to be enclosed.

Take a look and please respond.
Chuck Daleo
Chuck:

Nice catch. You're right. Same result--different approach. In my opinion, this is more confusing, but I'm sure everyone will get use to it.

Notice that the exceptions show exit access stairways italicized, which means these are defined terms. Although "exit access stairway" itself is not defined, but "exit access" and "stairway" are defined. Thus, when the terms are used together, it defines a stairway that leads to an exit and is not an "exit" itself as the earlier 2006 exceptions would lead some to believe.

The exceptions used in the vertical exit enclosure section of previous IBC editions did not use this combination; they used "egress stairways," and the 2006 IBC added "unenclosed exit stairways." The 2006 revision would make some think that the stair, although not enclosed, was an exit. In this case, I think the 2009 IBC has clarified terminology for the better.
In my opinion, the restrictions of 1022.1 still exist.
1016 does not cancel 1022.1


708.2 Shaft enclosure required.
Exceptions:
A shaft enclosure shall not be required for floor openings created by unenclosed stairs or ramps in accordance with Exception 3 or 4 in Section 1016.1.

SECTION 1016
EXIT ACCESS TRAVEL DISTANCE
Exceptions:
3. In other than occupancy Groups H and I, the exit access travel distance to a maximum of 50 percent of the exits is permitted to be measured from the most remote point within a building to an exit using unenclosed exit
access stairways or ramps when connecting a maximum of two stories. The two connected stories shall be provided with at least two means of egress. Such interconnected stories shall not be open to other stories.

4. In other than occupancy Groups H and I, exit access travel distance is permitted to be measured from the most remote point within a building to an exit using unenclosed exit access stairways or ramps in the first and second stories above grade plane in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1. The first and second stories above grade plane shall be provided with at least two means of egress. Such interconnected stories shall not be open to other stories.
Handler:

That's my point exactly in regard to definitions. Section 1022.1 applies to "interior exit stairways" (notice the italics) and not "exit access stairways" as used in the Section 1016.1 exceptions.

Exit stairways must be enclosed with an exit enclosure. Exit access stairways can be unenclosed as long as they comply with the exceptions 3 or 4 of Section 1016.1.
So if there are two stairs IN a space [a platform area in an E-occupancy 6000sf, non sprinkled multipurpose room of single story, type 5B construction], which itself is open to the rest of the building, does code require any type of enclosure?

As an aside, the change in elevation is less than 30-inches, and a lift is included.
Mikeelia:

I'd like to know what citation the reviewer is referencing to support that position.

To further explain my response...

A platform is not a floor or story, so there is no "opening" to protect with a shaft.

Also, the stairs are not "exit" stairs, which the 2006 IBC uses when describing requirements for vertical exit enclosures (like the 2009 IBC). But they are considered stairways within the exit access. Thus, travel along unenclosed stairs (i.e. stairways within the exit access) is permitted as long as the travel distance and common path of egress travel distance is not exceeded.
Ron,
The review comment is this:
"3. Indicate compliance with CBC 1017.1, "E" occupancy load greater than 10, corridor with fire resistance rating req'd. Provide new design in case an exception is used."

The "3" points to the two open stairs at the sides of the platform which pass by the toilet room doors.

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