open stairs in existing building

[Warrior]

Hello,

I'm working on an interior renovation of a non-sprinklered one story building with a basement under the IEBC 2009 with the scope of work classified as a Level 2 Alteration (work area is less than 50% of aggregate area). My question:

There are two unenclosed stairs leading from the basement to the ground level. Neither are enclosed. The basement will be an assembly area capable of seating 100+ occupants. Am I required to enclose the stairs?

Please let me know if this inquiry requires additional info for a response. My first post!

Thank you!

 

[cda]

Welcome ....

 

[cda]

Not even fluent with iebc

But

How many sq ft is the basement

I am taking change of use??

So why isn't the basement going to be sprinkled?

What is the total occupant load

Appears if it was new the stairs would have to be enclosed.

And if over 300 occupant load would have to have an exit to the street

 

[mtlogcabin]

703.2.1 Existing vertical openings.

All existing interior vertical openings connecting two or more floors shall be enclosed with approved assemblies having a fire-resistance rating of not less than 1 hour with approved opening protectives.

Exceptions:

4. In Group A occupancies, a minimum 30-minute enclosure shall be provided to protect all vertical openings not exceeding three stories.

This should include the stairs since it is not sprinklered

 

[RLGA]

Is the assembly area existing in the basement, or is this a new use? If the latter, then it is not a Level 2 alteration--it is a change of occupancy and must comply with all the requirements of the IBC, whether it's directed by IEBC Chapter 9 of the Work Area Compliance Method or IEBC Section 307 of the Prescriptive Compliance Method. However, IBC Section 1016.1, Exception 3, allows 50% of the exits to use an unenclosed stairway (exit access stairway) when connecting a maximum of two stories.

Further, regardless of which assembly occupancy group is in the basement, if this is a change in occupancy as I stated above, then the basement would be required to be sprinklered, since the Group A fire area is on a floor other than the level of exit discharge per IBC Section 903.2.1.

 

[cda]

does this only pertain to """1028.5 Interior balcony and gallery means of egress."""" ??? or any stair in the assembly?

1028.5.1 Enclosure of openings. Interior stairways and other vertical openings shall be enclosed in an exit enclosure as provided in Section 1022.1, except that stairways are permitted to be open between the balcony, gallery or press box and the main assembly floor in occupancies such as theaters, places of religious worship, auditoriums and sports facilities. At least one accessible means of egress is required from a balcony, gallery or press box level containing accessible seating locations in accordance with Section 1007.3 or 1007.4.

 

[mtlogcabin]

A change in occupancy may not trigger the sprinklers under the IEBC. A change in occupancy classification does. It can be confusing with the similar language. I agree you are probably going to have to sprinkle the basement unless it is an existing A-3 use

901.3 Change of occupancy classification.

Where the occupancy classification of a building changes, the provisions of Sections 902 through 912 shall apply. This includes a change of occupancy classification within a group as well as a change of occupancy classification from one group to a different group.

912.1 General.

The provisions of this section shall apply to buildings or portions thereof undergoing a change of occupancy classification. This includes a change of occupancy classification within a group as well as a change of occupancy classification from one group to a different group. Such buildings shall also comply with Sections 902 through 911. The application of requirements for the change of occupancy shall be as set forth in Sections 912.1.1 through 912.1.4. A change of occupancy, as defined in Section 202, without a corresponding change of occupancy classification shall comply with Section 901.2.

901.2 Change in occupancy with no change of occupancy classification.

A change in occupancy, as defined in Section 202, with no change of occupancy classification shall not be made to any structure that will subject the structure to any special provisions of the applicable International Codes , including the provisions of Sections 902 through 911, without the approval of the code official . A certificate of occupancy shall be issued where it has been determined that the requirements for the change in occupancy have been met.

CHANGE OF OCCUPANCY. A change in the purpose or level of activity within a building that involves a change in application of the requirements of this code.

 

[RLGA]

mtlogcabin: Good point. My comments were specifically addressing the change in occupancy classification (i.e. it wasn't an assembly occupancy [Group A] before and is now an assembly occupancy).

I wish they would change it to "Change in Use or Occupancy." Thus, a large 750 sq. ft. office (Group B) that changes into a conference room (i.e. the use has changed, but it is still a Group B) would be considered a "Change in Use" (or "Change in occupancy with no change of occupancy classification" per current IEBC language).

 

[Paul Sweet]

I can get even more confusing when the code has changed the occupancy classification of the use. For instance, colleges were originally A-4 (assembly) under BOCA, then became E (educational), and finally became B (business).