IEBC Dead end corridor length

[manifold]

I am working on a remodel to an existing building under the 2015 IEBC. Change of use, unsprinklered. It is necessary to revise the layout such that we are creating 2 new dead end corridors that are between 20 feet and 35 feet long. In the existing layout one of these corridors was 20 feet long to a dead end, the other continued to an exit (the exit is not required, other existing exits satisfy requirements).

By my reading of IEBC Section 805.6, 35 foot dead end corridors are allowed. There is no distinction as to whether or not this applies to new or existing corridors (there is a distinction between new, existing, and extended corridors in the subsequent exceptions). There is some debate in the office with others suggesting that the 35 foot rule only applies to existing corridors and new would have to comply with the 20 foot length called out in the IBC.

Is it an accurate interpretation to proceed with a new 35 foot dead end corridor?

 

[RLGA]

Since this is a change of use, you have to comply with the requirements for Change of Occupancy as stated in IEBC Section 1001.2.1. IEBC Section 1005 on Means of Egress references IEBC Section 1012.

IEBC Section 1012.4 addresses general means of egress, and requires establishing the hazard category for the change per IEBC Table 1012.4. If the change is to a more hazardous category, then compliance with IBC Chapter 10 is required, except that dead end corridors are permitted to comply with IEBC Section 805.6 per Exception 6.

However, if the change is to an occupancy of equal or lesser hazard, then compliance with IEBC Section 905 (which references Section 805) applies to corridors that remain unalterd. Thus, Section 805.6 would still apply, but the corridors must comply with all applicable requirements of IEBC Sections 805 and 905. Newly constructed corridors must comply with IBC Chapter 10--there is no exception to allow IEBC Section 805.6.

 

[Francis Vineyard]

The intent that it is for existing is additionally provided by Sections 7004.1 and 801.3

 

[manifold]

However, if the change is to an occupancy of equal or lesser hazard, then compliance with IEBC Section 905 (which references Section 805) applies to corridors that remain unalterd. Thus, Section 805.6 would still apply, but the corridors must comply with all applicable requirements of IEBC Sections 805 and 905. Newly constructed corridors must comply with IBC Chapter 10--there is no exception to allow IEBC Section 805.6.

Thanks. The change of use is to an equal hazard category for means of egress (to B from F-1).

The intent that it is for existing is additionally provided by Sections 7004.1 and 801.3

Section 801.3 Exception 3 states that new dead end corridor shall comply with Section 805.6. Though Section 1012.4.2 supersede this.

Thanks for your input!

 

[Francis Vineyard]

manifold you're welcome and thanks for your participation on this forum for clarification. However my reference was to the answer whether the 35 ft. applies to new construction.

Perhaps the following two (2) proposed code change will help others as to intent.