Question re: automatic sprinkler system requirements: IBC 903.2.11.1 Floors without openings

[palikona]

Thanks for the help in advance. I am designing a single story commercial (6,000 sf footprint) with full basement below. Per IBC 903.2.11.1, it appears I need to provide an automatic sprinkler system because the basement is over 1500 sf. I was thinking to see if exception 1 could be met, but I wanted to make sure I’m reading it correctly. So my question is: in order to take exception 1, the basement would need to have rated exit stairs spaced 50 linear feet apart max, correct? See the section below:

[F] 903.2.11.1 Stories Without Openings

An automatic sprinkler system shall be installed throughout all stories, including basements, of all buildings where the floor area exceeds 1,500 square feet (139.4 m2) and where the story does not comply with the following criteria for exterior wall openings:

1. Openings below grade that lead directly to ground level by an exterior stairway complying with Section 1011 or an outside ramp complying with Section 1012. Openings shall be located in each 50 linear feet (15 240 mm), or fraction thereof, of exterior wall in the story on not fewer than one side. The required openings shall be distributed such that the lineal distance between adjacent openings does not exceed 50 feet (15 240 mm).

 

[steveray]

I don't think the stair needs to be rated...

 

[palikona]

I don't think the stair needs to be rated...

Ah ok. But am I reading it correctly that if stairs cannot be provided every 50 linear feet, this exception cannot be taken and I need to include an automatic sprinkler system? Thanks.

 

[classicT]

Ah ok. But am I reading it correctly that if stairs cannot be provided every 50 linear feet, this exception cannot be taken and I need to include an automatic sprinkler system? Thanks.

Correct. The basement walls must have exterior stairs or ramp every 50-ft.

 

[palikona]

Thanks for confirming.

 

[Paul Sweet]

The openings are only required on one side, unless the opposite side of the building is farther than 75 feet from the side with openings.

You don't need a stair or ramp for each door. You can have several doors opening into an areaway with a single ramp or stair out of the areaway as long as there is another means of egress from the basement, such as an interior stair.

 

[classicT]

The openings are only required on one side, unless the opposite side of the building is farther than 75 feet from the side with openings.

You don't need a stair or ramp for each door. You can have several doors opening into an areaway with a single ramp or stair out of the areaway as long as there is another means of egress from the basement, such as an interior stair.

Correct.... that is clarified in the subsequent code sections provided as follows.

[F] 903.2.11.1.2 Openings on One Side Only​

Where openings in a story are provided on only one side and the opposite wall of such story is more than 75 feet (22 860 mm) from such openings, the story shall be equipped throughout with an approved automatic sprinkler system, or openings shall be provided on not fewer than two sides of the story.​

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[F] 903.2.11.1.3 Basements​

Where any portion of a basement is located more than 75 feet (22 860 mm) from openings required by Section 903.2.11.1, or where walls, partitions or other obstructions are installed that restrict the application of water from hose streams, the basement shall be equipped throughout with an approved automatic sprinkler system.​

​

I would note that it says "where any portion"; because of that verbiage, I would use a 75-radius from the required openings. This would significantly decrease the width of the space unless many openings were provided.

 

[Paul Sweet]

You're right. I saw the 75 ft. in both, and read right over "opposite wall" (above grade) and "any portion" (basement)

 

[admiralArchArch]

Correct.... that is clarified in the subsequent code sections provided as follows.

[F] 903.2.11.1.2 Openings on One Side Only​

Where openings in a story are provided on only one side and the opposite wall of such story is more than 75 feet (22 860 mm) from such openings, the story shall be equipped throughout with an approved automatic sprinkler system, or openings shall be provided on not fewer than two sides of the story.​

​

[F] 903.2.11.1.3 Basements​

Where any portion of a basement is located more than 75 feet (22 860 mm) from openings required by Section 903.2.11.1, or where walls, partitions or other obstructions are installed that restrict the application of water from hose streams, the basement shall be equipped throughout with an approved automatic sprinkler system.​

​

I would note that it says "where any portion"; because of that verbiage, I would use a 75-radius from the required openings. This would significantly decrease the width of the space unless many openings were provided.

Bringing this back from the past. What constitutes an "opening" in this paragraph?

 

[mtlogcabin]

[F] 903.2.11.1.1 Opening dimensions and access.
Openings shall have a minimum dimension of not less than 30 inches (762 mm). Access to such openings shall be provided for the fire department from the exterior and shall not be obstructed in a manner such that fire fighting or rescue cannot be accomplished from the exterior.

A window or a panel/door/hatch that would be label Fire Department Access that allows the FD to enter that area.