What is a corridor?

[Spector_51]

I know right! sounds simple enough. Been in building code enforcement for 25 year now so wait for it please!

Definition from ICC 2012 CORRIDOR. An enclosed exit access component that defines and provides a path of egress travel.

Now for some context. For 25 years I have thought that when you have a hallway (purposely avoiding the term corridor for this context) where an occupant is led by design (think of the base of a funnel) to a single exit. you have a corridor. I am raising with due to the word enclosed in the definition. Getting right to the matter, does enclosed mean "all six sides". Or better yet, if I have a large room, say an office cube farm, that is connected to said "hallway", and the hallway leads to an exit stair, however, said room is not separated from the hallway with doors, is this still a corridor.

For purposes of this discussion this is a sprinklered B use, therefore the fire rating is not required.

this question is being raised in the application of Section 1018.5.

 

[cda]

If you have this condition

For purposes of this discussion this is a sprinklered B use, therefore the fire rating is not required.

Than if you have a corridor or not does not matter

Will have to look at 1018.5

 

[cda]

Since you have a non rated corridor
I am thinking it does not apply!!’



1018.5Air movement in corridors.
Corridors shall not serve as supply, return, exhaust, relief or ventilation air ducts.

Exceptions:

1. 1.Use of a corridor as a source of makeup air for exhaust systems in rooms that open directly onto such corridors, including toilet rooms, bathrooms, dressing rooms, smoking lounges and janitor closets, shall be permitted, provided that each such corridor is directly supplied with outdoor air at a rate greater than the rate of makeup air taken from the corridor.
   
   
2. 2.Where located within a dwelling unit, the use of corridors for conveying return air shall not be prohibited.
   
   
3. 3.Where located within tenant spaces of 1,000 square feet (93 m2) or less in area, utilization of corridors for conveying return air is permitted.
   
   
4. 4.Incidental air movement from pressurized rooms within health care facilities, provided that the corridor is not the primary source of supply or return to the room.
   

 

[ADAguy]

Back in the day, you have what we now call "open office" large areas (rooms?) with cubicles no more than 60" tall.
Cubes interconnected by paths between them (corridors?) that don't extend to the ceiling and yes fully sprinklered.

 

[mtlogcabin]

Fire rated or not, sprinklers or not, the section applies to all corridors. The intent of the section is to keep smoke from migrating from the adjacent rooms into the corridor thus making it useless as a means of egress

1018.5Air movement in corridors.
Corridors shall not serve as supply, return, exhaust, relief or ventilation air ducts.

 

[cda]

Fire rated or not, sprinklers or not, the section applies to all corridors. The intent of the section is to keep smoke from migrating from the adjacent rooms into the corridor thus making it useless as a means of egress

But

If the corridor is not required to be rated

It is not required to have rated doors

It is not required to have any doors

So with no doors, the smoke and fire is going to sneak into the non rated corridor

 

[mtlogcabin]

If the corridor is not required to be rated

It is not required to have rated doors

It is not required to have any doors Then it is not a corridor by definition because it is not enclosed. BTW IMHO a corridor is enclosed when it has a floor, two walls, a ceiling and doors separating it from the rooms it serves. It is not required to have doors on the ends to require a fire rating. The required fire rating is to protect the occupants of a corridor from fire in the adjoining rooms
So with no doors, the smoke and fire is going to sneak into the non rated corridor

 

[cda]

Agree

 

[Spector_51]

all i want to know is if there are not six sides to this entity, whatever we want to call it- is it still a corridor?

the situation is in this building there is no drop ceiling and no plan to duct return air. designer show transfer grills from adjoining and connected space to this "corridor".

They are seeking a code modification to 1018.5 the basis of which is the definition of corridor is not met as there is no door or separation between the "Cube farm" and the hallway.

I say the space (hallway) should be identified first as either a corridor or not and then the rest of the code applies.

I also say it is a corridor.

I equate this to an atrium where you have an unprotected floor opening connecting two stories. This condition is still an atrium however most of the code sections in atriums do not apply to two story atriums.

I really wish to focus this forum as my original post suggests.

I seem to remember a different definition of corridor that was more focused on the single path of egress matter and less on the enclosure issue


Many thanks.

 

[cda]

all i want to know is if there are not six sides to this entity, whatever we want to call it- is it still a corridor?

the situation is in this building there is no drop ceiling and no plan to duct return air. designer show transfer grills from adjoining and connected space to this "corridor".

They are seeking a code modification to 1018.5 the basis of which is the definition of corridor is not met as there is no door or separation between the "Cube farm" and the hallway.

I say the space (hallway) should be identified first as either a corridor or not and then the rest of the code applies.

I also say it is a corridor.

I equate this to an atrium where you have an unprotected floor opening connecting two stories. This condition is still an atrium however most of the code sections in atriums do not apply to two story atriums.

I really wish to focus this forum as my original post suggests.

I seem to remember a different definition of corridor that was more focused on the single path of egress matter and less on the enclosure issue


Many thanks.

There is the exit passage way.
Which is normally a one way exit

 

[cda]

But if you say it is s non rated corridor and they meet the requirements for non rated

To me end of story

Even though some of it looks like a corridor

Not sure if I am missing something

 

[ADAguy]

hmmmm ??

 

[mtlogcabin]

Or better yet, if I have a large room, say an office cube farm, that is connected to said "hallway", and the hallway leads to an exit stair, however, said room is not separated from the hallway with doors, is this still a corridor.

2012 IBC
If the "hallway" serves more than 30 people then Table 1018.1 requires you to install doors thus turning your "hallway" into a corridor.

as there is no door or separation between the "Cube farm" and the hallway.

Then why do you need transfer grilles?

designer show transfer grills from adjoining and connected space to this "corridor".

 

[mtlogcabin]

What is a corridor?

According to a UBC instructor I had many years ago a corridor is similar to leading cows to slaughter. Once the people enter the corridor they are being led by design down a specific path with little or no options for escape. So protection of the corridor from fire and smoke is essential.

 

[RLGA]

If the "hallways" or "corridors" are created by moveable cubicle partitions or permanent low-wall partitions, then they are neither "hallways" nor "corridors" but aisles. Thus, the requirements for corridors never factor into the situation. However, the requirements of Section 1017 for aisles do come into play.

 

[Sifu]

I have a job where the 2nd floor corridor is supposed to be rated as a non-sprinkled corridor. It is open at the end where the 2 story stair connects. The remainder of the openings into the corridor (tenant spaces) are covered by doors. I got a little hung up on the word "enclosed" too. But after reading the commentary, which indicates one of the reasons for the "enclosed" part is due to sensory perception, I decided the open end wasn't a critical part of the enclosure. So if a user can't see what is happening on the other side [of a corridor, hallway etc], then a higher level of protection is required as a "corridor", thus the rating requirement. Since a 2-story open stair is allowed by code I don't see the requirement to enclose the end of the corridor at the steps. But I understand the confusion, and I am not 100% certain of my evaluation.

 

[Mr. Inspector]

If there are waiting rooms and rest rooms with no doors open to a corridor they would be part of the corridor so when you need a one hour wall it needs to include going around these rooms too. So if you have a room that is open at the end of a required rated corridor that whole room would need 1 hour walls or a rated door.

 

[rgrace]

Fire rated or not, sprinklers or not, the section applies to all corridors. The intent of the section is to keep smoke from migrating from the adjacent rooms into the corridor thus making it useless as a means of egress

I just wanted to bring this back up. Thanks mtlogcabin ! This statement about 1018.5 is brutally accurate but appears to be getting lost in this string. Rated, not rated, sprinklered or not, combustible or not, high-rise, low-rise, mid-rise, multi-tenant, single-tenant (greater than 1,000 sq.ft.), none of it matters. The intent of this section is to keep our egress means free from filling with smoke by means of the air distribution systems installed in the building.

 

[cda]

I just wanted to bring this back up. Thanks mtlogcabin ! This statement about 1018.5 is brutally accurate but appears to be getting lost in this string. Rated, not rated, sprinklered or not, combustible or not, high-rise, low-rise, mid-rise, multi-tenant, single-tenant (greater than 1,000 sq.ft.), none of it matters. The intent of this section is to keep our egress means free from filling with smoke by means of the air distribution systems installed in the building.

But if not rated

Doors are not required

So smoke will sneak into all areas

 

[CityKin]

4,500 SF unsprinklered dentist office, exam rooms have no doors..... Is this a corridor? Does it need to be rated if it serves an occupant load over 30? I am never sure how to define "corridor"

 

[CityKin]

Sorry, I tried to post an image. I thought I was a sawhorse and could post images. I pay every year ..

 

[cda]

Sorry, I tried to post an image. I thought I was a sawhorse and could post images. I pay every year ..

Have to use real money

Hit your profile and

Hit upgrade and see what it says

Plus send Jar a message to look at your account

 

[classicT]

Sorry, I tried to post an image. I thought I was a sawhorse and could post images. I pay every year ..

Please check out this post.

https://www.thebuildingcodeforum.com/forum/threads/sawhorses-and-supporters-please-read.28239/

 

[cda]

4,500 SF unsprinklered dentist office, exam rooms have no doors..... Is this a corridor? Does it need to be rated if it serves an occupant load over 30? I am never sure how to define "corridor"

Are two exits required??

If yes, without seeing the picture, you have a corridor

Are you sure on occupant load,,, seems high