Common Path of Travel

[Coug Dad]

The commentary to the 2009 IBC regarding common path of travel was dramatically changed to include the following:

Common path of egress travel does not apply to stories or spaces with one exit. See Section 1021.2 for travel limitations for

one, two and three story buildings and Section 1015.1 for spaces with one exit. The definition for “Common path”

indicates the provisions are only applicable when access to two or more exits is required.

This paragraph was not in the earlier versions of the commentary. I know commentary is not code, but it can carry a lot of weight since it is published by ICC.

This would imply that a room or space that only requires one exit access based upon occupant load is not subject to common path of travel requirements. For example, if I have an office space of 4,900 square feet measuring 49 feet by 50 feet, I could have a common path of travel of 150 feet or more. This new section of commentary would infer that the typical 75 / 100 foot of common path of travel would not apply.

This seems to conflict with 1015.1 which requires two exits or exit access doorways when either the occupant load exceeds Table 1015.1 or the common path of travel is exceeded. This seems to be a great conflict.

Can anyone help!

 

[mtlogcabin]

The commentary just clarifies what the code already states. A single exit is only permitted when the "occupant load AND the travel distance" are met. Table 1021.2 limits travel distances from 25 ft to a maximum 100 ft depending on the occupancy type and OL. The distances are consistant with 1014.3

 

[Coug Dad]

The commentary just clarifies what the code already states. A single exit is only permitted when the "occupant load AND the travel distance" are met. Table 1021.2 limits travel distances from 25 ft to a maximum 100 ft depending on the occupancy type and OL. The distances are consistant with 1014.3

I agree that is what it used to say. However, the 2009 commentary states that common path of travel does not apply to rooms that require only one exit based upon occupant load alone.

 

[AegisFPE]

I agree, the commentary could have been more clear. Perhaps the authors are trying to describe that CPT does not apply in the sense that it would not come into play given the limited travel distances in Table 1021.2.

From 1021.2:

Occupancies shall be permitted to have a single exit in buildings otherwise required to have more than one exit if the areas served by the single exit do not exceed the limitations of Table 1021.2.

Therefore, where the travel distance (say 150') exceeds that in the table (say limited to 100') then two exits would be triggered, as would common path of travel provisions.

 

[RLGA]

For Section 1021.2, it is because it refers to Table 1021.2, which has its own travel distance criteria. If you'll notice, the travel distance stated in the table is fairly close, if not identical, to the CPET requirements.

For Section 1015.1, the Commentary is not clear and I think it could have been worded much better. When a space that is allowed to have one exit, then CPET does not technically apply; HOWEVER, if the distance to an exit exceeds the CPET distance per Section 1015.1, Item 2, then it is no longer a space with one exit since two are now required. In reality, CPET does factor in the design of each space, even if it is only to see if the maximum distance is exceeded in order to determine if two exits need to be provided.

 

[brudgers]

I agree that is what it used to say. However, the 2009 commentary states that common path of travel does not apply to rooms that require only one exit based upon occupant load alone.

ICC makes a change for the sake of making a change. Confusion ensues. Film at 10.

 

[mtlogcabin]

COMMON PATH OF EGRESS TRAVEL. That portion of exit access which the occupants are required to traverse before two separate and distinct paths of egress travel to two exits are available. Paths that merge are common paths of travel. Common paths of egress travel shall be included within the permitted travel distance.

The commentary is correct because a single exit building or space does not provide two exits. In order to have a common path of egress travel by definition you first need two exits.

Ther are no CPOET in a single exit building/space

 

[Coug Dad]

mtlogcabin,

If you are correct, then I can have an office space that is 49 feet by 100 feet and a "common path of travel" within the space of over 150 feet?

 

[permitguy]

No. You'd be violating other sections of the code (1021.1, 1021.2). Once those sections establish the requirement for a second exit, then CPOET does apply.

 

[mtlogcabin]

If you are correct, then I can have an office space that is 49 feet by 100 feet and a "common path of travel" within the space of over 150 feet?

You will only have a common path of travel if you have two exits to choose from within the distance limitation.

If your office only has one exit then no you can't because your travel distance exceeds 75 ft (100 ft if sprinkled) see Table 1021.2

MAXIMUM OCCUPANTS (OR DWELLING UNITS)

PER FLOOR AND TRAVEL DISTANCE

A, Bd, Ee, Fd, M, U, Sd 49 occupants and 75 feet travel distance

 

[High Desert]

Quit reading the so much into the commentary. The CPET and buildings and spaces with one exit provisions haven't changed.

 

[Builder Bob]

I see the issue with Spaces with one exit......

I think the issue of when can a single exit serve a story has been greatly enhanced.

 

[north star]

& & & &



Coug Dad,

Which is the more restrictive application of the "letter of the

code" ( refer to Section 102.1, `09 IBC )?

& & & &

 

[mtlogcabin]

I see the issue with Spaces with one exit......

What issue? All spaces are required to have two exits

1021.1 Exits from stories.

All spaces within each story shall have access to the minimum number of approved independent exits as specified in Table 1021.1 based on the occupant load of the story

Exceptions

2. As modified by Section 1021.2. This has been covered

5. Within a story , rooms and spaces complying with Section 1015.1 with exits that discharge directly to the exterior at the level of exit discharge , are permitted to have one exit .

Exception 1 OL same as Table 1021.2

Exception 3 sends you to the CPOT requirements which will require 2 exits when the travel distance limits are exceeded.