Common Path of Egress Travel

[bwswede]

All,

I am hoping to get an opinion from the knowledge base here. I am looking at a 4 story building that has a ground level A-2 and 3 levels of R-2 above it. The 3 levels of R-2 are arranged like a townhouse in that each of the 3 dwellings is 3 stories tall and is accessed from the second floor of the building. I am reading the Code in two different ways.

The first way has me believing that the CPET starts on the 3 floor of the dwelling and ends just outside the dwelling's main entry on the building's second floor. At which point the design has an exit vertical exit enclosure at each end of the hall servicing the dwellings. (1014.3, 1014.3 Ex. 4)

The second way I read the code has me believing that the CPET does not apply to spaces that are only required to have one exit, such as the interior of a dwelling, and that the CPET starts just outside the main door into the unit. (From the IBC commentary, the definition for "Common path" indicates the provisions are only applicable when access to two or more exits is required.) Since only one exit is required from the dwelling does this mean the CPET starts outside the entry door of the dwelling?

I hope my question is clear, if not I'll try to elaborate.

TIA,

BWSwede

 

[mtlogcabin]

IBC 2012

1021.2.3 Single-story or multiple-story dwelling units.

Individual single-story or multiple-story dwelling units shall be permitted to have a single exit within and from the dwelling unit provided that all of the following criteria are met:

1. The dwelling unit complies with Section 1015.1 as a space with one means of egress and

2. Either the exit from the dwelling unit discharges directly to the exterior at the level of exit discharge, or the exit access outside the dwelling unit’s entrance door provides access to not less than two approved independent exits.

015.1 Exits or exit access doorways from spaces.

Two exits or exit access doorways from any space shall be provided where one of the following conditions exists:

1. The occupant load of the space exceeds one of the values in Table 1015.1.

Exceptions:

1. In Group R-2 and R-3 occupancies, one means of egress is permitted within and from individual dwelling units with a maximum occupant load of 20 where the dwelling unit is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2.

2. Care suites in Group I-2 occupancies complying with Section 407.4.3.

2. The common path of egress travel exceeds one of the limitations of Section 1014.3.

3. Where required by Section 1015.3, 1015.4, 1015.5, or 1015.6.

Table 1014.3 allows 125 ft commaon path of travel in a sprinklered building

 

[bwswede]

MT,

Thank you for the reply.

Thank you for confirming the dwelling only needs one exit and that the dwelling needs Exit Access to two approved independent exits.

I still have a question regarding the CPET. Does it start at a remote corner in the top floor of the dwelling and stop at the dwelling's front door, or does it start beginning of the Exit Access just outside the front door of the dwelling? According to the commentary I read spaces only requiring one exit (the dwelling) do not need to calculate CPET.

Thanks again,

BWSwede

 

[cda]

From rlga

http://www.specsandcodes.com/articles/the%20code%20corner%20no.%2029%20-%20travel%20distance.pdf

 

[FM William Burns]

From the Building Code:

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.

 

[steveray]

CPET starts at the most remote point of the entire building or dwelling within the building....Example....Back corner of remote bath or bedroom to exterior less than or equal to 125' in a sprinklered building...Or 2 exits required.

 

[bwswede]

You guys are awesome. Thank you for the replies.

BWSwede3

 

[mtlogcabin]

Thank you for confirming the dwelling only needs one exit and that the dwelling needs Exit Access to two approved independent exits.

You did not understand the code as written

The individual dwelling units must meet the CPET of 125 ft in a sprinkled building in order to have a single exit from the dwelling unit.

 

[Francis Vineyard]

http://www.koffel.com/training/Handouts/Significant_Means_of_Egress_Changes_to_2012_IBC_and_2012_NFPA_101-webinar-Handout.pdf

 

[bwswede]

The individual dwelling units must meet the CPET of 125 ft in a sprinkled building in order to have a single exit from the dwelling unit.

MT. Yes, I understand that it needs to have a CPET of less that 125' (sprinklered and under 20 occupants) for a unit to have one exit. Thanks for checking

FV. Nice diagrams. Further helps to confirm my understanding of two exits per floor.

Thanks again,

BWSwede