Fire Separation Distance at Irregular Lot Line

[MKALLAY]

I am looking at a project where a lot line along one side of a building jogs so that a portion of the wall will be less that 10' from the line, but the remainder of the wall is greater than 10' from the line (measured perpendicular from the wall). For the construction type IIb, a 1 hour fire resistance rating is required when the fire separation distance is less than 10'. Does the required fire resistance rating apply to the entire wall in that plane, or need it only apply to the portion of the wall that has less than 10' fire separation distance?

 

[Yankee Chronicler]

It applies only to the portion of the wall that is within 10 feet of the property line.

 

[walker.t]

Does the required fire resistance rating apply to the entire wall in that plane, or need it only apply to the portion of the wall that has less than 10' fire separation distance?

This thread has discussion on the same topic which may be of interest to you:

Table 602 - Rating required for entire wall?

I have a IIB building in which a portion of the exterior wall has a fire separation distance of less than 10 feet. Am I correct thinking the portions of the exterior wall where the fire separation distance is less than 10' require a 1 hour rating where the portion of the wall with a FSD greater...

www.thebuildingcodeforum.com

 

[Paul Sweet]

It's probably easiest to fire rate the entire wall instead of having to deal with 2 different types of construction and making sure they are actually built in the right place.

 

[MKALLAY]

It's probably easiest to fire rate the entire wall instead of having to deal with 2 different types of construction and making sure they are actually built in the right place.

I would agree - but in this case, it is a very long wall with a very short portion that requires the rating, and different walltype conditions along the entire length. But generally yes, it is simpler from a constructability standpoint to keep the like - portion of construction consistent.

Thank you all above for your replies!