Smoke and Heat Vents

[Mech]

2009 IBC

According to Section 910.2.1, "Buildings or portions thereof used as a Group F-1 or S-1 occupancy having more than 50,000 sq. ft. in undivided area" need smoke and heat vents.

Please define "undivided area." Are fire rated walls / partitions / barriers or smoke barriers / partitions needed to create a "divided area" or are non-rated assemblies good enough?

The proposed work will place a 3,445 sf S-1 addition onto an existing 68,529 sf B and S-2 building along an existing unrated wall with a proposed unrated door opening and I am trying to determine if smoke and heat vents are required.

Thanks in advance.

 

[peach]

well, probably not rated.. just get rid of open areas or plan for the vents.

Having said that, I'm guessing many plan reviewers miss this and leave it for the poor field inspector... who becomes the bad guy.

You go, bad guy.

 

[RLGA]

If it doesn't state that any type of fire-resistive assembly or smoke partition is required, then I would interpret this to mean any type of physical separation whether it is rated or non-rated. The intent is to prevent smoke from spreading over the entire space, and typical wall construction can prevent this from happening by confining the smoke to a smaller area.