Unoccpied accesssory areas

[Mech]

2006 IBC / IMC

Is there a definition of "unoccupied accessory areas" in the IMC?

Per the IMC, required outdoor ventilation is based on net floor area (footnote 'a' in Table 403.3), which by definition excludes wall thickness and unoccupied accessory areas. I did not see a definition in the IMC for "unoccupied accessory area," so I turned to the IBC.

Definition from the IBC: FLOOR AREA, NET. The actual occupied area not including unoccupied accessory areas such as corridors, stairways, toilet rooms, mechanical rooms and closets.

So corridors do not require outdoor ventilation (by the IBC's definition), but there is an outdoor ventilation rate given in the IMC table. Hmmm . . .

 

[peach]

those areas will be occupied by someone at some time..

Certainly you are not thinking toilet rooms don't need ventilation.

Natural or mechanical, you need to move air thru these areas.

Looks like the ICC correlating committee maybe missed something

 

[Mech]

Fear not, the toilet rooms will be provided with mechanical ventilation. I just stumbled upon the somewhat conflicting info for corridors, and I guess toilet rooms also.