I have a somewhat basic (dumb?) question about area calculations -
Reading through the 2009 IBC it defines building area as:
I ask because we frequently run our calculations using BOMA (exterior face / centerline of party walls) and the additional thickness of exterior walls will create a variation in the occupancy allowed in the building. I know the developers / property owners want BOMA calcs for rental reasons but it seems that for code purposes that is not the correct way to measure.
Am I completely off base here or have we been doing it incorrectly?
Thanks
Reading through the 2009 IBC it defines building area as:
If I'm reading this correctly - area calculations for code purposes should be calculated from the interior face (finish face or core face?) of exterior walls correct? If this is true - how to party walls get measured?502.1AREA, BUILDING. The area included within surrounding exterior walls (or exterior walls and fire walls) exclusive of vent shafts and courts. Areas of the building not provided with surrounding walls shall be included in the building area if such areas are included within the horizontal projection of the roof or floor above.
1002.1
FLOOR AREA, GROSS. The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.
FLOOR AREA ,NET. The actual occupied area not including unoccupied accessory areas such as corridors, stairways, toilet rooms, mechanical rooms and closets.
I ask because we frequently run our calculations using BOMA (exterior face / centerline of party walls) and the additional thickness of exterior walls will create a variation in the occupancy allowed in the building. I know the developers / property owners want BOMA calcs for rental reasons but it seems that for code purposes that is not the correct way to measure.
Am I completely off base here or have we been doing it incorrectly?
Thanks