Determining Room Capacity

Event planners often have trouble determining how many guests can fit into a specific room. I have been in too many situations, especially dinners, where guests are cramped or there is a safety issue because aisles are not wide enough for egress. As luck would have it, there are guidelines, thanks to the Convention Industry Council Manual and the expertise of Catering Managers. Here they are.

• Standup reception. 9 – 10 sq ft (.84 - .93 sq m) per person.
• Theater seating (less than 60 people). 12 – 13 sq ft (1.1 – 1.2 sq m) per person. This allows at least 24 in. (61 cm) of space between rows, which is the most comfortable.
• Theater seating (60 to 300 people). 11 – 12 sq ft (1.0 – 1.2 sq m) per person.
• Theater seating (more than 300 people). 10 – 11 sq ft (.93 – 1.0 sq m) per person.
• Schoolroom general. 17 – 22 sq ft (1.6 – 2.9 sq m) per person. This allows for rectangular tables that are 6 or 8 ft (1.8 or 2.4 m) long and 18 in. (46 cm) wide, with 2 ft (.61 m) per person and 3.5 ft (.91 m) between tables as a minimum for optimum comfort.
• Banquet seating (60 in. or 152 cm diameter rounds). 13.5 sq ft (1.25 sq m) per person for optimum comfort for eight persons at the table. A 12 ft center-to-center separation is best for maximum comfort and safety.
• Banquet seating (66 in. or 168 cm diameter rounds). 13.5 sq ft (1.25 sq m) per person for optimum comfort for nine persons at the table. A 12.5 ft center-to-center separation is best for maximum comfort and safety.
• Banquet seating (72 in. or 183 cm diameter rounds). 13.5 sq ft (1.25 sq m) per person for optimum comfort for 10 persons at the table. A 13 ft center-to-center separation is best for maximum comfort and safety.

Note that these numbers do not allow for any staging or other elements such as décor in the venue. The area occupied by these extra event elements must be taken into consideration if an accurate estimate of capacity is to be determined. For ease of illustration, let us assume that an event will have a stage against the long wall of a rectangular room. The calculation for capacity is therefore given by the following formula:

Capacity     =       Useable area        
                          Area per person        

                   =   (Room length x Room depth) – (Room length x Stage depth)
                                                      Area per person

Likewise, the area used by any other décor elements or hard impediments must be taken into account and deducted from the total useable area. This method of course assumes that the area behind the stage or other impediment is unusable area. The figure below is a graphical representation of this methodology. In this case, the room length is 100 ft, room depth 80 ft, stage width 20 ft, and stage depth 16 ft.

Determination of the Useable Area of an Indoor Venue

In this example, the total room area is 8000 sq ft (i.e. 100 ft x 80 ft) but the useable area is only 6400 sq ft (i.e. 8000 sq ft – 1600 sq ft) where 1600 sq ft represents the unusable area occupied by the stage and the area behind the front of the stage that runs the length of the room. Assuming that this event is to be a dinner, then the room capacity in this example would be 592 persons (i.e. 8000 sq ft/13.5 sq ft per person) if there were no stage, and 474 persons (i.e. 6400 sq ft/13.5 sq ft per person) if the stage were to be used in the location drawn.

It's always best to double check all calculations for room capacity particuarly when you expect to be close to capacity or when there are numerous other elements in the mix such as buffet tables, staging, or decor.