Quick Calculations

Calculating the Capacity of Function Rooms

Have you ever stood in a break out room with the Venue’s meeting space capacity chart in hand and thought, “There’s no way 125 people can fit in here theatre style”, you know how important it is to be able to independently determine the number of attendees that can be seated comfortably in any given function room. Fortunately it is relatively easy to do that.

Calculate how much space you have to work with after taking columns and other obstructions into consideration. – Measure the room to determine the shortest distances that form the room’s length and width. E.g. The Venue may show the dimensions of a room to be 130’ x 60’. But if you factor in the columns along the back wall of the room and the storage areas along the sides of the room the “clear meeting area” may be significantly less.
Once you have the clear meeting area, follow these formulas to figure out the true capacity of the room for the 3 most common types of seating – theatre style, classroom style and banquet. The objective of all 3 formulas is to ensure that every attendee has an unobstructed view of the screen or speaker, easy access to his or her seat, and sufficient elbow room.

Note: To maximize capacity, arrange for the front of the room to be on the narrow wall.

Quick Calculations
To quickly figure out how large a room you need for a set up, multiply the number of people by the appropriate square footage per person from the formulas below. To determine if a certain meeting room can accommodate a desired setup, divide the room’s total square footage by the appropriate square footage per person from the formulas below.

Theatre Style
12 square feet per person for groups of less than 60 people
11 square feet per person for groups of 60 to 300 (the most common size breakout session)
10 square feet per person for groups of more than 300 people

Classroom Style
22 square feet per person for groups of less than 60 people
20 square feet per person for groups of 60 to 300 people (the most common size breakout session)
17 square feet per person for groups of more than 300 people

Banquet Style
13.5 square feet per person

Exhibit Space
Number of booths x booth length x booth width x 2. (multiply by 2 to allow for lost space in corners and aisles)

Conference Style or Hollow Square
30 square feet per person

U Shape
35 square feet per person

Note: The smaller the room or more square the room is, the greater the square footage needs per person. In a smaller or square room, there is more wasted space per person in the front, back and sides of the room.

Theater Style

Theatre Style Formula

Most Venues offer meeting room chairs that are 20” front to back and between 17.5” and 18.5” wide. The standard used by the majority of facilities is to place the chairs immediately adjacent to each other and to use one chair’s length as a measuring stick between rows. When these standards are used, it’s very difficult to fully utilize the seating area since attendees do not want to climb over each other to reach an empty seat or sit shoulder to shoulder with their neighbors. The result – chairs remain unoccupied. The following formula adds 2-3 inches to the above standards, thereby increasing comfort and allowing greater percentage of the seating area to be utilized.

Step 1: Determine the number of rows that can be accommodated.
Take the clear room length and subtract the space between the screen and the front row (normally two times the screen height) and the space between the back wall and the back row (minimum of 4 feet).
Note: Two times the screen height is a standard that allows a person to view the entire screen comfortably. If you don’t know the screen height, subtract 20% from the clear length of the room.
Then divide by the distance between rows, measured from chair back to chair back (3.58 feet or 43 inches).
Round the resulting figure down to the nearest full row.
Note: Do not exceed more than 30 feet of continuous seating before placing aisles.

E.g. 100 (length of room) – 20 (2x screen height) – 4 (distance from back wall) = 76 (usable room length).
76 ÷ 3.58 (distance between rows) = 21.2 rows, rounded down to 21 rows.

Step 2. Determine the number of chairs that can be set in each row.
Take the clear room width and subtract space for aisles (normally 15%)
Divide by the distance between chairs, measured from chair centre to chair centre (1.83 feet or 22 inches).
Round the resulting figure down to the nearest chair.

E.g. 75 (width of room) – 11.25 lost to aisles (15% of 75) = 63.75 (usable room width)
63.75 ÷ 1.83 (distance between chairs) = 34.84, rounded down to 34 chairs.

Step 3: Multiply the number of rows by the number of chairs in each row.
E.g. 21 (rows) x 34 (chairs) = 714 people that can be comfortably accommodated in the room.

Note: Seats from which the view of the screen or speaker is obscured should be removed. Seats located less than a 30-degree angle to the screen also should be removed since the viewing angle is too acute to provide easy reading of the projected material.

Classroom Style

Classroom Style Formula

Most Venues will offer 6 foot and/or 8 foot tables that are 18 inches wide for their classroom style setups. To determine the space between rows, the majority of facilities use a 6 foot table as a measuring stick. A 6 foot table is placed at a 90 degree angle to the first table in the room. The front of the first table is matched up with one end of the 6 foot and the back of the second table is matched up with the other end of the 6 foot table. The result is a 3 foot gap between the two tables [(6 feet – (2x18 inches)]. This standard is perfect for proper spacing between rows.

The majority of facilities will seat 3 people at a 6 foot table or four people at an eight foot table (allowing 2 feet per person). This is also a good standard for most sessions, although you may want to request seating of two people per 6 foot or 3 per eight foot if you’re using large binders or conducting computer training.

The following formula uses the above standards, ensuring comfort and allowing for a greater percentage of the seating area to be utilized.

Step 1: Determine the number of rows that can be accommodated.
a. Take the clear room length and subtract the space between the screen and the front row (two times the screen height) and the space between the back wall and the back row (minimum of four feet).
b. Divide by the distance allotted per row, measured from table front to table front (4.5 feet or 54 inches, assuming the tables are 18 inches wide).
c. Round the resulting figure down to the nearest row.

E.g. 50 (length of room) – 14 (2 x screen height) – 4 (distance from back wall) = 32 (usable room length).
32 ÷ 4.5 (distance per row) = 7.1 rows, rounded down to 7 rows.

Step 2: Determine the number of chairs that can be set in each row.
d. Take the clear room width and subtract space for aisles (normally about 15%).
e. Divide by the distance allotted per chair, measured from chair centre to chair centre (2 feet or 24 inches is the min space per chair for classroom seating).
f. Round the resulting figure down to the nearest chair.
g. Factor in the length of the tables provided by the venue: 6-foot, 8-foot or both.

E.g. 40 (width of room) – 6 (15% of 40 to determine space lost to aisles) = 34 (usable room width).
34 ÷ 2 (distance allotted per chair) = 17 chairs.

If the venue only has 8 foot tables, you need to determine how many eight foot tables can fit in the 34 feet available for seating (34 ÷ 8 = 4.25). The number of chairs in each row would be reduced to 16 (4 tables x 4 attendees per table).

Step 3: Multiply the number of rows by the number of chairs in each row.
E.g. 7 (rows) x 16 (chairs) = 112 people that can be comfortably accommodated in the room.

Banquet Style

Banquet-Style Formula

Most venues use round tables that are 60”, or 72” in diameter. The standard used by the majority of facilities is to allow 5 feet between each round, which provides sufficient room for chairs to be placed around the table and for banquet staff to provide meal service. The ideal number of seats per table is 8 at a 60” round, 9 at a 66” round and 10 at a 72” round.

To determine how many rounds can fit in a given room, it’s helpful to think of each round as a square. Add 5 feet to the diameter of the table (60 inches plus 5 feet = 10 feet) and then calculate how many 10 foot squares can be accommodated in the space using the following formula.

Step 1: determine the number of tables that can be accommodated.
h. Take the clear room length and divide by each table’s linear feet (from the chart below). Round the resulting figure down to the nearest table.
i. Take the clear room width and divide by each table’s linear feet. Round the resulting figure down to the nearest table.
j. Multiply the two numbers.

E.g. 75 (length of room) ÷ 10.5 (linear feet for a 66 inch round) = 7.1 rounded down to 7.
50 (width of room) ÷ 10.5 (linear feet for a 66 inch round) = 4.76, rounded down to 4.
7 x 4 = 28 tables.

Step 2: Subtract excess tables that need to be removed for staging, buffets, rear-screen projection, or chairs directly in front of an exit, etc.

Step 3: Multiply the number of tables by the number of chairs to be set at each table (from the chart below).
E.g. 28 (number of tables) x 9 (number of people at each table) = 252 people that can be comfortably accommodated in the room.
After you’ve taken the time to figure out the capacities of the function rooms, don’t leave the actual setup of the rooms to chance. Be sure to specify, in writing, the standards that you require the venue to follow such as 4.5 feet between table fronts for a classroom setup or 22 inches from chair centre to chair centre for a theatre style setup. You may even have to show the setup crew how to properly place the tables and chairs. (Also be sure to clearly communicate what wall you want the chairs to face). It’s a little extra work but it will ensure that your delegates are comfortable. Remember, comfortable delegates are usually attentive delegates.

How Many People Can Fit at a Banquet Round?

Available Sizes    Linear Feet    Needed Number of People
60” round             10’               6-9 people
72” round             11’               9-11 people

Exhibit Space

Exhibit Space

Exhibit booths: Number of booths x booth length x booth width x 2.
This is a very common and widely accepted formula in the meetings industry. Basically, you determine the area needed for the exhibits and double it to accommodate the aisles, lost space in corners, and other misc space-takers. If you need extra space for registration or food service, just add the gross square footage of those items to the total area required for exhibits.

E.g. 100 booths x 10 (length) x 10 (width) x 2 (aisle space) = 20,000 sq ft of space required to accommodate the booths.

Note: The formula works in reverse. To determine how many 8’ x 10’ booths will fit in a 12,000-square-foot space, divide 12,000 by 2, then 8, then 10 (or simply divide once by 160). You’ll be able to fit 75 booths in the room.

Table Top Exhibits: Think of tabletop exhibits as 6’ x 8’ booths…and follow the above formula for exhibit booths.
E.g. 30 (booths) x 8 (length) x 6 (width) x 2 (aisle space) = 2800 sq ft of space.

Poster Boards: Think of poster boards as 3’ x 8’ booths. And follow the above formula for exhibit booths.
E.g. 200 (posters) x 8 (length) x 3 (width) x 2 (aisle space) = 9,600 sq ft of space required.

Reception

Receptions

Number of people x 10 square feet per person.

Many ballrooms don’t have sufficient foyer or assembly space to comfortably accommodate a reception for several thousand people. This formula will enable you to quickly determine whether a particular area can hold your entire group. If you need extra space for extensive buffets, bars, staging, or props, simply add the gross square footage of those items to the total area required for the function.
E.g. 2000 (no of people) x 10 (sq ft per person) = 20000 sq ft minimum needed.

Note: To visualise what 10 sq ft is, picture yourself standing in a 3 ft square and you’re just about there.

Additional Formulas

Additional Formulas

Dance Floor

Number of people x 2 square feet per person (assuming about 1/3 of the group is dancing at any one time)
Generally, hotel setup crews dislike putting down and picking up a dance floor. It’s heavy and time-consuming. So if you leave the size of your dance floor up to the setup crew, you may end up with a dance floor that’s too small. Use this formula to figure out you requirements.
E.g. 200 (no of people) x 2 (sq ft per person) = 400 sq ft min needed for the dance floor.

Rear Screen Projection

Number of people    Space to add
Less than 100           Add 1,000 sq ft
100-200                   Add 2000 sq ft
200 or more             Add 3000 sq ft

These formulas will help you decide whether there’s sufficient space for rear-screen projection in a function room. To apply them, first calculate the min square footage requirements for theatre style, classroom style or banquet style seating using the formulas given earlier. Then add the appropriate additional square footage from the chart above based on the number of attendees.
E.g. 3,750 sq feet (banquet style seating) + 3,000 square ft (based on 280 attendees) = 6,750 sq ft min to accommodate rear-screen projection.

Note: If your audio-visual needs are elaborate, these formulas may not work.

Stage Height

Room length ÷ 50

Common stage heights are 8", 16", 24" and 32". Our Staging comes in two primary sizes – 4’x8’ and 4’x4’. Be sure to find out what sizes are available and then specify your staging requirements by length, width and height.

E.g.  75 (room length) ÷ 50 = 1.5 ft or 18 inches needed for stage height.