Meeting Room Size Calculator: Room Dimensions from the Table

What it calculates

The calculator works out the inside dimensions of a meeting room or boardroom from the number of people who need to sit at the table. It gives:

• the table size, from the seats on each long side and any seats at the ends;
• the room length and room width, inside wall to inside wall;
• the floor area in square metres and square feet;
• the area for each seat, a quick way to compare rooms of different sizes.

A breakdown shows how much of each dimension is table, clearance and display zone, so it is easy to see which allowance is driving the size.

Inputs

Seats at the table is the number of people who sit at the table itself. Chairs along the wall for extra attendees are not counted.

Seats at the table ends can be none, one end or both ends. With a screen at one end, the usual choice is none or one.

Table width is the depth of the table across, in millimetres. Narrower tables save room width; wider ones give space for laptops and papers and keep people facing each other at a comfortable distance.

The assumptions panel holds the width per seat along the table, the clearance from the table edge to the wall behind the chairs, and the extra depth at the display wall.

Method

The room is built up from the table:

1. Seats per long side = (seats − end seats) ÷ 2, rounded up.
2. Table length = seats per side × width per seat + 300 mm for each end seat.
3. Room length = table length + 2 × clearance + display depth.
4. Room width = table width + 2 × clearance.
5. Area = room length × room width.

The 300 mm for each end seat lengthens the table slightly so a chair at the end does not collide with the chairs at the corners. When the number of side seats is odd, one side has a seat fewer, and the table length is set by the fuller side.

The same clearance is used at both ends of the table as along the sides. At the display end, the display depth is added on top, so the people nearest the screen are not sitting against it.

Assumptions

These are common space-planning allowances, not rules. They suit a typical meeting room with task chairs. Larger executive chairs usually need a wider seat allowance and more clearance; a stand-up or huddle room can be planned tighter.

Limitations

• Rectangular room, one table. Boat-shaped, U-shaped, hollow-square and classroom layouts follow different geometry.
• Inside dimensions only. Wall thickness, columns, glazing mullions and door swings are not included. A door that opens into the room needs its own clear zone.
• No back-row seating. Chairs along the walls for extra attendees need more width.
• No acoustic, lighting or AV design. A room that is the right size can still be noisy, echoing or poorly lit for video calls. Those are designed separately.
• Accessibility is not checked. If a wheelchair user needs to reach a place at the table and move around the room, the designer checks the turning space and routes on the plan.

Worked example

A ten-seat meeting room with no seats at the ends and a screen at one end, using the default allowances:

So a ten-seat room with a 3,000 × 1,200 mm table needs a room of about 6.0 × 3.6 m. Adding a seat at each end for twelve people (twelve seats, two at the ends) lengthens the table to 3,600 mm and the room to 6.6 m, giving 23.8 m² (256 sq ft).

The office space planner's default boardroom allowance of 300 sq ft is larger than this result. The difference is room for a side credenza, a few chairs along a wall or a wider table, which a boardroom often has.

How engineers use it

An interior designer uses this calculation at the space-planning stage to decide how big each meeting room needs to be before placing it on the floor plan. Rooms are then usually fitted to the building grid: a room that needs 6.0 m in a building with a 1.5 m window module might be drawn at exactly four modules, so partitions meet mullions cleanly.

Once rooms are placed, the size feeds the next round of design. The AV consultant checks the viewing distance to the screen and the camera coverage. The acoustic design sets the wall build-up, door and ceiling to suit the privacy the room needs. The lighting designer sets the light levels and controls, and the HVAC engineer sizes air and cooling for the number of people.

When a professional design must replace it

Use the calculator to brief a designer, to compare rooms on a test fit, or to check whether a room on an existing floor will take the table you have in mind. Replace it with a designer's furniture layout before ordering a table or building the walls. The layout confirms the door position, the access route around the table, the screen and camera positions, and how the room sits on the building grid.