Reference
The rules, and where the numbers come from
Every warning the planner shows is one of the checks below. They are common venue guidance and your own settings, not a code review, and no layout here is an approval. Your venue and your local fire code decide.
Table spacing
Measured edge to edge between table tops, never centre to centre. Two 60 inch rounds whose centres sit 114 inches apart leave a 54 inch gap, and it is the gap that has to hold two chairs and a path.
| Gap | What it allows |
|---|---|
| 54 in | Two chairs back to back, and a server can pass. Two people cannot pass each other. |
| 60 in | Two chairs back to back and two people passing. Usual ask for plated service. |
| 72 in | Comfortable, and enough for a service trolley. |
The 54 figure comes from roughly 18 inches of chair depth each side plus an 18 inch path. Change the chair and the number changes with it.
Rows can run straight or staggered. Staggered rows interleave, so they sit closer front to back at the same edge gap, but the half-pitch shift can cost a whole column on a narrow floor. The planner lays out both ways and keeps the better one rather than preferring a pattern.
Seats per table
Round tops take one seat per 6 inches of diameter at a tight setting, and two fewer for comfort. This reproduces the rental catalogues exactly, which a circumference calculation does not at 66 and 72 inches.
| Diameter | Comfortable | Tight |
|---|---|---|
| 48 in | 6 | 8 |
| 60 in | 8 | 10 |
| 66 in | 9 | 11 |
| 72 in | 10 | 12 |
Rectangular tops count the long sides at about 23 inches per seat, plus one per end where the table is at least a chair wide. An 8 ft by 30 in banquet takes 10.
Aisles and egress
A marked path holds its width along its whole run, and anything intruding on it flags. Paths marked as egress use the higher minimum and always draw, since the constraint matters most when nobody is looking for it.
| Path | Default minimum |
|---|---|
| Service aisle | 36 in |
| Egress route | 44 in |
| Accessible route | Set your own. 48 in is a common ask. |
These are defaults you can change, not code. Occupancy and egress width are set by your local authority and the venue, and they are the ones who decide.
Sight lines
A table fails the sight-line check when a straight line from its centre to the focal point crosses a fixture. Fixtures block: pillars, poles, risers. Tables and zones do not, since a person sees over a table but not through a pillar.
Set the focal point to the stage or the head table. Seats flagged here are the ones worth reseating a VIP out of.
Getting things in
A rigid object rounding a right-angled corner between two runs of width a and b is limited by the ladder-around-a-corner result:
L = (a^(2/3) + b^(2/3))^(3/2)
The object’s own thickness comes off both runs first, because the far face has to stay inside the corridor through the whole sweep. A plain diagonal under-reports this badly and will tell you something does not fit when it does.
Through a doorway, the two smallest dimensions must clear the opening’s width and height. Through a lift, the longest dimension goes against the cab diagonal, since a long piece rides corner to corner.
Units
Every length is stored as a whole number of millimetres, whatever you type. That matches the CAD convention, avoids drift under repeated moves, and converts cleanly to inches. Exports carry millimetres and declare it.