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Capacity calculator
Capacity is the whole legal test under Martyn's Law, and it is the thing most venues get wrong. It is not your fire certificate number and it is not an average Tuesday. It is how many people may reasonably be expected to be present at the same time, staff included.
Step one
Your spaces
Add every area that could be in use at the same time. If you already know a room's figure from your fire risk assessment, use it. If not, enter the floor area and we'll estimate.
Step two
Your people
Staff and volunteers count towards capacity. So do contractors, performers, bar staff, caterers and anyone else on site.
Step three
Your busiest day
Capacity is judged on peak use, not typical use. A single wedding, fair or fundraiser can pull a venue into scope on its own.
What people forget to count
Every one of these has pushed a venue over a threshold it thought it was under.
- Staff and volunteersThe test counts everyone present, not just the public. Fourteen volunteers on a fete day is fourteen people.
- Rooms in use at the same timeA main hall at 180 and a committee room at 30 is 210, not 180.
- Contractors and suppliersCaterers, bar staff, a band and their crew, the bouncy castle operator.
- Outdoor areas you controlA marquee, a car park used for an event, a churchyard during a fair.
- The once-a-year dayThe village show, the Christmas fair, the wedding you take because it pays for the roof.
- Overlaps at changeoverOne group leaving while the next sets up is the busiest ten minutes of the week.
Where the estimates come from
If you enter a floor area, we apply the floor space factors used routinely in fire safety occupancy assessment. They are a reasonable starting point, not a legal answer.
| Type of space | Per person |
|---|---|
| Standing area, bar, dance floor | 0.3 m² |
| Hall with no fixed seating | 0.5 m² |
| Seated dining, café, function room | 1.0 m² |
| Meeting or committee room | 1.0 m² |
| Exhibition or display space | 1.5 m² |
| Shop or retail floor | 2.0 m² |
| Office | 6.0 m² |
Use net usable floor area, so exclude the stage, the bar servery, the kitchen, storage and corridors. If your fire risk assessment gives a figure for a room, that figure is better than our estimate and you should use it.
This is a planning aid, not legal advice, and it does not determine your obligations. The Home Office section 27 statutory guidance is the authority on how capacity should be assessed, and it includes supplementary material on methods. The Security Industry Authority is the regulator. The Venue Record is independent and is not connected to, endorsed by or approved by any government body.