It is a question asked on almost every large-scale project, usually early and usually more than once. How many toilets does the site need? It sounds like it should have a tidy answer — a figure to write on a plan and move on from. In practice it is one of the hardest questions to answer with a single number, because no two sites are the same and no two audiences behave in quite the same way.

Attendance provides a starting point, but it does not provide the complete answer. The correct provision depends on who will use the facilities, how long they will remain on site and how demand will rise and fall across the hours, days or weeks of operation. A workforce compound supporting fifty contractors has very different requirements from a festival welcoming five thousand guests. A twelve-hour public event creates a different usage pattern from a two-hour sporting fixture. A parade route behaves differently from an exhibition hall, and a site serving food and drink will see markedly different demand from one that does not.

Local regulations, municipal requirements and applicable event guidance must always be considered, and they set the floor that any plan has to clear. But calculating the minimum number of units is only the beginning of the work, not the end of it. The regulatory figure tells you what you cannot go below. It does not tell you whether the site will actually work.

The real question is behaviour

The harder and more interesting challenge is understanding how people behave and how the event itself shapes that behaviour. People do not distribute themselves evenly across a site. Popular areas create concentrated demand, particularly during scheduled breaks, intervals and the period immediately after an event finishes, when a large proportion of the audience decides to do the same thing at the same time. Facilities in quieter corners may sit largely unused while a block near the main draw develops a queue long enough to become a talking point.

This is precisely why distribution matters as much as total quantity. A site can hold more than enough units on paper and still fail its users if those units are in the wrong places. Facilities have to be positioned where people will naturally need them: easy to find, within a reasonable walking distance, and reachable without forcing anyone to cross a vehicle route, a service road or a restricted operational area to get there. Good welfare provision is as much a question of siting and pedestrian flow as it is of numbers, and it has to be planned alongside the wider overlay rather than dropped in once everything else is fixed.

If you cannot service it, it does not work

There is a second audience for every toilet block that guests never see, and it is the servicing operation. Cleaning teams need regular, repeatable access throughout the event. Water supplies have to be replenished and waste tanks monitored and emptied, often on a tight cycle during peak periods. Service vehicles frequently need to approach facilities without moving through crowds, which means the route in and out has to be considered at the same time as the position itself.

A block that looks perfectly placed from the guest's point of view can be almost impossible to maintain if nobody has thought about how a tanker or a cleaning team will reach it once the site is full. When servicing is designed in from the start — clear access, sensible vehicle routing, waste and water logistics that match the operating pattern — the facilities stay clean, stocked and open. When it is an afterthought, they fail at exactly the moment they are needed most.

The right mix, not just the right total

Different users also need different facilities, and lumping them together rarely serves anyone well. Accessible toilets must be provided in suitable, genuinely usable locations rather than grouped somewhere convenient for the plan but inconvenient for the people who rely on them. Family facilities, workforce toilets, guest provision, VIP facilities and units for contractors working overnight may all form part of a wider welfare strategy, each with its own placement and servicing logic.

The balance of cubicles and urinals should reflect the expected audience and the way it will use the site, rather than a default assumption. And the unit itself is only part of the experience. Handwashing, lighting, clear signage, adequate queuing space and weather protection all contribute to whether a facility actually works when someone reaches it. A toilet block that is technically present but poorly lit, badly signed or exposed to the weather is not really doing its job.

Planning for the peak, and for reality

The average number of users across a full day can be quietly misleading. What matters operationally is not the average — it is what happens when several hundred people decide to use the facilities within the same short window, at the interval or as the site empties. A good plan anticipates those pinch points and provides capacity, distribution and servicing arrangements capable of absorbing them without a queue becoming the story of the day.

Contingency matters just as much. Units can be taken out of service unexpectedly. Attendance can run higher than forecast. One part of the site can become far busier than anyone predicted once the event is live and the crowd finds its own preferences. A strategy built only around the theoretical minimum leaves almost no room for any of this. Building in a margin — spare units, flexible servicing, a plan that can flex when reality does — is what separates a provision that copes from one that comes apart under pressure.

The mark of a good plan

The better plan, then, is not necessarily the one with the greatest number of units. It is the one that provides the right mix of facilities, in the right locations, supported by a cleaning and servicing operation that can actually keep them running throughout the event. Numbers alone never tell the full story; behaviour, distribution, access and contingency are what make the difference on the day.

Most guests will never think about how many toilets were ordered, where they were placed or how they were serviced. They should not have to. They simply expect to find one, clean and open, when they need it. Meeting that expectation quietly, at scale, across an entire site, is the real measure of a welfare plan that works.

At first glance, planning a site compound can look like a game of Container Tetris. Move one cabin to the left. Rotate another. Slot the toilets into the remaining gap and line the storage units neatly along the fence. Everything fits.

The trouble is that everything fitting does not guarantee that anything functions. A tidy drawing and a working compound are two very different things, and the gap between them is where a lot of daily friction is either designed out or quietly built in.

A small operational headquarters

A site compound is far more than a collection of temporary buildings. On a major project it becomes a small operational headquarters, supporting planning, communication, logistics, welfare, maintenance and decision-making — frequently all at the same time. Hundreds of people may interact with it every single day.

Project managers hold meetings there. Contractors come to collect information and permits. Drivers arrive with deliveries. Suppliers need access, visitors need somewhere to report in, and infrastructure teams need space to store equipment and coordinate their work. The real challenge of compound planning is letting all of these activities happen alongside one another without creating unnecessary friction — because when the compound is congested or confusing, that friction is multiplied across everyone who passes through it.

Location: connected, but out of the way

Location is one of the first decisions, and one of the most consequential. A compound positioned too far from the operation creates long journeys and slower response times, quietly taxing every trip to and from it. Position it too close to the centre of activity, though, and it starts contributing to congestion, noise and conflict between vehicles and pedestrians. The aim is to stay genuinely connected to the project without sitting directly in its way — near enough to be useful, far enough not to be a bottleneck.

Layout is where compounds succeed or fail

The arrangement inside the compound matters every bit as much as where it sits. Offices should be positioned around how teams actually communicate and work together, not just where they happen to slot in. Meeting rooms need to be reachable without routing every visitor through restricted workspaces. Storage areas require practical delivery access rather than a theoretical space on the plan. And welfare facilities should be genuinely convenient for the people using them. Throughout, pedestrian routes, parking, loading areas and emergency access all have to stay clear.

There is also a detail that sounds trivial and absolutely is not: the container doors need to open in useful directions. This is normally discovered shortly after somebody has produced a beautifully symmetrical drawing with half the entrances facing a fence. It is a small thing on paper and a daily nuisance in reality — a neat reminder that a compound has to be planned as a place people move through, not a pattern that looks balanced from above.

The infrastructure behind the boxes

A compound is not just the containers, either. It needs power, lighting, water, wastewater management, internet connectivity, furniture, shade and waste facilities to function as a workplace. Air conditioning and ventilation have to reflect real occupancy and working hours rather than a nominal spec, and the utility routes feeding all of this must be protected from vehicles and the wear of daily activity.

Crucially, these systems have to be considered before the compound goes live — not connected wherever space happens to be left over once the cabins are down. A compound planned around its services works from day one. A compound where the services were an afterthought spends its whole life compensating for it.

A facility that evolves with the project

The best compounds also change as the project moves through its phases. During the build, contractor offices, induction areas and storage tend to dominate. As the project shifts into live operations, meeting spaces, communications and operational control become more important. During the dismantle, storage and logistics activity ramps up again, even as the compound itself gradually disappears. A layout with some flexibility built in can adapt to all of this without the whole operation having to be picked up and relocated each time the emphasis changes.

The strongest compounds are rarely defined by their size. They succeed because they make daily working life easier. People know where to go. Information moves efficiently. Deliveries arrive without blocking the entrance. Facilities work as expected, and teams can concentrate on delivering the project rather than fighting the environment around them.

From the outside, a site compound may still look like a collection of rectangular boxes. The pieces may fit together like Tetris.

The real skill is making sure the people do too.

The project approaches opening day. Deadlines are advancing. Contractors are moving across the site. Installations are nearing completion, and the operations team is preparing to receive its first guests. Everything visible is coming together.

But hidden deep within the project folders, an overlooked force is waiting. Drawings. Permits. Inspection records. Meeting minutes.

The paperwork is about to strike back.

Overly dramatic? Perhaps slightly. Nobody has ever walked onto a project site and announced that they cannot wait to read the day's documentation. People get excited about opening days, major installations, big deliveries and visible milestones — the things you can photograph. Documentation sits quietly in the background, attracting very little attention and even less affection.

Until something goes sideways.

Then, quite suddenly, everyone wants to know exactly what was agreed, approved, inspected, tested, changed or communicated. Which drawing was issued? Who approved the change? Was the equipment inspected? What did the method statement require? Was the contractor informed? Where is the record? The questions arrive all at once, and they all have the same shape: show me the paperwork.

The least glamorous, most valuable thing on site

Documentation may be one of the least glamorous parts of project delivery, but it is also one of the most valuable. Drawings, risk assessments, method statements, inspection records, permits, meeting minutes, delivery records and maintenance logs together form the memory of the project — the record of how it was planned, delivered and operated. Take that record away and all you have left is what people happen to remember, which on a large, fast-moving site is never enough.

Its purpose is not simply administrative, and treating it as box-ticking is where projects get into trouble. Good documentation exists so that people can make informed decisions. Contractors can confirm access and installation requirements. Infrastructure teams can verify procedures. Operations teams can understand where their responsibilities begin and end. Health and safety teams can review the controls agreed for the work. Everyone works from the same information rather than from their own version of it.

Why it matters more as a project grows

This shared record becomes more important the larger a project gets. A big site may involve dozens of contractors and hundreds of workers, with plans changing rapidly as the build develops. Information moves fast, and in that environment things drift. Verbal instructions become distorted as they pass from person to person. Assumptions multiply. And yesterday's drawing stays open on someone's laptop long after a revised version has been issued — which is precisely how two teams end up building to two different plans without either of them realising.

Documentation is what holds that together, but only if it is accurate, current and accessible. Those three words are doing a lot of work. A perfectly written document buried in the wrong folder is of almost no use. So is an inspection record nobody can find, or a drawing without a clear revision number that leaves people guessing whether they are looking at the latest version. Effective document control is not about producing more paper; it is about making sure the right people can find the right information at the moment they actually need it.

The time it quietly saves

Good documentation also saves a great deal of time, even though the saving is rarely visible. The correct drawing prevents hours of confusion on site. A clear method statement heads off the same discussion being had three times. An inspection record confirms in seconds that work has already been checked, rather than sending someone back to check it again. Properly recorded meeting decisions stop the same argument returning every few days, because the answer is written down and dated rather than relitigated from memory.

The trouble is that all of this success is invisible. Nobody celebrates the information that was easy to find. Nobody tells the story of the drawing that quietly prevented an installation error, or the maintenance record that helped resolve a fault the night before opening. Documentation only becomes noticeable when it is missing — and at that point it tends to return as the most powerful force in the room, capable of stopping work, opening questions and consuming a day that nobody had spare.

Records that earn their place

The strongest project teams understand this, and it shapes how they work. They do not create documents simply because somebody requested them or because a folder needs filling. They create and maintain reliable records because those records help the project operate safely, consistently and efficiently — because good document control is a delivery tool, not a filing exercise. The paperwork is there to be used, not admired.

So the documentation may spend most of the project sitting quietly in the background, unloved and unread, doing nothing to draw attention to itself.

But when the questions begin, may the correct revision be with you.