How many porta potties does a construction site need?
OSHA 29 CFR 1926.51 sets the minimum: 1 toilet facility for up to 20 workers, then 1 toilet seat and 1 urinal per 40 workers from 20 to 199, and per 50 workers at 200 or more. Most contractors order one unit per 10 workers, because that is what stays usable across a week of standard servicing. Call 1-833-520-0680.
Who is this unit for?
New build and residential construction sites- Commercial and civil engineering projects
- Roadworks and utility crews
- Long duration renovation projects
- Any site without access to a permanent restroom
What are the specifications?
| Spec | Detail |
|---|---|
| Billing | Monthly, with weekly servicing included |
| OSHA minimum, up to 20 workers | 1 unit |
| OSHA, 20 to 199 workers | 1 seat and 1 urinal per 40 |
| Practical ratio | 1 unit per 10 workers |
| Hand washing | Required where work involves contaminants |
| Truck access needed | Within about 25 ft of each unit |
Why do contractors order above the OSHA minimum?
Because the minimum is a legal floor, not a usability target. One unit for 20 workers is compliant, and it will also be unpleasant by Wednesday.
The working ratio is one unit per 10 workers, which matches the practical capacity of a 60 to 70 gallon tank across a five day week on standard weekly servicing. At that ratio the unit is still usable on Friday, which is the actual goal.
How do you count your crew?
Use the peak number on site at one time, not the average and not the total headcount across the project. A site with 60 people during the framing phase and 15 during fit out needs provision sized for 60 while that phase runs.
That is also why provision should be reviewed between phases. Carrying six units through a three month fit out with a crew of 12 is money spent for nothing.
What drives the servicing frequency?
Workers per unit and temperature. Weekly service handles about 10 workers per unit in mild conditions. Push past that, or run through a hot summer, and the tank reaches its practical limit before the truck comes back.
The symptom is predictable: units that are fine for the first two days of the week and avoided by the end of it. If the crew is walking off site to find a restroom, the schedule is wrong rather than the unit count.
Where does hand washing fit in?
OSHA requires hand washing facilities where the work involves contaminants. In practice that covers a wide range of construction activity, and a hand wash station beside the units is the straightforward way to provide it.
Standard units carry a sanitiser dispenser, which is useful but is not the same provision. Where the requirement applies, order the station.
What about access over the life of the project?
This is the most common avoidable cost on a long rental. A unit that was easy to service at ground break ends up behind scaffolding, inside a fenced pour or beyond a stockpile, and the service truck cannot reach it.
A missed visit normally still counts as a visit. Agree a position that survives the build and keep the approach clear on service days.
How does booking work?
Call with the headcount and dates
We connect you with a local provider. Tell them whether workers or guests will be using the units.
Confirm the count and the schedule
The provider sets the unit mix, the servicing frequency and the placement, then quotes the whole rental.
Delivery, servicing and collection
Units arrive clean. The service truck keeps to the agreed schedule, and collection is on the end date.
What does it cost?
| Market type | Typical range |
|---|---|
| Monthly, major metro | $175 to $325 |
| Monthly, mid size city | $155 to $285 |
| Monthly, smaller market | $140 to $260 |
What is inside the unit?
Included
- Molded seat with a self closing lid
- Urinal for faster turnover
- Toilet paper holder restocked at every service
- Hand sanitiser dispenser
- Internal latch with an occupied indicator
- High visibility exterior suited to an active site
Servicing schedule
Weekly the standard: tank pumped, interior washed, paper restocked, deodoriser added.- Twice weekly where a unit serves more than about 10 workers, or in sustained heat.
- On request additional visits during peak phases, billed per visit.
Fittings vary slightly between manufacturers. Your provider confirms what the specific unit includes and how often it will be serviced.
Where should the unit go?
Put units just inside the site entrance. It keeps the service truck off the active work area, gives the crew a short and obvious walk, and means the position still works when the build progresses and the site layout changes.
A standard unit occupies roughly 4 by 4 feet with the door opening outward, so allow about 5 by 5 feet of clear space. The service truck needs to get within about 25 feet of the unit, which is the constraint that decides most placement questions.
Related restroom options
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Guides
Construction Site Porta Potty questions
What does OSHA actually require?
One toilet facility for up to 20 workers. From 20 to 199 workers, 1 toilet seat and 1 urinal per 40 workers. At 200 or more, 1 toilet seat and 1 urinal per 50 workers.
Is the OSHA ratio per shift or per project?
It is based on the number of workers on site at one time. Use your peak crew count, not the total number of people who will work on the project.
Is weekly servicing enough?
For up to about 10 workers per unit, yes. Above that, or in sustained heat, twice weekly is what keeps units usable.
Do I need a hand wash station as well?
Where the work involves contaminants, OSHA requires hand washing facilities. Sanitiser alone is not a substitute in those conditions.
How is a job site rental billed?
Monthly, with the weekly servicing included in the figure. Extra service visits and long carries from the truck to the unit are the usual add ons.
Can units be moved as the site changes?
Yes, providers can reposition units, usually for a fee. It is cheaper to pick a position at the start that will still work in month three.
Who wrote this page
Written and fact checked by the Dumpster Porta Potty USA editorial team. We check container sizes, servicing intervals and price ranges against published provider rate sheets and federal guidance, then update the page when those change.
Last updated . Read our editorial policy.
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