What is a 4 stall restroom trailer?
A 4 stall restroom trailer is a towable unit with four private restrooms behind two exterior doors, each side carrying two flushing toilets, sinks with running water, mirrors, lighting and its own climate control. The common build splits into a two-toilet women's side and a men's side with one toilet and one or two urinals, which is why the men's queue clears faster than the stall count suggests.
This is the size most Philadelphia events actually want. Two stations feels tight the moment a reception passes 100 people, and eight stations is more trailer than a garden or a rowhouse block can physically take. The restroom trailer overview compares all three, with the 2 station unit below it and the 8 station unit above.
4 stall restroom trailer dimensions and specs
Typical manufacturer specification ranges for a four-station towable restroom trailer:
| Spec | Typical figure |
|---|---|
| Body length | 16 to 20 ft |
| Body width | 8 to 8.5 ft |
| Overall length with tow vehicle | 40 to 46 ft |
| Waste tank | 300 to 650 gal |
| Fresh water tank | 100 to 200 gal |
| Dry weight | 4,500 to 7,000 lb |
| Power | Two 120 V, 20 amp circuits |
| Rooms | 4 across 2 entrances |
Two circuits matter more than the number looks. NFPA 70, the National Electrical Code, puts a 20 amp branch circuit at roughly 2,400 watts, and a four-station trailer runs two air conditioning units plus pumps and lights, so a single household outlet will trip. At 8.34 pounds per gallon, a full 650 gallon waste tank adds about 5,400 pounds, which is why the unit gets pumped in place rather than towed out loaded.
What does a 4 stall restroom trailer cost in Philadelphia?
| Rental period | Typical range |
|---|---|
| Per day | $350 to $700 |
| Weekend | $1,100 to $1,900 |
| Per week | $1,300 to $2,400 |
| Per month | $2,600 to $4,200 |
Market ranges reviewed July 2026, not a quote. Delivery in a weekly context typically adds $50 to $150, a one-day timed event drop $100 to $500, and each service visit $30 to $220. A luxury-finish four-station build prices roughly 25 to 60 percent above these figures, covered on luxury restroom trailers. Every line item is broken out on restroom trailer rental cost, and porta potty rental cost has the standard-unit comparison.
How many people does a 4 stall trailer serve?
Portable Sanitation Association International guidance is one restroom per 50 to 100 guests over four hours, plus 15 to 20 percent when alcohol is served. Four stations therefore covers roughly 200 guests dry and about 165 with a bar open, which is the size band most Philadelphia weddings and corporate events sit in.
On a construction site the maths is different. OSHA 1926.51(c)(1) requires one toilet for 20 or fewer workers, and one toilet seat plus one urinal per 40 workers above that, so a four-station trailer covers a crew of roughly 80 on paper. Most Philadelphia sites still pair it with standard units at the far end of the job, because a trade walking 300 feet to a trailer is a trade off the tools. Run your own numbers on how many porta potties do I need and check the site rules on OSHA portable toilet requirements.
Where a 4 station trailer works in Philadelphia, and where it does not
A four-station unit needs about 45 feet of clear straight approach with the tow vehicle attached, plus room to swing. That rules out a good share of the city's rowhouse blocks and rules in everywhere with a lot.
Works well here:
- The paved lots around Lincoln Financial Field, Citizens Bank Park and the Wells Fargo Center, which are the easiest trailer sets in Philadelphia
- Fairmount Park lawns and drives with vehicle access, for tented dinners and daytime festivals
- Penn's Landing and the Delaware waterfront, where enclosed climate control beats an open unit once the wind picks up
- University City and hospital construction sites, where the trailer serves supervisors, inspectors and clinical staff on construction site services
- Larger Chestnut Hill, Bryn Mawr and Lower Merion properties with a drive that loops or a wide gate
Rarely works: a South Philadelphia or Fishtown street parked both sides, a Manayunk block steep enough that leveling eats the whole set, or a Society Hill court on Belgian block. On those jobs a 2 station trailer or a row of deluxe flush units is the honest answer. The placement guide has the approach checklist.
Permits, accessibility and winter operation
Philadelphia routes portable toilet and holding tank applications through the Department of Public Health under its infectious waste program rather than a streets or transportation department, which catches out contractors who have filed in other cities. Private property placements sit outside that process. See porta potty permit requirements.
Accessibility is the other planning item. The 2010 ADA Standards limit ramp slope to 1:12 in section
405.2, so a 36 inch trailer floor needs 36 feet of ramp, and an accessible stall needs the 60 inch turning clearance in section 604.3.1. Most four-station units cannot meet that without a lift, so an ADA ground-level unit usually goes beside the trailer. Full detail on ADA restroom requirements. From December through March the trailer has to run heat overnight or the fresh water lines split, which is the same problem covered on porta potties in winter.
How do you book a 4 stall trailer in Philadelphia?
Service on a four-station unit means pumping the waste tank, refilling the fresh water, restocking paper, soap and towels, and wiping down both sides. ANSI/PSAI Z4.3, the American National Standard for nonsewered waste-disposal systems, sets weekly service as the baseline on a standing unit, and events above 300 guests usually get a mid-event visit booked in advance.
Have five things ready: the address with cross streets, the dates and hours, the headcount, whether two 20 amp circuits and a hose bib are within about 100 feet, and whether the pad is private property or public curb. The rental checklist covers the rest. Send it through the quote form or the contact page. Event planning sits on wedding restroom rental and event restroom rental, showers on the shower trailer page, and same-day work on emergency porta potty rental. We deliver across the city and out to King of Prussia, Lower Merion and the rest of the areas we serve around Philadelphia.
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