Once you've decided a trailer is the right platform for your business (if you haven't, start with our skid vs. trailer vs. van guide), the next question is size. We build three main sizes here in Oregon City: the 5x8 Portlandian, the 6x10 dual axle Eagle Series, and a 7x14 super duty build. Each one fits a different kind of business, and buying the wrong size is an expensive mistake to undo.
We ran our own pressure washing company for more than ten years before we started building equipment, so this is the same thinking we'd use if we were buying again.
The short answer
- 5x8 if you're starting out, washing mostly residential, and need something small and easy to tow and park.
- 6x10 dual axle if you're building a full-time business and want everything (ladders, surface cleaner, soft wash, room to add services) on one trailer that still fits in a home garage.
- 7x14 if you already have the commercial work, the crew, and the tow vehicle, and you need hot water, big water capacity, and several systems on one rig.
Side by side
| Size | Axles | Liquid on the builds in our videos | Best fit |
|---|---|---|---|
| 5x8 Portlandian | Single | 100 gal water, 100 gal chemical | Starting out, residential, tight neighborhoods |
| 6x10 Eagle Series | Dual | 200 gal water buffer, 100 gal bleach, 7 gal soap | Full-time residential and light commercial, garage storage |
| 7x14 Super Duty | Dual, upgraded axles and hitch | 525 gal water, 100 gal bleach, plus neutralizer and surfactant | Commercial crews, hot water, multiple soft wash systems |
Every build is custom, so tank sizes and equipment change to fit the job. The numbers above are what was on the actual trailers in our videos.
5x8: The Portlandian
The Portlandian is our compact trailer, and we've been building it for three to four years. It's still a full professional setup, not a stripped-down starter kit. Standard, it comes with:
- A Honda 5.5 GPM pressure washer, upgradable to a Honda 8 GPM
- Two 100 gallon tanks (water and chemical) plus a 7 gallon soap tank
- A Flojet 12V soft wash pump feeding our Pro Mixer XL, with a bleach rinse valve
- Three Expert full-frame aluminum hose reels with 316 stainless manifolds
- Quarter-inch aluminum tank straps, and a reel rack welded into the trailer frame instead of bolted on afterward
The one in the video below is upgraded to the 8 GPM Honda gear drive we spent almost a year developing with BE, with a block-mounted Pulsar unloader, and it adds a FlowPro downstream system.
Who it fits: a solo operator or small crew doing mostly residential house washing and flatwork, who wants something easy to tow, back into a driveway, and park at home.
The trade-off: water capacity and deck space. With a 100 gallon buffer, you're relying on the customer's spigot to keep up, and there's limited room to add a second system later. A mini isn't the platform for hauling large amounts of water.
6x10 dual axle: The Eagle Series
A dual axle on a 6x10 is unusual, and we did it on purpose. Most washers who are starting out or growing store their trailer in a residential garage, and once you go bigger with the hitch, it often won't fit. The 6x10 keeps the footprint garage-friendly, and the second axle carries the water weight safely.
On the Eagle Series 6x10 setup:
- Reel rack welded into the frame, using the same 2-inch tube as the trailer itself, not thinner add-on material
- Optional ladder rack, welded in and painted with the trailer, with a ladder stop
- Locking aluminum surface cleaner rack with stainless hinges that tucks under the ladder rack and opens on the curb side, so you're not stepping into traffic to unload it
- 8 GPM Honda GX690 gear drive with a block-mounted Pulsar unloader and an upgraded charging system (26 amps versus about 19 stock) that keeps the soft wash battery topped up
- Two 100 gallon tanks tied together into a 200 gallon buffer, which also baffles the water so it doesn't slosh and push the truck around on the road, plus a 100 gallon bleach tank and a 7 gallon soap tank
- Soft wash and downstream: a Pro Mixer XL with a rinse valve feeding a FlowJet 12V pump, plus a remote-controlled FlowPro Gen 5 downstream system
There's also room for add-ons. One recent 6x10 left our shop with a pure water cart for window cleaning, plumbed off one of the reels.
Who it fits: a full-time washing business, especially one running a vehicle that can't be dedicated to the business. Ladders, surface cleaner, hoses and every system stay on the trailer, so you hook up and go.
The trade-off: it's more trailer to tow and costs more than a 5x8, and it's still not built for the water volumes of a heavy commercial rig.
7x14: built for commercial crews
The 7x14 is a different class of rig. The one in the video above shipped to New York and carried:
- Upgraded axles and an upgraded hitch, because it carries a lot of weight
- A 525 gallon water tank, a 100 gallon bleach tank, a 7 gallon neutralizer tank, and a 16 gallon surfactant tank
- A hot water system, with a 22 gallon diesel tank
- Three soft wash systems (12V, LoFlow and MoFlow) plus a remote-controlled FlowPro Gen 5, and a four-port mixer that pulls from the neutralizer tank
- An 8 GPM, 3,500 PSI gear drive with a block-mounted Pulsar unloader
- Six electric hose reels with rolling reel guides, and a ported quick-connect panel so any hose can connect to any system
- A second water inlet into the buffer, a 1.5 inch drain, and a locking surface cleaner rack underneath
Who it fits: an established business running commercial flatwork, hot water work, and roof or house washing out of one rig, usually with a crew.
The trade-off: you need a tow vehicle rated for the load, somewhere to park it that isn't a typical home garage, and a bigger budget. See the 7x14 super duty build for the full spec.
One note: hot water doesn't automatically mean a 7x14. The Hot Eagle puts hot water on our dual axle platform. If you're weighing that decision, read hot water vs. cold water first.
Water weight decides more than you think
Water weighs about 8.3 pounds per gallon. That adds up fast:
- 200 gallons of liquid on a 5x8 is roughly 1,700 pounds
- 300 gallons on a 6x10 is roughly 2,500 pounds
- The 7x14 above carries well over 5,000 pounds of liquid alone, before the machines, reels, hose, and the trailer itself
Size the trailer to the weight it will carry when it's full, and check your tow vehicle's rating before you pick a size, not after. This is also where the axles, tires and frame matter most, and where cheap builds most often cut corners.
What shouldn't change with size
A smaller trailer should be smaller, not cheaper-built. Whatever size you buy, from us or anyone else, check how it's put together: whether the reel rack and ladder rack are part of the frame, how the tanks are strapped, the hardware, the wiring, the plumbing, and the hose reels. We put the full checklist in our pressure washing trailer cost guide, along with real prices for each size. You can also see how we build on our Why EPW builds are different page.
Four questions that usually settle it
- Where will it park at night? If the answer is a home garage, that rules out the 7x14 and points you to the 5x8 or 6x10.
- What's going to tow it? Your tow vehicle's rating sets the ceiling on how much water you can carry.
- How much water do your jobs need? Residential work on city water is easy on capacity. Commercial flatwork, rural jobs, and fleet work need a bigger buffer.
- What will you be selling in two years? If soft wash, hot water, or window cleaning is in the plan, buy a platform with room for it.
Our honest take
For most washers building a full-time business, the 6x10 dual axle is the sweet spot: it carries everything you need, has room to grow, and still fits in the garage. The Portlandian makes sense when small size and easy towing matter most. The 7x14 makes sense when the commercial work and the crew are already there.
Every build comes with training, and we offer financing. If you're not sure which size fits, that's what a discovery call is for. Tell us about your tow vehicle, where you'll park, and the work you're bidding, and we'll tell you straight what we'd build.
Book a Discovery Call or call the shop at 503-403-6185. Browse all of our pressure washing trailers.
