6x12 Cargo Trailer Conversion Summary

The trailer base is a 2017 Mirage 6x12 cargo trailer. I have been working on this conversion since October of 2022, doing absolutely everything myself, and have put in well over 550 hours of work into it.

The full build details, including step by step photos can be found on this page.

Specifications:

• Body size: 6x12 feet
• Axle weight: 2771lb
• Tongue weight: 394lb
• Bed size: 79.5" long, 64.5" wide
• Fresh water tank capacity: 170L
• Grey water tank capacity: 70L
• Refrigerator: 30QT capacity, 12v, very quiet
• Battery capacity: 200ah lithium (LifePo4)
• Interior standing height: 6' 3"
• Ground clearance: 14"
• Stabilizers: 4x 7500lb
• Tongue jack: 5000lb
• Heating: 2KW diesel heater w/ internal controller, thermostat, remote
• Fan: MaxxAir Deluxe, 10 speed, reversible, can be used in the rain
• Water pump: 2.3 GPM
• Water heating: instant, on-demand
• Toilet: 4 gallon, Thetford 92306
• Sink: 15x17x8"
• Insulation: R13 - R25 in walls, ~R15 in ceiling
• Propane: 2x 20lb tanks
• Flooring: 3/4" plywood (original), 1/2" plywood (additional), 10mm waterproof vinyl plank (additional)

This trailer was built for year-round, off-grid camping in absolute comfort. It is built to a level of quality that regular travel trailers simply cannot dream of; even big names like Airstream (while luxurious) are not even remotely comparable. You won't mind MDF and staples here.

We wanted:

• North-south bed; no climbing over each other!
• Residental size bed; no tiny 54x74" "queens" that cannot fit two adults!
• Fully interior water and plumbing.
• Endless electrical power.
• Proper insulation.
• Effective heating and cooling.
• A compact size.

This build achieves all of the above and more.

Exterior

The 6x12 size tucks in nicely behind an SUV, and is narrow enough to be able to see behind the trailer without using additional towing mirrors. A 5000lb tongue jack is installed in the front, and four 7500lb (each) stabilizers are found in the corners. The tongue features two 20lb propane tanks with an automatic changeover regulator. Also on the front is an Anderson connector for charging the electrical system.

The windows, marine access hatches, and the awning are mounted into solid steel tubing which was welded in where/as necessary. Everything is secured with nylock nuts, threadlock, etc.

Roof

The roof is covered in several coats of Herculiner truck-bed liner; it is an entirely waterproof, highly-durable, hard-rubber-like finish. A 10-speed, MaxxAir Fan is installed towards the front, above the kitchen area.

Driver-side

A 30x24", sliding, screened & tinted window is in the front, with a drip-cap above it. To the right of it are four airline tracks which can be used to mount anything and everything. A 23Zero shower stall is mounted here, which provides a 40x40" shower enclosure in just a few seconds.

The black, marine access hatch houses a hot & cold water faucet, shower hose quick-disconnect, as well as fresh water fill inlet.

Passenger-side

A 30x24", sliding, screened & tinted window is in the rear. Above the window is a 10ft wide by 8ft deep awning (with endless adjustment options), with a dimmable LED strip tucked in underneath.

The black, marine access hatch provides a hot & cold water faucet, with a shower hose quick-disconnect.

Below the hatch is a 7x2ft, drop-down table made from 1/4" aluminium. The table flips up and locks in place for transit.

The entry door has the original bar-lock, as well as an RV lock with dual deadbolts.

Rear

Three 4ft long airline tracks are installed for mounting of accessories. A custom-welded, steel rack is mounted to the bottom of these tracks.

On the left of the rack is an unused spare tire, with a Trasharoo tire bag overtop. The bag is very useful for bringing firewood on the way into camp, and hauling out garbage on the way back.

On the right is a waterproof hard-case that contains the 2KW, diesel heater and 5L diesel tank. That 5L of diesel is enough for 4-5 nights of heating. The heating is plumbed into the interior and comes out in a vent at the foot of the bed/kitchen area.

Using the trailer overnight in 3-4C temperatures, the heater ran on the lowest setting (1 of 6) and kept the interior between 24C and 26C with a completely open passenger-side window! The insulation here is no joke.

The exhaust does have a muffler (not pictured) and stores inside the case when not in use. The diesel tank fits 5L, which is enough for 4-5 nights of use, while all wiring runs through waterproof fittings.

Interior

The rear wall and ceiling are heavily SOUND proofed. Butyl-based sound deadening on the rear wall and entire ceiling, plus MLV (mass loaded vinyl) on the rear wall. There is zero noise from raindrops hitting the roof, and the heater is virtually silent (only the diesel pump's ticking can be heard).

Rear wall is insulted with ridgid R5 insulation, then with another layer of R12 fibreglass insulation. In some spots the fibreglass insulation is doubled up.

Side walls are similarly insulated in R12 fibreglass insulation, as is the front wall (with doubling up where possible).

Ceiling is insulated with R10 worth of ridgid insulation, and another R3.7-R7.4 of bubble-foil insulation.

All walls and ceiling are covered in 5/8"-thick, pine tongue & groove paneling, which adds another R1 worth of insulation anywhere it's installed.

The ceiling has 12 round, soft-coloured LED lights. The rear 10 are on one dimmer/circuit, the front 2 are on a separate dimmer/circuit.

The kitchen area features a propane-powered, on-demand water heater, a deep, 15x17" sink, flexible faucet, 1.5"-thick bamboo countertop, and 4 drawers on full extension slides. Drawers are made from 3/4" birch plywood all around.

A removable panel (below the right drawer) provides access to the water pump and plumbing, while a second removable panel (below sink) provides access to the batteries and all electrical components.

A propane-leak detector is wired and installed (not pictured), along with a battery-powered CO detector. A combination CO/smoke detector is also present.

Roller blinds are present on both windows.

The sleeping area is nearly residential king-size. It's easy to add a bunk above the bed, either width-wise or length-wise.

Below the bed are two cavities. The left one can be used for two storage drawers (not built), while the right one is meant for large-capacity storage of heavy objects (ex. firewood). Heavy duty, locking, 32"-long, 500lb-capacity drawer slides are already installed. Add the sliding platform itself and your gear will neatly tuck away under the bed.

To the right of the kitchen area is another storage drawer, 30QT, 12v refrigerator and a brand-new, unused, Thetford 92306 Porta Potti 565E is included. We envisoned keeping the porta potty mobile, so that it can be pulled out when needed, while having several shelves for storage directly above it. It's easy to add shelves for storage here, additional counter space, shelving for toiletries and other misc accessories, etc.