Enclosed Trailer Camper Conversion

What Is an Enclosed Trailer Camper Conversion?

An enclosed trailer is a simple, weatherproof box — originally designed to haul cargo. A camper conversion takes that empty box and transforms it into a fully livable space with insulation, electrical, plumbing, heating, and finished interiors. The result is a camper that costs less than an RV, more space than a van, and can be towed by almost any full-size truck or SUV.

The terms "enclosed trailer" and "cargo trailer" are used interchangeably. Both refer to the same type of equipment. What matters is whether it's empty and ready for conversion, or already partially built out.

Why Choose an Enclosed Trailer Over a Van or RV?

People pick enclosed trailers for three main reasons: cost, space, and flexibility.

More Space Per Dollar Than a Van

A 6x12 enclosed trailer gives you 72 square feet of interior space. A 7x16 gives you 112 square feet. For comparison, a Sprinter van is about 100 square feet. The upfront cost is significantly lower, and you don't lose the layout efficiency that comes with a vehicle-shaped shell. You're working with a rectangle, which is actually easier to optimize for living space.

Use Your Existing Vehicle

You don't need to buy a vehicle and convert it simultaneously. If you already have a truck or SUV, you can convert an enclosed trailer and tow it when you want to camp. This spreads costs over time and lets you get the tow vehicle sorted before you commit to the trailer build.

Flexibility

Detach the trailer at camp and still have your vehicle free to run errands, explore, or get supplies. Unlike a van, your daily driver isn't locked into RV mode. You get the comfort of a full camper when you're camping and the freedom of a regular vehicle when you're not.

Simpler to Build and Maintain

Trailers don't need engine work, transmission repairs, or vehicle-specific systems. You're just building out the interior with electrical, plumbing, insulation, and cabinetry. That means fewer moving parts, fewer things to go wrong, and simpler maintenance.

What Size Enclosed Trailer Should You Convert?

Enclosed trailers come in a wide range of sizes. Here are the ones that work best for camper conversions:

6x12 Enclosed Trailer

Interior space: 72 square feet. This is the entry-level conversion size. A 6x12 works perfectly for weekend camping, couples, or anyone building on a budget. It fits a bed, a compact kitchen, some storage, and basic systems. Most vehicles can tow it comfortably.

A typical 6x12 setup includes a queen bed in the back, a two-burner stove and small sink along one wall, storage underneath the bed, and simple lighting and power. Bathroom facilities are usually external (outdoor shower, campground facilities) rather than built-in, since interior space is tight.

7x12 Enclosed Trailer

Interior space: 84 square feet. One extra foot of width makes a significant difference. You can fit a larger kitchen, better storage, and slightly more comfortable living space. Still tows easily with most SUVs and trucks.

7x14 Enclosed Trailer

Interior space: 98 square feet. This is the sweet spot for full-time living or extended trips. You get room for a proper kitchen with counter space, a real bathroom with shower and toilet, a comfortable bed, and dedicated living area. It's the most popular size for people who want to live in their conversion for months at a time.

7x16 Enclosed Trailer

Interior space: 112 square feet. This is as big as you'll reasonably go with a trailer. It offers more space than most van conversions, room for a full kitchen, a spacious bathroom, multiple sleeping options, and dedicated workspace. Requires a full-size truck to tow safely.

8.5x20 Enclosed Trailer

Interior space: 170 square feet. Some people go larger. An 8.5x20 is massive — you're getting close to a small studio apartment. Most require a heavy truck or commercial towing setup. We can work with these, but they're less common.

What Systems Go Into an Enclosed Trailer Conversion?

Insulation

We use Thinsulate insulation in the walls and XPS foam board on the floor. Thinsulate maintains R-value even when compressed, and XPS foam is durable and doesn't absorb water. We don't use vapor barriers — they trap moisture in a moving vehicle and create mold problems.

The ceiling gets insulated too. Some conversions go with a minimal finish on the ceiling (basic paint or fabric), while others get full headliner treatment. The more insulation, the better the climate control performance.

Electrical System

A typical enclosed trailer conversion includes:

• Battery bank: 100-400Ah lithium, depending on size and usage. Larger trailers and full-time users lean toward 300-400Ah.
• Inverter: 3000-4000W to handle AC appliances and simultaneously powering multiple devices.
• Solar: 400-800W of panels on the roof. Smaller setups might skip solar entirely, while larger rigs go to 1000W+.
• Distribution panel: Standard RV-style breaker panel, just like you'd find in any RV. Everything goes through proper circuit breakers.
• Outlets and lighting: 12V LED lighting throughout, with standard 110V outlets via the inverter for laptops, chargers, and small appliances.

Plumbing System

Plumbing is simplified compared to home systems, but it covers the essentials:

• Fresh water: 40-100 gallon tank depending on trailer size and your usage patterns.
• Gray water: Tank for sinks and shower drainage. 30-50 gallons is typical.
• Black water: Only if you're including a flush toilet. Cassette toilets and composting toilets avoid the need for black water tanks.
• Water heater: Tankless propane or small tank heater for hot water. Some builds skip this and use cold water only.
• Tubing: PEX throughout. It doesn't corrode, handles freezing better than copper, and is easier to install.

Climate Control

Heating: Propane heater (most common) or diesel heater for more even heat and quieter operation. Small electric heaters are an option if you're boondocking near shore power.

Ventilation: Roof vents, windows, and ceiling fans. We prioritize passive ventilation because AC is power-hungry and space-limited in trailers.

AC: Not common in trailer conversions, but possible with larger battery banks and solar. Most people rely on ventilation, shade, and timing (camping in cooler seasons).

Interior Layout and Finishes

The interior includes all the cabinetry, shelving, flooring, walls, and furniture that make it feel like a home rather than a metal box.

• Walls: Marine plywood, aluminum composite, or laminate — something that's durable and light.
• Flooring: Vinyl, bamboo, or sealed plywood. Easy to clean and tough enough for daily use.
• Cabinetry: Custom-built for your layout. Kitchens, bathrooms, sleeping platforms, and storage are all built to fit the space efficiently.
• Appliances: Small stove, compact fridge (12V RV fridge or smaller), and potentially a microwave or oven depending on power budget.
• Bed: Custom frame and mattress that fits your layout. Usually positioned to maximize headroom and floor space.

How Much Does an Enclosed Trailer Conversion Cost?

We use the same pricing structure for enclosed trailer conversions that we use for vans, because the build complexity is similar:

These costs cover the conversion work only. Add $5K-$15K for the used trailer itself, depending on size and condition. That's your true total project cost.

The beauty of building a trailer is that you can spread costs. Get the conversion done when you're ready to start camping, not all at once. You can also do certain upgrades (like adding solar or expanding the kitchen) after the fact.

Should You Convert an Enclosed Trailer or a Van?

Both work as campers. Which one is right for you depends on how you plan to use it.

When an Enclosed Trailer Makes Sense

• You want maximum space: A 7x16 trailer gives you more floor space than any van.
• You already have a tow vehicle: No need to buy and convert a van simultaneously.
• You want to separate camping from daily life: Detach the trailer and keep your vehicle free.
• You're building on a budget: Trailers cost less per square foot than vans.
• You prefer simplicity: No engine, no transmission, no vehicle-specific complications.
• You want flexibility: If plans change, a trailer is easier to sell or repurpose than a converted van.

When a Van Makes Sense

• You want total vehicle freedom: No towing. You walk out of the door and you're mobile.
• You're camping off-road: Vans handle rough terrain better than trailers.
• You need daily vehicle functionality: Using the camper as your primary vehicle without hitching/unhitching.
• Space is less important: You're comfortable in a smaller footprint.

What Enclosed Trailer Sizes Does ECB Work With?

We've built enclosed trailer conversions in most common sizes: 6x12, 7x12, 7x14, 7x16, and custom builds up to 8.5x20. The process is the same regardless of size — we assess your needs, propose a layout, and build a system-by-system.

How Does ECB Approach Enclosed Trailer Conversions?

We've converted enough enclosed trailers to know what works and what doesn't. We don't force a van-style layout into a trailer shape. Instead, we work with the rectangle to maximize livable space.

We ask about how you plan to use it (weekends vs full-time), what vehicle you're towing with, and what systems matter to you. That conversation shapes the whole build. A weekend camper trailer needs different priorities than a full-time living rig.

Every system gets tested before you take it home. Your electrical works, your plumbing doesn't leak, your heating runs, and you know how to operate everything. You're not learning the systems on the road.

How Do You Get Started with an Enclosed Trailer Conversion?

Not sure if an enclosed trailer conversion is right for you? That's what consultations are for. Tell us your budget, your tow vehicle, and how you plan to use the camper. We'll walk you through the realistic options and help you figure out if a trailer or a van makes sense for your situation.