ProMaster Van Conversion Kits: A Practical Guide

Van conversion kits promise a shortcut. Instead of designing every system from scratch, sourcing hundreds of individual parts, and figuring out how everything fits together, you buy a kit that's pre-designed for your specific van model. For the RAM ProMaster, there are more kit options than ever. Some are genuinely useful. Others are overpriced parts bundles with nice packaging.

We build custom ProMaster conversions in our shop and don't sell kits ourselves. But customers ask about kits all the time, so here's an honest breakdown of what's out there, what works, and when a kit makes sense versus going custom.

What ProMaster Conversion Kits Typically Include

Kits vary widely, but most fall into a few categories based on what they cover.

Insulation and Paneling Kits: $2,000-$5,000

The most basic type. These include pre-cut insulation (often Thinsulate or similar), wall panel templates, and ceiling panels sized for your specific ProMaster wheelbase and roof height. Some include flooring underlayment and vapor-barrier material, though we'll note that we don't use vapor barriers in our builds since they can trap moisture between layers in a van where temperature swings are constant.

What you get: Pre-cut pieces that fit the ProMaster's interior contours. Saves hours of measuring and cutting. Templates for wheel wells, door frames, and window openings.

What you don't get: Any systems. No electrical, no plumbing, no cabinetry. You still need to plan and install everything else.

Electrical Kits: $2,500-$8,000

Pre-configured electrical packages that include solar panels, a charge controller, lithium batteries, an inverter, wiring harness, fuse box, and sometimes a battery monitor. Higher-end kits add a DC-DC charger and shore power inlet. The components are matched for capacity, so a 200W solar kit pairs with a 100Ah or 200Ah battery and appropriately sized wiring.

What you get: Components that are confirmed to work together. Wiring diagrams. Usually a parts list with all the connectors, terminals, and fuses you need.

What you don't get: Installation. Routing wires through a van, making clean connections, and mounting everything safely still takes real skill. Electrical mistakes cause fires. This is the one system where cutting corners has serious consequences.

Furniture and Layout Kits: $5,000-$15,000

Pre-built or flat-pack furniture modules designed for the ProMaster interior. Includes bed platforms, cabinet boxes, kitchen galley units, and sometimes countertops. Materials range from plywood and laminate to bamboo and solid wood. Some kits use a modular system where pieces connect with hardware, making them removable.

What you get: A pre-designed layout that someone has already tested for fit. Furniture pieces that (should) match the ProMaster's dimensions. Instructions for assembly and mounting.

What you don't get: Customization. If you want a different bed size, a galley on the other side, or a layout that doesn't match the kit's design, you're modifying or replacing pieces. At that point you're doing custom work with kit pricing.

Complete Conversion Kits: $15,000-$30,000+

Everything in one package: insulation, paneling, flooring, electrical, plumbing, furniture, and sometimes appliances. These are the closest thing to a "van in a box." You still need to install everything yourself, which is 200-500+ hours of work depending on complexity and your skill level.

What you get: Every component needed for a full conversion. A clear build sequence. Parts that are designed to work together in a specific layout.

What you don't get: Labor. And the layout flexibility is limited to whatever the kit manufacturer designed. Most complete kits offer only 2-3 layout options.

The ProMaster's Flat Floor Advantage

This is genuinely one of the best things about the ProMaster for kit builders. The RAM ProMaster uses a front-wheel-drive layout, which means there's no driveshaft running underneath the cargo area. The floor is flat and low, all the way across and all the way back.

The Sprinter and Transit are rear-wheel-drive (or AWD), which means they have a raised driveshaft tunnel running down the center of the floor. Every piece of flooring, every cabinet base, and every bed platform has to account for that tunnel. It complicates cuts, creates uneven surfaces, and means furniture can't sit flat without custom framing.

For kit installation, the flat floor matters in several ways:

• Insulation and subfloor: XPS foam panels lay flat without cutting around a tunnel. Faster installation, better coverage.
• Flooring: Vinyl plank or other flooring goes down in straight runs. No awkward transitions over a hump.
• Furniture mounting: Cabinet bases and bed platforms sit flat on the floor. No shimming, no custom leg lengths for different sides of the tunnel.
• Plumbing routing: Tanks and plumbing lines can run under the floor or along it without navigating around the drivetrain.
• Lower step-in height: The ProMaster's floor sits lower than the Sprinter's, making entry easier and giving you slightly more headroom for the same exterior roof height.

If you're planning a kit install, the ProMaster is genuinely the easiest platform to work with because of this flat floor. Kit manufacturers know it, and many design their kits for the ProMaster first, then adapt for other vans.

Popular ProMaster Kit Brands

Several companies make conversion kits specifically for the ProMaster. Here's what's out there. We're not endorsing any of these since we don't use or sell kits, but they're the names that come up most.

• Adventure Wagon: Modular interior systems with a focus on removability. Good if you want to switch between camper mode and cargo mode. Higher price point.
• Trail Kitchens: Galley and kitchen modules. Slide-out kitchen units that work in ProMasters. Focused specifically on the cooking system.
• Renogy / BougeRV: Electrical kits (solar, battery, inverter bundles). Not ProMaster-specific, but widely used in ProMaster builds. Good value for the components.
• Hein: Pre-cut insulation and paneling kits for specific ProMaster configurations. Saves the measuring and cutting phase.
• DIY Van Conversions (various online): Multiple smaller companies sell plans, templates, and partial kits. Quality varies enormously. Read reviews carefully.

When Kits Make Sense

Kits aren't bad. They solve a real problem: information overload. When you're starting a conversion from zero, the number of decisions is overwhelming. What insulation? What thickness? What battery chemistry? What wire gauge? A kit makes those decisions for you.

A kit is a good choice if:

• You have solid DIY skills (carpentry, basic wiring, tool comfort)
• You have 200-500 hours of free time to dedicate to the build
• You're comfortable with the kit's pre-set layout and don't need heavy customization
• Your budget is tight and you're willing to trade time for money
• You want the learning experience of building your own van
• The kit's design actually matches what you want (check this carefully before buying)

A kit is probably not the right choice if:

• You have a specific layout in mind that doesn't match available kits
• You want a high finish level (kits are designed for efficiency, not luxury finishes)
• You don't have the tools or workspace for a months-long project
• You need the van done on a schedule (DIY timelines are unpredictable)
• You're not comfortable with electrical or plumbing work
• You want professional-grade systems with proper testing and a warranty

Kit vs. Custom: Real Cost Comparison

People assume kits are dramatically cheaper than custom builds. The gap is real, but it's smaller than it looks once you account for all the variables.

The honest comparison is that a kit saves you $15,000-$30,000 on a Basic-to-Standard equivalent build, but costs you hundreds of hours and gives you a generic layout. If your time is valuable and you want something designed specifically for how you'll use the van, custom is worth the difference. If you genuinely enjoy building things and have the time, a kit gets you a functional van for less cash.

Why We Build Custom Instead of Selling Kits

We get asked this occasionally. The short answer: every customer wants something different, and kits can't accommodate that.

One person wants a massive bed and minimal kitchen because they eat out. Another wants a full galley and a smaller sleeping area because they cook every meal. Someone else needs a dedicated workspace for remote work. Another needs to fit two mountain bikes inside. A kit gives everyone the same answer to different questions.

We also stand behind our work. When we build electrical, plumbing, and cabinetry, we know it's done right because we did it. We test every system before handoff. A kit puts the installation quality in the buyer's hands, and that's where most problems happen. Connections that seem tight but aren't. Plumbing that doesn't leak until the first rough road. Electrical that works fine until it gets hot.

That said, we respect the DIY community. If you want to build your own van using a kit, go for it. Just go in with realistic expectations about the time, skill level, and finish quality involved. Check out the ProMaster conversion cost breakdown to compare kit costs against professional build costs.

Tips If You Go the Kit Route

• Confirm your wheelbase and roof height first. ProMaster comes in 118", 136", and 159" wheelbases, with standard and high roof options. Kits are specific to a configuration. Ordering the wrong one is an expensive mistake.
• Budget 20-30% above the kit price for extras. You'll need tools, hardware, sealant, wire connectors, and a dozen things the kit doesn't include. Every DIY build goes over budget. Plan for it.
• Don't skip the electrical learning. If you're installing your own electrical, understand the system completely before you start. Watch videos, read wiring diagrams, ask questions in forums. Bad wiring causes fires. This isn't a place to wing it.
• Test everything before you close up walls. Run every wire, test every connection, and pressure-test plumbing before you cover it with panels. Chasing a leak or short behind finished walls is miserable.
• Use Thinsulate for insulation. It handles moisture well and doesn't compress over time. XPS foam on the floor for thermal break and rigidity. Skip spray foam in a van. It expands unpredictably and is impossible to remove if something behind it needs service.
• Take your time on the subfloor. The ProMaster's flat floor is an advantage, but the subfloor still needs to be level, well-insulated, and properly sealed. Everything else sits on top of it. Get this right.

Frequently Asked Questions