Our ProMaster Camper Van Conversion

We bought a relatively small and efficient RAM ProMaster bare cargo van (a US version of the popular European Fiat Ducato) and we did a simple but fully functional conversion that includes: paneling and flooring, insulation, a full electrical system with solar charging, galley with stove, fridge and sink, fresh and grey water systems, a toilet and other odds and end.

We have documented our build in a LOT of detail.  See the Table of Contents just below.  In each section I’ve tried to include 1) how we arrived at the design, 2) the details on the build or install, 3) and what the cost, weight, and labor were.

In a nutshell we wanted a camper that drives and parks like a car, is comfortable to be in, drives well on back roads, has all the essentials, gets good gas mileage with low CO2 emissions, and is completely self-sufficient.


Our ProMaster van to RV conversion

Our ProMaster van to RV conversion


Comments, questions and suggestions and ideas are most welcome — there are comment sections on every page.

Table of Contents

Planing and Design

The Build

How Well Did it Work Out?

Cost, Labor Weight?

Lifetime Fuel and Emissions

Odds and Ends

Objectives for the Conversion

We have enjoyed RVing over the years, but lost our last RV in a highway crunch.

One thing we did not enjoy about RVing was the 10 mpg gas bills and the 2 lbs per mile of CO2 emissions. So, this project is about getting back into RVing with a smaller footprint.

These are our main objectives for the conversion.

  • We wanted the fuel efficiency to be good (20+ mpg).
  • We want it to drive and park as much like a regular car as possible.
  • Comfortable beds for two without too much hassle to convert to seating.
  • We want to be able to operate independent of electrical hookups, and preferably on solar power.
  • We want the interior to feel open and pleasant to be in.
  • We want it to be able to handle rough back roads.

To try to achieve these objectives we ended up picking the RAM ProMaster cargo van, which has an efficient, lighter weight, front wheel drive layout, and relatively efficient power plant. Within the ProMaster line, we picked the shortest version that would give us just enough space for what we needed. And, after estimating what the van would weigh after the simple conversion, we picked the lowest gross weight version of the ProMaster to get the lower final drive ratio that it comes with. We kept a strict eye on adding weight and ended up well below the allowed gross weight.

Our last RV (a Coachman class B Ford van conversion) suffered a lot from the try to cram every kind of RV feature known to mankind into a tiny envelope problem. We ended up tearing out a lot of the interior and revamping it into a simpler form that put a lot of emphasis on a good bed, descent storage, and minimal cooking facilities. This made the RV a lot more useful to us — it was more open to be in, and more comfortable to live and sleep in. This was the starting point for this new RV conversion of the ProMaster — keep it simple and open and practical.

Base Vehicle

While we ended up picking the ProMaster van as the base vehicle for our conversion, there are other similar vans that are used (a much wider choice just in the last couple years).  These include the Mercedes Sprinter, Ford Transit, and the Nissan NV.  These are all similar in that they offer full standing height versions with enough room for all the essentials.

Lots of back and forth on which of the above is the best choice for a base van.  A good place to get first hand information from the owners are the online forums:

I’ve found the information and discussions on these forums to be very helpful.

There are some commercial RV’s available or coming out on the ProMaster, Sprinter, and Transit chassis. These may suit some well, and are certainly worth taking a look at, but for us they are too big, too fancy, have more “stuff” in them than we want, don’t get the gas mileage we want, and are too expensive. I think that people in Europe have more choices and might well find a commercially made Ducato or Sprinter based RV that fits well. A video that shows some of these…

There are also other more compact vans, vehicles and trailers that can be used as a base vehicle and will do even better on fuel economy.  I plan to try and cover some of these the site develops — if you have a favorite candidate, please let me know.

Questions? Comments?

Comments, questions and suggestions are most welcome — just keep them civil and no spam.

Older Comments — this site had its start as a few pages on my solar website, and that site used the Disqus comment system.  This site is done under the WordPress umbrella and they have their own comment system which I’ve decided to use.  This leaves the problem of what to do with the accumulated comments on the old site — I don’t want to drop them as there were many good comments and questions.  So, what I’ve done for now is to copy all the old comments to a page here.  You can read them (well worth doing!) but not add new comments.  If you have a question or comment that stems from the old comments, just enter it in the new comment section below.


September 11, 2015


  1. Great job with the build, I’m building a Promaster currently, and I was wondering if you considered any additional floor insulation? My insulation of choice for walls/ceiling is a first layer of reflectix followed by rigid polysio/spray foam for cracks, been debating whether I should do a layer of reflectix on the floor, or go right for the polysio and subfloor like you did.

    This has been a great source for me during the build, thanks a lot for sharing all the details.

    • Hi Mike,
      Glad to hear the site has been helpful.

      The Reflectix does not add very much R value if it does not face an airspace. That is, most of its effective R value comes from situations where one (or both) of its reflective face sheets face an airspace.

      So, unless you can figure out how to put the Reflectix in with an airspace on one side or the other of, I’d go for using polyiso, and if you want more R value, then thicker polyiso would likely be more effective than polyiso plus Reflectix.


  2. I am interested in reading more about van conversions that would work for single women who want to travel. I would LOVE a hybrid van. I’ve been looking a the Toyota Sienna as a potential conversion.

    I just spent 25 days traveling in my Prius and loved everything but putting up and taking down my tent everyday.

    • Hi Robin,

      It looks like the 2017 Sienna will be available as a hybrid (and 4WD) — good for 25 mpg. I would have hoped for a little better mpg, but certainly a really nice package.

      Some other base vehicles to think about:
      A full sized ProMaster (like mine) can get about 20 mpg if you are a bit careful about driving it — this is twice what our last class B Coachman got, so pretty good and very roomy. But it would be nice to do better.

      The ProMaster City van and the Transit Connect van are smaller than the full size ProMaster or Transit, but still a lot of room. I think they get mpg in the mid twenties. I’d guess very easy to drive and maneuver.
      There are examples of RV conversionos of these vans out there. Some examples on this page: http://www.buildagreenrv.com/diy-rv-conversions/small-van-camper-conversions/
      This is probably a pretty economical way to go as well, as you could start with a bare van as a base for the conversion.

      A Prius V might be a possibility with outstanding mpg. It would be a bit of a challenge on inside space, but I think it could be OK with a very careful layout.

      There is a special tent made to extend the space in a standard Prius a bit — its shown on this page:

      Teardrop trailers are making a comeback and seem like a good way to go.
      They can even be pulled behind a small hybrid car.

      This idea of trying to work out a practical RV that gets really good mpg is really interesting to me. I’d be glad to put anything you find in ways to get there on this site (or link to other sites that have good ideas).

      Asking your questions on the ProMaster, Transit or Sprinter forums would probably get some interesting responses.


    • Hello Robin,

      I am a single woman and went traveling for over 2 months this summer in my toyota sienna. Over 9000 miles from the west coast to the east coast. I had a couple slight camping conversions done to my toyota sienna. It would be so nice to meet another person to travel parallel with at times. I would be very interested in talking with you about this

  3. You did an amazing job with this conversion. I’ve always loved the idea of living in a small green mobile home. Thank you so much for all the tips!

  4. I just want to thank you for sharing your information. This is very helpful to me if I try to tackle something like this. I like the way you show cut-out for the window. I didn’t read about the noise inside, do I really have to install that quiet stuff like fat maxx ?

    • Hi Ronnie,
      One of the frustrating things about deciding whether to go with noise treatment or not is that is about impossible to get good data on how much good it does. So, you are left with spending several hundred dollars on noise treatment and really not knowing how much good it does.

      On my conversion the only place I used the stick on noice mat was on the inside rear fender wells.

      Just the insulation and paneling do reduce noise quite a bit and our conversion as it is is “ok”, but could be a bit better.

      I did take some noise measurements on mine here: http://www.buildagreenrv.com/our-conversion/our-promaster-camper-van-conversion-measuring-noise-levels/
      You might look this over and see what you think.
      If you can measure your noise levels before and after conversion, that would be a big help to others trying to make this decision.

      In hindsight, I would probably have paid more attention to noise reduction during the build if I were doing it over.

      I still have a few places (eg inside the sliding and back doors) that are not treated or insulated and I plan to at least insulate these, and this may bring the noise level down a bit more,

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