One of the biggest headaches we ran into during our build process was trying to get our walls up and keep everything as square as possible in the process. Making sure your interior walls are square and flat from the very beginning is extremely important, because it will determine how everything else lines up later.

The Ram ProMaster’s interior cargo area walls are very wavy, which made installing cabinets, shelving units and other interior fixtures challenging. We had to decide if we wanted to save as many inches of space as we could, or sacrifice a bit to have a completely square surface to work from. We went with a middle of the road approach and built out from one of the van’s outermost vertical struts. It worked out pretty well, but we’ve had some challenges along the way.



We’d recommend putting a bit of time into planning where you might need additional supports for any shelves you plan to install (see our article about planning). It will be helpful to mark these areas as well. We marked them and it was useful to have photos for reference.

Build Steps: Framing

We started by ripping a bunch of strips of 1/2 plywood into 2 1/2” studs and screwed up the horizontal struts first. We doubled up the lowest horizontal strut with two pieces of 1/2″ plywood to provide extra-solid backing for our cabinets.

Once those were up, we measured down from each of the struts on the ceiling to give us a nice reference of where they were behind the walls once we had the paneling up. Once the paneling went up, we weren’t going to be able to see them.

We were planning to add one panel every 48”. This would help with a smooth transition from one panel to the next. Of course, you could play around with this spacing if you want to be really meticulous and hide your seams behind cabinets.  Not a terrible choice, but I decided to just use some caulk/filler to hide any exposed seams.

Our vertical studs really could have been placed anywhere as well. I wasn’t 100% sure where my upper cabinets were going to end, so I didn’t have an additional stud to support the end a bit better, but the other attachment points were solid and strong enough.

Repeat for all 3 sections of the van and you’re ready to hang your paneling.

Build Steps: Paneling

We went with a 1/4” birch plywood that was nice and flexible for following the curve of the walls. As always, we used some scrap cardboard to make a pattern for the harder parts like around the wheel wells. I knew I wanted to add cedar tongue and groove planks on the ceiling and roll it down one side of the van. I wasn’t 100% sure how tall to make the paneling on that wall, but I went about half way up to where we built out the frame.

Build Steps: Furring Strips

The next mission was to cut some of the 1/4” plywood we used for the walls into furring strips. A furring strip is a long, thin strip used to level a surface in order to finish it. We would attach them to the struts on the ceiling so that we could use a finish nailer to hang the cedar. This leaves a nice clean look without a bunch of screw heads to fill. We ripped a handful of 2-3” strips and hung them up with some sheet metal screws.

The back of the van doesn’t have any struts, so we couldn’t attach anything to the ceiling without putting screws through the roof.  We went ahead and attached a piece of 1/2 plywood to the wall right above the back door that we scribed to match the curve of the ceiling. This didn’t give us much space to nail the very ends of the cedar to, but it was enough since the cedar is so light.

Finished Product:



The studs were more than enough to secure the walls and shelving units we eventually made. The paneling is fairly light-weight, easy to work with, and not too expensive.


Building out a couple of inches further from the wall could have provided that completely square surface. In hindsight, it would be beneficial as you could then, in theory, build most of your cabinets and shelves outside of the van. This is also speculation on our part since we haven’t approached the build in that way. Something to test for the next one!

In the next article, we’ll show you how to install cedar planks. Stay tuned!