Step Van Mobile Muralist Studio

[HerrSuite]

Hi all! I'm working on a step van, and I've landed here as the closest place to 'my people' I can find. I've seen a couple others floating around here, notably the_inevitable's well-documented example which has helped me figure some things out already

Okay, so I'm 5 months into wrestling with this project, and I'd love to share and get some feedback. I've never done any vehicle work before at all, and have very minimal building experience. I'm a full-time muralist, and the goal is a mobile studio that I can work inside of to do design work, then take to a job site and work out of like a work truck to paint murals. My sights are set on 'simple' and 'functional'.

I've been detailing my whole process on my blog (see signature, or go to the first post about the step van itself), but I'll put the highlights up here.

20' long 1993 GMC Grumman Olsen P-35 Step-Van

• 4,000 lbs. empty
• 253,000 original miles
• 8-cylinder 350 engine (the second in it)
• 20' from bumper to bumper, 11'2" ground to roof, 6'11" wide
• 6'10" tall and wide on the inside, 12' cargo space
• garage-style door and double rear wheels (boo)
• radio, a/c, heat
• 1 door (passenger side)
• broken gas gauge
• chipped front windshield, 1 cracked side mirror
• brand new front tires
• Needed work on the steering column, rear axle and brakes, and exhaust system in order to pass state inspection.

Cute, right? Those are the 'before' pics from December. Since then I've mostly been planning and fretting, but I've also ripped out a lot of stuff. Gone are the shelves and metal grid divider behind the driver's seat, gross seat cover, the e-track on either side, and the whole back door and half of the tracks for it (the rest were welded on and not in the way enough to worry about).


Oh yeah, I also released a herd of children with spray paint at it :biggrin: I'm going to be painting all over it anyway, so why not? (There are a lot of reasons why not, I'm already finding, but what's done is done :marshmallow

So my plans now are as follows:

• cut two windows into the walls in the back (it didn't come with the luxury of school bus windows!) I already have the glass, salvaged from a 1992, and have outlined the placement for them on the walls themselves. Just have to drop it off at the auto glass place next week.
• frame out the interior walls/floor/ceiling to hold insulation and sheathing. several questions here - obviously i won't be framing to code, so what distances should I actually worry about? and what size lumber for framing? (planned for 2x3's right now, but I feel like I can go smaller) what kind of sheathing that won't offgas formaldehyde from being next to the sun-heated aluminum wall? I know my thickest insulation should be in the floor and ceiling, but how thick?
• buy and install solar system to power desktop computer, a/c, lights, various small chargers and electronics
• find out if I can buy a mini-split small enough for this size of space - I've been told I can find one but I'm not totally convinced it'll work

A rough sketchup of the layout:

And a better sketchup of the building plan so far:

Thanks for any advice or feedback! Tried to keep this light, so there's a lot of plans/ideas I haven't mentioned, but I'll update for sure

 

[Robin97396]

That's an interesting choice, and one I've considered in the past. That should be a very durable rig for you. I'd say this is the right place for you to get suggestions of how to make your build better. It's not a bus, but close enough. Welcome.

 

[Scooternj]

If you have access to one, make your own planks out of 4x8 hardwood plywood. Then you can customize your actual thickness as well as using it for your sheathing. Even though I've only got a portable one, I plan on doing that for all my strapping and floor joists.

 

[skoolie_n00bie]

I see how fedex beats up these types of trucks...i had a half an idea to get one before i found my bus!
Cool paint job!

Welcome!

 

[Robin97396]

Grumman vans are usually from some type of government agency. They're considerably smaller than the big company delivery vans.

 

[cadillackid]

I had a GMC step van years ago for a short time.. that thing was built like a tank.. and drove about as fast as one too.. it had the 6.2 Litre Diesel in it and some type of automatic.. had a good air conditioner and since it had been used by my company as an "inter-office" delivery van it had very low miles.. I got it cheap.. then sold it to a couple guys that wanted to make a food truck out of it..

-Christopher

 

[HerrSuite]

Thanks for the responses, all!

I just got a window cut in (and the left windshield pane replaced) at long last!! As simple as it is I’m super excited because that felt like a big roadblock for moving forward with anything at all.

I’m now focusing on the framing and insulation. I am planning to insulate wall, ceiling and floor, with the bulk of the insulation on the ceiling and floor. I will go with smaller lumber on the walls to help the weight and the width of the walls (precious interior width), as well as to fit the thinner/cheaper wall insulation I’m thinking of. For the floor, I’m framing it because I assumed I wouldn’t be able to walk on insulation board alone - won’t it compress or something over time? The current floor is indeed plenty sturdy… Need to ask some insulation experts.

WALLS
I'm framing with 1.125” x 1.5" (I’m not familiar with the baffling difference between standard lumber sizes and actual measurements, so I’m just going to use the actual measurements.) These are placed for two reasons: holding up sheathing, and to make studs for some of the furniture that should be attached to the wall for stability.

I’ve made a frame around the window to make a little windowsill, but I’m unclear on whether this is necessary since I just don’t know much about the insulation: do I need the wood? can I just cut a nice hole out of the insulation and put a thin piece of wood/aluminum around the opening to cover it?

Polyiso foam board seems to be the way to go, so I’m thinking 1” in between studs and 1/2” over top to combat thermal bridging, then some kind of sheathing (still haven’t researched what’s cheap/not hideous that doesn’t off-gas - recommendations welcome! I’d prefer something wood-ish rather than plastic, but I’m flexible)

Below: passenger wall with framing, then passenger wall with framing and basic furniture placement. The left are shelves that I already own, fit nicely over the wheel well, and need to be bracketed to the wall to make sure they're stable. They'll serve as a secondary surface for tossing a bag or things waiting to be put away, as well as some storage. My 4 big batteries will sit on top of the wheel well, under these shelves. The right object is my sink (the black part) - it's a simple rectangular basin that was under-mounted previously. I'd like to under-mount it again, but don't have a construction plan for that yet.

Below: Driver wall with framing, then driver wall with framing and furniture placement, then another view to get a better sense of the sections on the left. I'll have a long standing desk for my workspace (keeping my imac here safely is a whole nother concern - it's my main work tool and I can't not include it). To the left of that is my main paint storage - a roll-out shelf based around an ikea shelf that I just purchased. I'll need to cut it down to fit on top of the wheel well, which is why it sticks up right now. There will be a 'wall' on either side of the shelves to enclose them while driving - these will be attached to the framing for stability. Next to the left is some more shelving in front of another 'wall'. This wall sections off a small area accessible only from the rear of the vehicle which will hold my small scaffolding, ladders, painting panels, etc. There will also be a small set of shelves just behind the drivers seat at the end of the long desk, to hold books. That's what the close-together framing is for at that end, to secure that to the wall as well - I haven't addd it to the model yet.

FLOOR
Currently modeled with 1.5” x 2.5” framing, no specific insulation plan yet. Apparently the real question is whether I need framing at all?? I’m guessing I should talk to some people that sell insulation. The dark gray block on the right is the pedestal for the driver's seat. The wheel wells will also be insulated.

CEILING
I got no modeled plan for the ceiling yet - kind of figured I’d get the wall and floor frames done, then make a ceiling plan before any insulation/sheathing. Currently it seems to have about an inch of insulation above a thin aluminum panel, along with two cabin lights. I assume the rivets in horizontal stripes about every 2 feet along the ceiling denote where the c-channel bracing is.

Rather than remove all of it, I’m thinking I’ll just take the lights out and cover the whole mess - my walls only go up 90% of the way because of a little curve where the ceiling meets the wall, so I’m thinking bulk the ceiling out to there by attaching insulation and some kind of cover to where I know the c-channels must be. (pretty tin ceiling? the row houses around Richmond are covered in the stuff and I have a crush on it)

 

[PigPen-SKO]

I bet the kids loved that!

 

[Mark_In_MA]

For the floor, I don't think you need any framing at all. That rigid pink foam is plenty strong enough on its own - just toss down a layer of plywood on top, and you'll never have any problems.

I have a bit of a question for the wall.
In your SketchUp, you don't really show how you're going to deal with the existing ribs and supports for the trucks metal skin. If you were looking at a top down view, you've got the metal of the van in gray, the top plate of the wooden wall, and then the green interior wall skin. That's a lot of dead space - an inch or two at least.

Rather then framing additional walls, why not take the space between the existing "studs" and fill it with rigid pink foam insulation, then just glue and screw plywood directly over that, right in to the support ribs for the truck skin. You don't have a huge truck, so it shouldn't add that much weight, it will save you a few inches on either side, and you'll be able to screw just about anything anywhere to the wall. (Most of your furniture looks like the load is on the floor anyways - the walls just keep it from sliding around.) Use some nice grade stuff, and you've got your "wood-ish" inside paneling. The paneling will also provide you with that thermal break from the metal skin.

I suggest this for a few reasons. Normal wooden studded walls need a good top and bottom plate - and there's not great attatchment points in your truck. Screwing through the sides opens up holes. Screwing through the floor opens up holes. The roof is there, but there are probably rivets or screws in the important places already. Why build a wall where the only real strength in it is at the top and bottom, when you could screw right down the edge of a solid sheet of wood? Build the inside like they did the outside - a thin(ish) panel, secured tightly around it's perimeter.

The truck is essentially a tin can - it's going to flex and rattle a little bit. The wood paneling should give it some extra strength, and quiet the ride down a bit as well.


You're going to want a way to wall off the drivers compartment of the truck too. That glass will add major heat, and I bet the cab isn't very well insulated either. Maybe a solid wall, maybe just a custom-fit blanket/curtain rod will do the trick.

I think you've got a good idea for the ceiling, don't de-construct what you don't have to, especially if you don't need the headroom. I'd pull the wires from the old 12v lights through to the new ceiling and just find some cool new LED fixtures for them.


Remember that your battery box needs to be sealed from the occupied compartment and vented to the outside.

I like the mini-split idea, but will the batteries run it? If they won't, I might look at finding/making a cubbyhole for a standard 120v house window AC. People say they tend to be cheaper in the long run. Small gas or electric space heaters are easy to come by. Remember, your room is under 100 square feet!