Platform Build Plans & How To

I’ve been in Florida since early January, and will be here til the end of February. Spending loads of time with Christine and David, their daughter Eve, and roommate, Ben! I was offered some work as well, so seeing as how my original Kickstarter budget was 150% off, I’m working most days and saving up for the road ahead.

David and Christine were kind enough to loan me all the appropriate power tools, along with a paint donation, to help me build a sleeping platform and storage area for my car! This will serve two purposes.

One is to prevent theft of valuable things. Car insurance doesn’t cover your belongings, and while my old Honda had a way to disable the trunk from opening, this wagon is an easy smash-and-grab job. So the platform has a locked area for valuable things.

Secondly, this way I can sleep in the back at rest stops and on roadsides without being wedged in between mountains of my shit.


Click here to view a larger file for this drawing, including all measurements. Right click and “Save As” to get the jpeg. Following are all the details and in-progress shots of this project.

> If you don’t care about the “How To,” scroll to the end for a GIF of the painting process!


– (2) 5/8″ 4’x8′ sanded plywood sheets, for supports and top panels

– (1) 1/4″ 2’x4′ sanded plywood sheet, for bottom of lockbox

– 1′ of 1/8″ paracord, for holding up the fold-out “cooking” flap from the tailgate

– (5) 2″ish hinges, for hinging small side flaps and support beam beneath

– (2) 12″ long continous (or piano) hinges, for hinging the lock box flap

– (2) 30″ long continous (or piano) hinges, for hinging the top panels

– (1) combination lock, for the lockbox

– (1) 3 1/2″ adjustable hasp, for the lockbox

– (1) box Spax screws, star head, for assembling. These self-drilling screws saved tons of time.

– (1) package of eyelets, for attaching cord to folding “cooking” panel

The total cost for these things was $120 at Home Depot, but only because I bought a piece of damaged plywood for 70% off. Without the discount, it would have been $147 more. Christine and David also had spare paint, so that saved around $25. All together, it’s about $175. In my mind, that’s paid for by 3 nights I don’t stay at a cheap motel.



I made a mockup out of cardboard to get a feel for the dimensions, and to test how much clearance all my folding panels would have inside the car. Was glad I did, because initially my storage height of 10″ made the sleeping area way too restricted. I settled on 8.5″ high, which gives me a comfortable amount of headroom.


Bought all the lumber and had my new best friend at Home Depot cut all the pieces. I laid everything out on a to-scale drawing, and brought this in to help me make the most of each sheet, and make my helpful Home Depot employee’s life easier.


Cut a slight curve on the main support beams near the trunk tailgate. Just because it looks good.

Assembled the supports. I added a hinge on the middle one for a function described below.



Added on all the main top panels (not side panels yet). Attached hinges.

The design is comprised of two separate structures, this makes it easy to remove the pieces from the trunk. Closest to the front is the lockbox with hinged lid and little hinged side panels. The main structure has the ability to hinge up in two places, a flap at the bottom can extend out past the trunk of the car when you have the tailgate open. I plan on using this as a countertop surface for cooking while camping. Additionally, if I ever go camping with someone taller than 5’6″, we could leave the tailgate open and this allows for more foot room.

I also added a hinge in the middle support beam so that when you fold up the panels, you could sit inside the car and not have to duck. Fast forward to some future moment when I am stuck in a rainstorm or something and super grateful for this.

I like these continuous hinges a lot. Less potential for pinching my precious little fingers, and it was way easier to install them and have each panel fold up to be flush with the piece underneath. And it looks sexier.


I used my cardboard model pieces to roughly trace out the contoured side panels. This was annoying because the width of the cardboard (1/8″) obviously sat differently on the wheel well bumps than the 5/8″ wood once cut. So basically just lots of back and forth to the jigsaw to cut more and more away til it fit.

These feel really fancy to me because they flip up to reveal a space to stash things, and also make the platform all custom and nice.


It’s important to note that for these to stay horizontally in line with the platform surface, they need to fit pretty snugly or they’ll flop down. For the flap on the lock box area, because they don’t rest against the passenger doors, I had to add a little 1″ long strip to prevent the flaps from falling.


These are the two pieces outside of the car, stacked.


Everything installed and the bottom panel opened.

Screen Shot 2015-02-03 at 9.33.14 AM

And then I painted it!

Detail shot. I left some panels bare wood and some with a watery blue wash. Everything was spray-painted afterwards to protect the paint and eliminate splinter danger.

Screen Shot 2015-02-03 at 9.32.10 AM

The front lockbox gets installed first, then the second section.


Lockbox detail.


End of story: I am really fucking proud of this project, and it’s going to improve my life 450% on the road. I’m liberated to sleep anywhere I want in relative safety, and camp in the car in places when it’s too cold for my 3-season tent.

(Obviously I’ll be sleeping on my camping pad and not the bare wood).


Pretty dark in the daytime with the curtains! Helpful for blocking out the blinding lights at rest stops too.


In designing and building this project, I benefitted from a few photos online of similar projects. Subarus have a weird little following and I’m definitely not the first build out the back. I also benefitted from the use of Christine and David’s tools, project space, and spare paint.

HOWEVER, I did build the entirety of the thing myself. #likeagirl

I am fortunate to have been raised by parents and teachers who showed me how to use all manner of tools, an am surrounded my makers and artists of all kinds, especially inclusive of The Flaming Lotus Girls. Point being, I recognize I was emotionally set up to succeed at building things. But not all girls and women are. Click here to see what an org in Berkeley is doing about that.

So here you go! Blueprint, steps, and general you-can-do-it-ness. Happy to field any questions if anyone attempts something similar and runs into a snag.