I feel like this is the space in a how-to article where people wax on and on about the story behind their build. I always skip past that part when I’m reading to the build steps so I can get to my project.
So in the spirit of brevity, TL:DR I had to make a road trip and decided to build a sleeping platform in my car.
1. Identify Your Needs
This might be kind of obvious, but you should think about what you need from your sleeping platform. The design portion arguably takes longer than the actual build, and is much more important. Some things to consider:
Do you want to be able to sit up? What kind of storage do you need? Do you need it to be removable? What kind of materials do you already have on hand? Most importantly, what kind of vehicle are you building for?
2. Measure, Then Measure Again
Having zero experience with carpentry or building anything, I probably measured distances I didn’t even need. I measured from the floor to the ceiling in various spots, the back of the front seats to the trunk, the width between the back doors, the height and width between the wheel wells, and anywhere else I thought might be relevant. I used these measurements to draw inumerable diagrams on paper and determine what size platform I would need.
I already had storage bins I wanted to utilize for the storage space underneath which dictated how much clearance space I needed under the platform.
3. Draw It Out
I’m terrible at drawing. My lines aren’t straight and nothing is really proportional, but I get a better idea of how things will or won’t work and I am better able to see possible problems. Just do your best to create a visual representation of what it is you are going to attempt.
Due to my lack of carpentry experience I decided on a simple design that could fold up into my trunk when not in use, that way I would still be able to use my back seats. This meant that the platform would consist of 2 separate pieces held together by metal bolts that would slide into pre-drilled holes when setting up.
Drawing helps you figure out how your pieces will fit together and what the dimensions for the various pieces will come out to be. This will also help you decide if you will need tools or if you need to have the building supply store cut wood down to size for you.
My platform design consists of a footboard, bodyboard, and hinged headboard all on supports to give structure. I decided to add a headboard to increase the length of the structure to extend over the footwells of the back seats. By creating the hinged headboard, I could move the front seats all the way up and have a longer bed than if I weren’t to utilize that space, then fold it away and move the front seats back into position when I am driving.
4. Visit Home Depot
(Or your most convenient building supplies store.) This is my favorite part! Once you’ve drawn out your design and determined the size of each piece, figure out how much plywood you will need. I looked up the sizes of plywood available at Home Depot and figured out the least amount of plywood I would need to cut out all my pieces. I determined I would only need one sheet of 8-foot long plywood (4 feet wide). Looking at other similar sleeping platforms online I decided on 3/4” plywood and opted out of marine grade or sealed wood since this structure would always be sheltered by my vehicle.
Home Depot can only cut plywood in one direction, so even though the pieces I needed are shown in the diagram on the left, what Home Depot actually cut was the diagram on the right. It was then up to me to cut the pieces down to my intended width. The boxes shown colored in were scrap.
-(1) 8-foot piece of 3/4 inch plywood
-(1) pack of 1 5/8” porch screws
-(1) Titebond III Ultimate Wood Glue
-(4) 6” Metal gate hinges
-(2) 1/4” steel pins
- (2) 2x2 wood pieces
5. Construct Pieces
The plywood was cut into my required pieces both at Home Depot and at home. The final pieces consisted of (1) 34”x 42”, (3) 7”x 36”, (1) 27”x 48”, and (1) 12”x48”.
Since there is a minimum size Home Depot can cut pieces, I had to cut a few of them myself at home. Pictured above is my first time ever using a circular saw. I’m not a magician, you too can use a circular saw as long as you are careful. Wear protective eyewear, go slowly, and apply firm pressure on the wood so it does not move. Measure everything at least twice before commiting to a cut. Maybe have your mom watch in case you cut your leg open.
After everything has been cut, I highly suggest taking it all into your car and doing a mock assembly to make sure everything fits. Do your doors and trunk close with everything in place? Do the seats fold up/down? Can you put your driver seat back as far as you like? You may have to take your pieces back and do a little trimming to make them fit better before assembling any pieces.
Once you’ve established your measurements will suffice, it’s time to start piecing it together!
6. Footboard Assembly
The footboard is the main structure your body rests on and as such should be reinforced the most. The footboard consists of the top deck (34”x42”) and 3 support pieces underneath (7”x36”) as well as the 2”x2” pieces that the headboard locks into. The top deck is 34”x42” because 34” is the length from the back of my back seats to the trunk when the back seats are upright and my car is 42” wide between the wheel wells. The support pieces are 7” tall because the bins I wanted to use were 6” tall. This number will change depending on how tall you want your storage and how much headroom you want on your sleeping platform.
Notice the 3 support pieces are longer than the top deck by about 2”. This is because that is where the headboard rests to connect to the bodyboard. The metal pins slide through the headboard into pre-drilled holes in the 2x2s to hold the pieces together.
To ensure a sound structure, I glued the pieces together with Titebond Wood Glue. I pushed the pieces up against a wall, utilizing the 90 degree angle of the floor and wall to make sure the pieces remained straight while the glue dried. I then used 1 5/8'“ porch screws every 6 inches to further secure the pieces together. This was probably overkill in terms of stability but I wanted to make sure the footboard was not going to collapse while I was asleep on it.
I chose not to brace between the supports because I wanted to be able to put the storage bin in the picture on the right underneath the platform. In the end it was too long and I went with shorter bins, but the footboard has been very sturdy regardless.
7. Bodyboard Assembly
The bodyboard/headboard were a bit easier to assemble, consisting of only the 2 pieces connected by 4 gate hinges. The bodyboard is 27”x48” because the distance between the footboard and the top of my back seats when laid flat is 27” and my trunk is 48” wide between the back doors. The headboard is 14”x48”, longer than i intended because I decided not to cut off the last 2” of the plywood. 14” is the distance between the bodyboard and the back of my front seats.
To assemble, make sure the boards are aligned properly and do not fully tighten the hinge screws until all hinges are attached and in place. Try to place hinges at equal intervals.
Drill holes through the bodyboard that align with the holes drilled into the 2x2s on the footboard.
8. Into the Car
After all pieces are assembled you’re ready to put them all in your car. This is the make-or-break moment when you realize whether or not you’ve made a grave error somewhere along the way. You will breath a giant sigh of relief as your pieces slide into place.
My subaru’s back seats are not completely flat when laid down, but instead are slightly elevated at an angle, so my last step was finding a way to make my bodyboard lay flat when installed. I played around with small pieces of wood I had leftover, placing them underneath the top end until my level was indicating the bodyboard was laying flat. I secured these last two pieces with wood glue and more porch screws.
After discovering a friend of mine had unused carpet scraps, I decided to line my platform with carpet for added sleeping comfort and to decrease scuffing on my car interior. I used the wood glue to attach the carpet to the plywood, cut the carpet away from the hinges so they could operate freely and drilled through the carpet in the spots where the metal pins secure the head and footboards together.
Congratulations, you’ve built yourself a sleeping platform! I hope that, like me, you can surprise all your friends and relatives who were sure you did not even know how to hold a power tool!
There are a couple of things I probably would do differently if I built another platform.
-3/4” plywood was probably overkill for every piece except maybe the footboard part of the platform. I may have been able to get away with 1/2” plywood for the entire project.
-smaller bins/lower platform/more head clearance so I can sit up in bed (I can’t).
Questions? Comments? Let me know if I can assist you with your own build!