I started off with an experiment with a 12″ twin foam mattress I had on hand in my house. It is a standard size of 75 x 38 inches. Obviously it is gigantic and I want to go thinner, BUT two people can fit on top. Not comfortably – but we fit!
The width in the back area ranges from 38″ near the wheel well – to 55″ in the door well. This translates to a mix between a twin (38) and full (54) size mattress. In the beginning I entertained the idea of purchasing a full size mattress and then manually cutting it to a perfect fit. Once I put this bad boy inside however, I quickly saw that I need to simply fill in the door well with some kind of foam or pillows
| URL | Price | Type | Height (in) | Packed (in) | Availability | Notes |
| ForMyTesla | 295 | tri-fold 1.5″ memory, 4.5″ high density | 6 | 38x26x18 | In Stock | use code BTG for $10 off |
| Tesmanian | 153 | tri-fold high density foam | 3 | 38x26x9 *guessing | In Stock – Ready to Ship in 1 Business Day | use Code TES10 for 10% off, or on Amazon |
| Better Habitat | 160 | roll out memory foam | 3 | 36 wide roll | In Stock | 75x36x3 |
| Linenspa Topper 2 | 40 | flat gel topper | 2 | 37.5 wide roll | In Stock | ultra plush, 4.5/57,011 37.5×74(79)x3 |
| Inofia Tri-fold 6 | 210 | tri-fold 1.5″ memory, 4.5″ high density | 6 | 38x26x18 | In Stock | thick, soft, plush, breathable 4.4/2,350 |
| Inofia Tri-fold 4 | 200 | tri-fold 1.5″ memory, 2.5″ high density | 4 | 38x26x12 | In Stock | thick, soft, plush, breathable 4.4/2,350 |
Once you know that this bed can fit a twin size mattress your options become endless. I am not absolutely sure about a traditional inner spring mattress because the rigidity may not play nicely in the thinnest part of the car. I refined my search to air and foam, and then quickly to just foam due to convenience and price. I gravitated to tri-fold styles for convenience. They come in heights of 4, 6, 8, and beyond, and are designed to fold with one seam on the top, and the other seam on the bottom. Some come with convenient carrying cases.
Next, height. I am 6’1″ (73 inches) tall and I thought standard height (75 inches) is enough. Twin XL size beds do exist which are 80 inches long (this is the length I am accustomed to at home), but I think it is overkill. I can fully stretch out my body to the max (I bunch up while sleeping) and the only thing that spilled over was a bit of pillow – which I am not concerned about. The most annoying thing about testing my 75x38x12 bed was the fact that I had to angle the bed up to the ceiling in order to push the seat back, recline a bit, and drive. It was so thick and inflexible that I obviously could not see through the rear-view. It is possible that you may run into this problem with thinner mattresses, or hey – you might want to set the back seats up. So this is why I like the tri-fold idea.
So, with all this in mind – here is my plan. Instead of going with a convenient pre-packaged item, I decided to make it more difficult and customizable. I just ordered the Inofia Tri-fold 4 which is a 78x38x6 non-standard tri-fold constructed of 1.5 inch memory foam over a 4.5 inch supportive foam base (I believe that means high density foam). It is between standard and XL lengths. Then I can add around 2 inches of additional base layer OR a topper, based on how it feels. I am a side sleeper through and through, so my one concern is getting a thicker mattress, it is way too firm, and then needing to add the topper anyway – just wasting space. Or, maybe I like the plush top, but I sink too far down so I add base support. I could buy additional foam, cut it in half if I felt like it to accommodate two different sleeper preferences, or whatever my mind comes up with. Plus I hope a topper would smooth out the seams in the bed. Seeing how large the 6″ mattresses fold up was a bit concerning, so now I have a smaller base folding dimension, and I imagine I will roll the additional foam up. So more packing options.