10/15/2026
Everything you wanted to know (and then some) on building cold storage. He had very little help except for emotional support (see pic 1) Please feel free to send any questions in messenger :)
Materials: approximate for a 8'x8'x6' box on concrete floor (minus floor insulation materials). This was for my build.
(16) 4'x8'x2" foam boards R Tech
(54) 2x4x8 studs
(4) 2x4x8 pressure treated boards
(~400) 3" deck screws
(200) Plastic cap 3" nails
(2) 150' rolls of HVAC tape
Storm door and door knob/deadbolt
12k BTU air conditioner (LG) and support bracket
Shoplight
2 tubes clear Caulking (clear) if needed
2 cans spray foam if needed.
Since ours was a custom build, I built out wood panels to attach the coolbot, powerstrip, and monitor to it.
See attached photos:
This is standard 2x4 framing, but I built each wall with additional California corners. Also, picture frame bracing since it was not bolted to the concrete floor of the garage and to prevent racking of the structure. I used 16" stud spacing.
Each wall was then brought in and attached to each other with 7 screws at the California corners. This was a modular build in case I decide to disassemble it.
King and Jack studs for the door and AC unit (important). For the roof I used fencing brackets with 2x4's in order to attach the foam panels to them.
Air conditioner install: we installed a support bracket due to the ~90lbs of the unit and a 2x4 installed on the wall for the 45deg legs.
Door installation: see YouTube videos.
Foam panels: I deviated from standard Coolbot suggestions and put one layer inside and the other on the outside of the studs, leaving a 3-1/2" dead air gap. Foil side on absolute outside and inside facing. If you like, use 2 panels inside and one outside, but these panels are expensive. During my recent testing, the Box would actually get down to 37deg easily with the two panels. The secret is insulating the concrete floor (use 25psi foam boards and click flooring for a hard surface). Foil tape all butt joints (I cheated on the inside corners and used caulking). It has to be airtight to work. DOT NOT USE FIBERGLASS BATTING IN THE WALLS.
Please note this is a guide for a Box inside of a garage. My completed inside floor measurements are 5' wide by 7' long. Outside is 8'-4" long by 6'-4" wide by 8' tall
