Here's the thing: Wiggle wire
Wiggle wire is a construction method usually employed for greenhouses. A specially designed C-channel aluminium extrusion is applied to the exterior of the structure and then a plastic sheet pulled over the top. Here's the magic part: wiggle wire is then wiggled into the C locking the plastic sheet in place and evenly distributing tension.
The result is a plastic wrapped building that has these fantastic zig zag seams along the outside. No punctures in the wrapping and no unsealed areas which would allow your hot and humid micro-climate to escape.
I really don't know the first thing about greenhouses or what the most efficient/sturdiest/cheapest system of assembly is. But I know this one looks amazing. A tiny engineering marvel. I love seeing a well bent wire work so hard.