Sad that I am, I timed myself making one of the roof sections, it took me just over an hour to put it together (this doesn't include the bottle prep). I take 4 lengths of wood, and cut out a small section at each end so that I can fit them together to create a frame. Each corner has two pilot holes drilled and two 45mm screws inserted to hold them together. Now for the fun part, each of the 'whole' bottles has a small pilot hole drilled in the bottom, and then they are drilled with a 10mm bit, this creates a hole just large enough for a standard 6ft garden cane to be inserted. The fun bit is trying to keep hold of the bottle to create the hole without it spinning round on the drill (this takes some practice LOL).
I insert a cane (for the roof I am using some that a friend's Dad grew, slightly thinner than standard canes) into the 'whole' bottle and fix this to the bottom of the frame. I then put on 4 'bottom-less' bottles and fix the top of the cane to the top of the frame. Simple. Repeat another 10 times and then you have your roof section.
4ft length with section removed
Lengths all screwed together to create frame
1st cane attached, this is in the middle of the frame