How much to build this thing?
Working on the assumption plywood panels come in 2.4x1.2 sheets.
Rough dimensions are,
2.4W x 3.6L x 3.1H (1.9 to lev1, 1.2 hight of top panels.
Framing idea. I am sure more support braces are needed.
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Cladding option 2
To save on cost, the top half of the bottom would be 1/2 sheets. 2.4x0.6m
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I would expect the post need to be treated.
May not even need to be cemented into ground if made to be self bracing.
Just need a relative flat bit of ground.
Top floor needs to safely hold 200kg. Limit it to 2 people max.
Panels can probably be untreated as it is not in the ground and have a change to dry.
Also if they are not load bearing it will give it the dilapidated look once weathered 
Council guidelines says, as long as it is smaller then 10m2 no permit is required.
Hight, same distance away from boundary as it is high.
Google sketchup file here if anyone wants it.
http://sketchup.google.com/3dwarehouse/det…915a1a4c7b127c1




