Semi-portable building advice - Help

Headstuff

Hi, Newbie post, so please forgive my lack of knowledge. I understand that there are a lot of variables to consider in making a reply to my questions, but I'd be grateful to know if I'm at least in the right area.

I'm designing and buiding a 16-sided, 5m diameter semi-portable building and need both to keep size and weight of everything to a minimum, but also have the building obviously fit for purpose (sunhouse). It will be moved about twice a year.

So far I'm planning on using the following sized timbers, but can easily go up or down if necessary:

The circumference is made up of 16 4"x4"'s, 7 and a half feet high, 3' apart, with around a foot and a half of each inserted into a fixing frame in decking made up of 9x2's (topped with 3/4" ply) to hold each in place. I'm hoping that this structure will hold the uprights reasonably tightly.

Between the uprights I'm using 3"x2" as stressors, none of which are directly loadbearing. The frame is also strengthened by 1" ply panels to reduce torsion. Steel sheet external skin will also help with this.

Joists, 16 of. 8 Go to a central hexagon at the peak: I hoped to get away with 2"x4" for these, as the roof will be relatively light, made up of 3/4" ply panels topped with plastic roofing 'slate-look'.

So, is the above madness? Anywhere near correct in terms of load-bearing, and is there anywhere I could come down a shade?

Thanks in advance.

H

Headstuff

Sorry, in the above it's not clear that I'm talking about a raised deck.

H

smashey

While it sounds okay to me, without an engineer's input, you are better erring on the side of caution.