How to build a wooden shed (ed.)

OK, so suggested the idea of a gym shed and wife agreed.
So, want something cheap, solid, good, cheap, big enough, and most importantly, CHEAP.
I've never built anything big before, most I've done is repair some floor joists and build a couple of small stud walls....

Would this work? Bear in mind, I want to do as much as possible myself to save money....

Dig out ground about 10cm, fill half with compacted hardcore, then put down 50mm concrete slabs, like these https://bgfencingltd.co.uk/product/granite-flags-600mm-x-600mm-x-50mm/

Build shed without floor, somehow or other ... and put down on floor a thick rubber mat (insulation and to protect floor)

Would that work? Or maybe just get a normal big shed? Idea would be to insulate the walls and ceiling a bit (not much as won't need to hold the heat, say 20mm) and have a fan heater to warm it up in winter.

Shed will need to be 220cm high inside, at least in apex, to allow punch bag and overhead presses.

Any suggestions? Is full DIY shed best? Would a concrete slab (which I will probably pay somebody to pour, maybe) be much better?

I think a tall pent shed would work best, that slopes to the front, so rear section can be used for the punch bag and weight lifting, from for access and whatever else ...

If the shed walls are lying directly on the slab, they'll rot.

I think you'd be better served to have a slab, some dwarf walls, and the shed onto those?

Brigadier said:

If the shed walls are lying directly on the slab, they'll rot.

I think you'd be better served to have a slab, some dwarf walls, and the shed onto those?

Click to expand...

Not unless he lies the panels on treated timbers and a length of dpc

Could I just put a damp membrane under the concrete slab?

jonbey said:

Could I just put a damp membrane under the concrete slab?

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Yes.......but I would also lay the frame on dpc for extra protection of the timbers

I know it is probably not very common, but would plastic "timbers" eliminate the need for damp proofing?
like these
https://www.kedel.co.uk/mixed-plast...c-lumber-mixed-plastics-ultra-150-x-50mm.html

or is that a bit pointless?

jonbey said:

I know it is probably not very common, but would plastic "timbers" eliminate the need for damp proofing?
like these
https://www.kedel.co.uk/mixed-plast...c-lumber-mixed-plastics-ultra-150-x-50mm.html

or is that a bit pointless?

Click to expand...

yeah it would, but the cost of the plastic is horrendous compared to dpc and wood.

i dont understand how recycled plastic is so expensive, its a good idea, but well over priced