No they dont, they're just 2mm ali skins over 100mm insulation, held together with self-tapping screws... it would need some sort of timber frame. I've not seen the cam-lock ones advertised

However I've just been to look at a sectional concrete workshop and I think it could be made to serve and it is cheaper... not massively so, been quoted £4848 for a 6m x 4m but it would need some additional work doing to line it. The base is definitely cheaper, been quoted £700 for a 6m x 4m 6" thick as against nearly £2,000 for 'proper' foundations.

Lookng at the way its constructed its just cast panels and although the basic full height panels are stock, they cast the rest specific to the job for openings, etc. Obviously they have moulds with movable sides. The roof is identical to what would be used for a block/brick construction except what they offer as standard is very crude and would need to be augmented.

Which got me thinking... if you've pouring concrete, how hard would it be to cast your own panels??? a wooden base, some shuttering, a 'lid' to form the indent and some strategically placed rods to create the bolt holes to pull the panels together... If you were doing it specifically, you could cast in bosses for wall mountings including fixing studs and all sorts of useful stuff... how hard can it be?

Anybody any experience with casting concrete?