Buy Wood Floor
Structural wooden Sub floor, not a necessity if your box is on hard standing but is anti slip so advisable (galvanised steel when wet is slippery) its made from 18mm thickness exterior OSB wood and this is bolted (not just lay on) to the galvanised 1.2mm steel floor which makes the unit so rigid it can be sat on gravel.
Price is as per individual units advert
Structural wooden Subfloor, not a necessity if your box is on hard standing but is anti-slip so advisable (galvanised steel when wet is slippery) is made from 18mm thickness exterior OSB wood and this is bolted (not just lay on) to the galvanised 1.2mm steel floor which makes the unit so rigid it can be sat on gravel.
OSB3 is the best form of wood to use for floors it's used by everyone in the industry it's relatively cheap and very strong however floors do require maintenance if it's getting continuously wet seal using sealant varnish or lacquer or exterior paint.
Full details below
OSB3 is a versatile and durable building board. Its construction is similar to that of Plywood, with opposing orientation of wood fibers that creates rigidity and strength. OSB has superb load-bearing properties, excellent cross-dimensional stability, and an attractive wood patterned finish, its glue also repels insects. 80% of flat roofs now use osb for more case studies of its uses click NORBORD
We bolt this into threaded sections of the floor which makes the floor very rigid and enables the floor to be replaced easily.
Boxes With the structural floor in place are so strong they can be put on grass or gravel. Our boxes are the only boxes rigid enough to enable you to do this. please note that even though the weight is spread very loose gravel will settle and the unit may need to be re-leveled if this happens.
We can also supply wooden floors none structural just drop in at cost which is £25 per board we will cut to fit free of charge
Our competitors don’t do structural floors as their units require concrete or slab level subbase so all their wooden floors are drop-in not fixed.