base for plastic shed

[sparkydave in wales]

We've been given a plastic 8x8 shed with integral floor, does anyone know what sort of support these floors need??
I have a timber frame (4x2) on four posts with timbers at 2'centres, not sure whether I need to put more timbers in, or just put ply down first to spread the loading

 

[conny]

I have a 6' x 6' Ketler shed which I have based on flagstones. I would suggest a solid plywood underbase rather than spreading the shed base over rafters.