Warwick wrote:

If you skip the base and put up the shed on the flat ground then for
starters it'll rot. Then it'll shift.

Whenever I have done sheds I have always used concrete blocks and load
bearing timbers. Concrete blocks spaced about 2' apart and load bearers
on top of that. Bit of polythene betwen the concrete and the timber and
bo sherunkle.

The main advantage is that air is allowed to circulate under the floor
and stop the formation of rot/mould.

There's a shed at my mums that was done this way and it's been stood
for 45+ years. She bought it scondhand and it was apparently a good 20
years old then..

shokk