New Garden Shed and Soft Ground

Can't say I've had any problems with anything living under any of my various sheds, I just make sure it's 3 or 4" above the ground so it not sat in a puddle, but not so high that a human could hide under there. Haven't had any mice or anything other than spiders living in the shed; well some old sacks got shredded once, but I think that critter died of lead poisoning and nothing since.
If particularly worried about vermin under shed put a skirt of chicken wire around the base fasten under or to whatever you stand the shed on.

 

If you think the ground is too soft, through being 'made-up', dig out beneath slabs and fill with MOT sub base*, consolidate and firm.
www.diy.ie/departments/tarmac-mot-subbase-large-bag/5030349012414_BQ.prd
4" airgap is sufficient, it lets you get at any critters!

 

Funny you say that, the supplier offered to put skirting around 3 sides of the shed on the basis that the shed will be sitting on 10 concrete blocks. Not sure is that for aesthetics or to keep rodents out from underneath. But wonder is the skirting mote likely to get caught with raindrops splashback and lead to rotting quicker.

In terms of a paint, they had suggested a yacht type paint/varnish or something.

 

Quite a good few suggestions in the thread for a base.
Thank you all, very helpful.

The plan is to stay in the house for 5/6 years, so ultimately I only need the wooden shed to last till then, thereafter, the new owners can worry about it as we wont be taking it with us.

With that in mind, it comes down to cost. I'm already spending 1,000 euro on the shed, so keeping the base costs low would be ideal. 10 x 4 inch concrete blocks would cost me 10 euro, or as someone else suggested just get even more blocks to spread the load even wider.

The next option Id feel most comfortable with based on my lack of DIY skills, is getting a number of slabs (lets say 25 x 400mm x400mm slabs (rough estimate) at 5 euro each, is 125 euro - plus maybe 100 euro worth of sand/gravel/hardcore) digging down a few inches, levelling and adding the sand/gravel/hardcore and lay the slabs and put the concrete blocks on top.