Foundations for shed or summer house.

I'm a fan of concrete pier foundations as a simple timber frame building can so easily be built on top of them. A damp proof membrane under a timber floor is generally more cost effective than a concrete slab floor, more comfortable to work on, warmer and the building is easier to insulate and heat if need be. Perhaps you're already well on your way with this project by now? Best of luck!

There are many different methods each with their own advantages/disadvantages. My preferred method is a concrete slab with a damp proof membrane. A cheaper method would be to set rows of slabs at 1.2mtrs (or less if you prefer) and lay 4x4 posts on top of these. Then you can lay counter joists on top of these. You can set the slabs down into the ground to make the floor of the shed level to the ground outside. Hope this helps. Regards, Liam.