On Thursday, 10 September 2020 at 12:58:52 UTC+1, Chris Bacon wrote:
On 10/09/2020 07:07, F Murtz wrote:
Any reason why you can not make the shed smaller?
It's a prefab concrete building. While possible (I could replace bays
with timber, for instance), I'd rather not.

It will be fine. You have effectively constructed a raft rather than strip footings, so any residual out-of-balance loads will be resisted by a small bending moment the central slab, which is fine assuming your mesh goes across everything. (and probably fine even if not)

The only issue would be if you have to make any fixings into the concrete near the edges as it might spall.