Thanks @imageelHi @BCS1980UK looks like a cracking good workshop! Only point I'd make is in the photo you posted showing the outside painted green it looks to me as though a small portion of the over-site projects beyond the base of the timber structure - on the right and so you may get pooling of rainwater running off the side panel and this might cause damp issues.
Given that side is partly sheltered by the nearby fence panel only a small portion would be fully exposed and hence at risk, but if it was me I'd attach some felt or similar to deflect it over the side of the concrete base and cap that with some mastic just to be sure.
I does look like a nice workspace though!
You actually read my mind, I was already searching for a solution just like that.