We have just bought a property that has a dutch barn with a concrete base with drains.Do we have to dig it out,or can we put a surface on top for an arena? Cant afford to get big boys in!!
I think you can get away with not digging it up (trying to remember something from 30odd years ago!) a riding school I used to go to used an abandoned something or other large building as an indoor and it originally had a smooth concrete floor ... I heard years later that the place had been taken over and the indoor arena now had a proper riding surface in place.
But maybe they did dig the concrete out, I don't really know!
You could possibly hire a machine for smashing up the concrete yourself
Do you compete, could you ask wherever you compete what they have under their arenas?
We're competing on Sunday if I remember I'll ask and post again (not convinced I'll remember though)
I'd talk to the supplier of your surface and see what they recommend. I know from experience of one arena that had a surface down on concrete that it never held very well and resulted in horses slipping and falling as the surface moved.