What is under my concrete driveway

Base for concrete type 1 mendips or scalping compacted 200mm deph or crushed recycled concrete all are adequate for concrete finish minimum deph 100mm.

I’m not saying it’s a better answer as the answer given was pretty much correct in fact actually it probably is slightly better answer as one thing was missing and that was terram. Which should be laid on the mud before the crush/hard-core/scalpings is laid. This is for two reasons as the terram is very durable. 1, it stops hard-core being gradually pushed into the mud.2, it stops any weed growth. The answer in the original question is depending on whether it’s a detached garden and what’s on the edges of the concrete would be probably the only access point to see what was actually laid underneath. Without digging it up.breeze blocks doesn’t sound quite right to me. But the answer given was pretty good. What’s strange is the question wasn’t asking what should be underneath. The question was how doi find out what’s underneath. The best answer is actually if you think it’s wrong when you’ve paid SOMONE else to do it, then the chances are it probably is completely wrong 🤷🏼‍♂️

Personally, if you’d like to find out what is under the concrete without ripping the lot up I’d personally core drill the concrete. You will then have a idea of what is underneath

The only real way to find out what has been used as the sub-base is to take the too layer off. Or dig/excavate a few areas