Building new Shed Base Over the top of Existing Concrete Base Post your questions and get answers regarding all areas of drives, pathways and patios

[Phil the hornet]

I've been asked to build a smaller raised base for a new shed on top of an already existing larger concrete base. Do I need to break up the existing base in order to build the new one or will new concrete adhere to the existing concrete base ?
Advice welcome.
Many thanks