Simon, before we get too carried away with floating, etc, it would help (besides the floor plan Bryan mentioned) if we knew what the conditions are around your room(s), including outside sound levels, expected inside sound levels (thrash metal drums, dig's, Fijian Bamboo drums being struck on the floor, or just flute and acoustic guitar, etc)
Here in the US a "tip-up" means all concrete construction, where they pour all floors, walls, etc, in a single stack of slabs and then use a crane to "tip up" the walls, etc. Is that pretty much the case with you, or different? Specifically, is your floor ALSO concrete, and the joists you mention poured concrete, or are they wood or steel? What about the existing walls, exactly how are they constructed and with what?
All these details are going to have an effect on isolation, since they contribute one way or another to panel stiffness, flanking noise, structural strength, and acoustics.
You're right about isolation between CR and tracking room(s), but keep in mind the "weakest link" axiom. There is no point in building rooms whose walls, floors and ceilings are good for 70 dB unless you're willing to spend a small fortune on glass and doors. Even a control room glass that uses thick, dissimilar laminated glass and costs $9000 USD, will weaken a competently built 60 dB wall. John's preference of double sliding glass doors, if chosen well and installed correctly, would probably not exceed 50 dB by themselves, if not for more air in the form of a longer path between CR and tracking room.
If, however, you have neighbors below you (or a wife that sleeps while you record) or even neighbors alongside you, then floating the floors and floating the walls on those floors, and suspending ceilings resiliently, etc, will keep the neighbors from either calling the cops or poisoning your dog
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This is at least partly because by floating everything, you cut down quite a bit on flanking noise. If you don't induce your sound into the concrete and framing of the whole building, it won't get to the next area by traveling through structure.
So, besides a floor plan, if you could clarify your situation based on the above, it will be easier to help you figure out what you really need vs. what you may not want to bother with... Steve