Wow, what a strange decision!
It impacts on so much else in the house, such as skirtings, door architraves, door thresholds and floor levels. If your floor level is close to the ground (like one step from ground level up to your front door) then you are probably already on a concrete slab which is under your timber floating floor. Existing slabs can be polished but the results with old slabs can look patchy. Sometimes they have hairline cracks and the distribution of the blue metal gravel is usually uneven at the top. I have had two clients who did this and hated the finished patchiness so much they tiled over it!
If you are not on a concrete slab then you will be on a raised timber floor supported by stumps. You will not be able to have a real concrete slab with this, but maybe some of the fake floor levelling compounds may give you a concrete look, but they always feel a bit plastic to the touch.
The best looking polished concrete floors are new slabs where the concretor knows that it will be polished and attempts to get an even mix of blue metal gravel near the top so the polished finish looks fairly uniform. You don't know how good or bad your old slab will polish up until its done. The other thing to consider is the dirt and mess. Concrete dust is fine and goes everywhere. You will need to move everything out, especially all of your electrical equipment.
You need to decide if the mess and cost provides value, or if your budget would be better spent elsewhere,
Best of luck,
Dr Retro
of Dr Retro House Calls/Dr Retro Virtual Visits
Q