Cicero wrote:

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I don't know, but I should thing that a timber floor will be much
cheaper and easier to install than a suspended concrete one! Even
with insulation and nice boards....



No, it isn;tt. And its draughty as well because you have to let
underfloor spaces breathe or risk rot.


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Given that the OP already has a suspended floor it should be cheaper to
refurbish that rather than complete replacement by either infill or concrete
block and beam.

I recently replaced my suspended timber floors including the addition of
50mm insulation and the cost was about £150-00 per room - 4m x 4m approx..
The job was actually quite straightforward and caused very little
disturbance or mess.

Cic.


A lot depends on the lack of rot and damp proofing below. Sure you can
sling in new joists, lay unsulation and cover with planks, BUT that is
likley to be as expensive as a straight concrete jobbie, and, if
underlying damp issues are not sorted, itself rot in due course.