Advice with floor insulation - External office

[tornado1979]

Hi,

I'm after some advise with options to insulate my new office floor.

The office is built with concrete blocks and is double layer with 50mm cavity wall insulation, my next challenge is the floor insulation, I'm after any idea's / suggestions.

Currently I'm thinking of raising with wood 100mm in height, installing 100mm insulation inbetween, then covering with 18mm plywood would this be ok ?

Thanks in advance