Thanks Folks,
The reason I want to change them is
1. Heat loss, No insulation under them,
2, Will have to replace the gunbarrell piping so floor boards have to com up anyway.
3. Dampness and smell, Solid floors will eliminate this.
Just a question for Bluespud,
I will have to fill approx 1.5 feet with fill, then DPC then insulation, then the concrete screed, then piping and then the final screed.
This is for a 1200 Sq foot house,
How much did yours cost. I will fill it and compact it myself.