Hi there
The conservatory is this allready been built , we would really need to know what sort of floor you are putting in and or is it already laid , there are different systems , electrical ones that can be used in almost any situation under screeding under tiles under wooden floors the last one i did the customer said it is quite expensive to run thenthere is a type where you use hot water like your radiators
as for extending the conservatory will depend on the construction how old the original is to match up to and the type of roof these are the many reasons for visits we are not all bad like the high pressure guys out there the little guys are quite helpful with these things hope this is some help to you
take care
Mark
Double M Glazing