I have no under floor heat how do i insulate to save heat under my flooring?

Question

this is a concrete floor

Answer 1

Keeping in mind that heat rises and cold falls - I would be more concerned with your loss of heat thru the ceiling/attic.  

An existing  concrete slab-on-grade floor can be protected with carpeting/rugs.  Be mindful of possible moisture build up under carpeting on concrete slab-on-grade construction.  If you have a crawl space below your floor your should first consider a vapor barrier over the soil - plastic sheeting or roofing felt.  You could also add insulation between the floor joists.  The insulation should be unfaced (no paper) and held in place with metal wires that span the joists - available from any insulation supplier.

The biggest bang for the insulation buck is above ceiling insulation.  This prevents escapes of heat and entry of cold from unconditioned attic.  Simply pile on unfaced insulation over the ceiling support structure.  Only in extreme conditions (e.g. southern FL) is it advisable to insulate the roof underside.

Answer 2

is this a wooden floor with a crawl space under it...crawl under and put up some insulation...if its a concrete slab you cant...it amazes me that you think we can give a good answer on such little info...