Reflective insulation

Hello Tom,
The basement of our 1996 home is not insulated. We have radiant heatinstalled under our sub-floor and wood floors, with R 11 paper-facedinsulation between the stringers. Would a reflective product likeReflectix or Prodex be effective or do we need to simply add moreinsulation? Do we need to cover the stringers with the insulation orjust insulate between them?
Thanks,
Dick

Hi Dick,
I am not a big fan of reflective insulation products since they areexpensive for what little insulation they afford you (contrary to what theyclaim!)
The acid test for adequate insulation underneath radiant floors is how warmthe basement is. If it is warm, you need to add more insulation.
If this is the case, I would suggest another 3.5" of Miraflex fiberglassinsulation. Miraflex is a non-itchy version of fiberglass insulation thatis in a plastic sheathing. It would work well in this case and would go inbetween the floor joists. It does get itchy if you mess around with it fora while, but the plastic keeps the fibers away from you.
Tom