Attending the code proposals meeting Tues. in Boston. revisions are being hashed out concerning better insulation. I was able to sit there and watch a tug of war between celeous (sp) , poly spray, and conventional fiber glass batts The information exchanged I learned that fiberglass effectively does not produce the rated R value. Voids incorrect installation can reduce an R-19 to being no better than R-11. What unfolded, was the polyspray and blown insulation did a BETTER job of reflecting the true r-value. New code wants to make a 2/6 wall R-21 instead of 19. Naturally Owens Corning has warehouse's full of R19. They also can manufacture a higher density R19 to meet the R21 mandate. I also learned the there are different po;y spray insinsulations one Isotherm is a water based less toxic and more flexible and dries softer The national Energy people also participated they admit to software flaws in the RESCheck and that a new version should be ready for the fall. Addressing flores over unheated cellars could require R-30 The main problem is, nation wide, still many homes are being built with 2/8 floor joist. Other purposed requirements is dealing with Duct insulation from R-5.0 to R-8.0. I actually address this issue. Saying that before we enact a code prudence would be to find out from manufactures, especially flexible duct ones, the availability of compliant product. also how soon it can be delivered to dealers in MA. Passing a code, where no one has supplies is useless and un enforceable. I also noted more emphasis should be given to eliminating leakage.