Re: GBlist: Insulation ratio walls/roof

[swiftjr@NU.COM]

   Assuming you are located in a heating dominated climate and have minimal
stratification, the heat transfer (loss) through a given area of wall is no
less than (and probably higher in most cases) than the heat loss through
the same area of ceiling insulated to the same R-value (cathedral or
attic).  Of course, this is only considering conductive losses and doesn't
take into account infiltration which is a totally different beast
altogether.
      The reasons we see generally see more insulation in the ceiling are
as follows.
   The myth that heat rises (this is why air sealing is important -
   insulation usually can't be relied upon for this).
   There's more room.  Ceilings are generally the easiest and most cost
   effective (to a degree) place to beef up your R-value.
   Building codes require more insulation in the ceiling.  Just for kicks,
   ask you building inspector why this is code and see what type of
   response you get.

Hope this answers your question.
Joe Swift
Energy Crafted Home Program
Connecticut Light and Power



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