Replies

1. 
   Hudson Valley Carpenter | Dec 25, 2007 06:01am | #1

   http://www.owenscorning.com/foryourhome/

   I'll just start you off with a good site for information about fiberglass insulation.  Basically, what you've heard is correct.  What's overhead is more effective than what's in the walls...but it's all relative.

2. 
   gstringe | Dec 25, 2007 06:07am | #2

   Well there is such a thing as R50 of course, but whether that is what you ended up with we don't know at his point. Heat rises? Well to be more correct, hot air rises which usually makes the ceiling warmer than the walls and hence more heat transfer because of the temperature difference, so because of this and the fact that we usually have more room in the ceiling or attic, that is where the greater insulation is placed. Radiant heat doesn't necessarily go up and conductive heat doesn't necessarily go up.

   However from a purely economic standpoint, every added R number you add, the financial payback is longer than the point you started from. As an example, going from R1 to R4 might have a financial payback of 2 years but going from R4 to R7 might be 5 years. It is not a simple linear payback thing because material costs and labor costs are not linear and insulation doesn't come in only blocks of R3 or whatever.

   Here is where the formula is: http://www.eere.energy.gov/consumer/your_home/insulation_airsealing/index.cfm/mytopic=11360

   Nobody gets in to see the wizard...not nobody...not no how!