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Calculating Rvalue 
PittedPrune 
4/23/2009 
I have a question. Can I calculate the RValue of insulation in a ceiling or wall, by just knowing all of the parameters?
Outdoor temp. 92 F
Attic temp. 102F
Indoor temp 84F.
Have a spot meter temp of 95.3 F where it does appear insulation is missing. All other areas are 84.5F +/ including the adjacent walls.
So final question is can I determine what the specific Rvalue is of an area without going in the attic?




Re:Calculating Rvalue 
Bob Berry 
4/24/2009 
Rvalues can at best be estimated. And even this represents a "best guess". Rvalues are steady state values, and your images are not taken under the same conditions, so the calculated value is very unlikely to match up with table values.
I would not encourage you to go down this route, you will end up with an estimated value, but you cant really use the figure for anything 


Re:Calculating Rvalue 
PittedPrune 
4/24/2009 
Bob Berry wrote: s can at best be estimated. And even this represents a "best guess". Rvalues are steady state values, and your images are not taken under the same conditions, so the calculated value is very unlikely to match up with table values.
I would not encourage you to go down this route, you will end up with an estimated value, but you cant really use the figure for anything Thank you Bob, 



