how much difference in price and quality between R19 and R20 per square feet ?? & _8 [) |. w' f( j6 {. Q+ T8 {4 |$ T# _! P0 ?9 w: X5 s( O
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who can explain why use R30 for attic. * ]9 t! I& Z% q3 q7 X5 @- V / g- H/ V# \- \Thanks
1#KochFord5 E5 i5 ^" ~" t3 e# `
The higher R value, The better insulation performance. $ \8 Y! V {6 ?In winter, the hot air always floats up due to thermal buoyancy, so R value for the roof is normally higher than that for exterior wall. 7 L2 w2 c2 h! \, G) x% |' w0 [1 sHope my answer helps.