how much difference between R19 and R20 insulation, need help, thanks

KochFord

how much difference in price and quality between R19 and R20 per square feet ??
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6 i9 V; H- F% j( G0 u# ?
who can explain why use R30 for attic.
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+ o9 {8 I' p# j9 k  H3 Q9 p9 WThanks

爱城飞雪

1# KochFord
The higher R value, The better insulation performance.
- l& A" n) y+ i* ~; x1 CIn 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.
) `. C4 [9 T$ LHope my answer helps.

爱城飞雪

1# KochFord
# c  n; I5 h; S& G8 ?

, n( d0 z* w6 o% R* W* G9 F# hR19 is not commonly used.

chic-yong

R值固然重要，但隔热材料更重要。即使R值相同，不同的隔热材料性能也是不一样的。

KochFord

谢谢楼上两位