R-30 compressed into 7 1/4″
Attic floor:
Anyone see any problem, aside from some loss of R-value, with compressing 9 1/2″ R-30 batts into 2 x 8s – ceiling is 1/2″ non-sag gyp bd. and subfloor is 3/4″ sturd-i-floor t & g.
Jeff
Attic floor:
Anyone see any problem, aside from some loss of R-value, with compressing 9 1/2″ R-30 batts into 2 x 8s – ceiling is 1/2″ non-sag gyp bd. and subfloor is 3/4″ sturd-i-floor t & g.
Jeff
A 1225-sq.-ft. detached ADU uses a sloping lot to its advantage, featuring a split-level entrance and vaulted ceilings.
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Replies
Jeff,
No problem. The result will be a higher R-value than if you had purchased 7 1/4-inch-thick insulation (although slightly lower R-value than if your cavity measured 8 1/2 inches deep).
all you need is R 30 for the ceiling? (well maybe a R20 or 25) you must be pretty far south.. I have a full R50 and I wish I hadn't been talked out of my R80. Energy is going to get a lot more expensive. You can expect things to double within 7 years easily..
All I have is 7 1/4" ;o)
Jeff
Only if you are REQUIRED to install R-30 (e.g. by code). R30 crammed into 7+ inches doesn't meet code if R30 req'd. Otherwise, no problem ... other than increased heat loss/gain. If R30 is required ... look for an alternative. You have a sub floor above this? what is the space? Attic?
Subfloor
Can you possibly afford spray foam?
Would also eliminate convection losses.