# Rafters insulation?



## funfool (Oct 5, 2012)

not enough, but some is better then nothing. If it is free or cheap use it.
For best results blow it in, can rent a machine at Home depot and buy the bags of insulation.
Would not hurt to blow it over the foam later, but very little R-value in 3/4" foam, depending on the foam, is probably r-7 or less.
But still better then nothing.


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## joecaption (Nov 30, 2011)

http://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table
The baffles are going to take up about 1-1/2" of the avalible space.
I at least add 2 X 2's to the rafters so I can at least add R-13.


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## beenthere (Oct 11, 2008)

Moved to Insulation forum.


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## Gary in WA (Mar 11, 2009)

Appears you are in Zone 4, requiring R-38 in ceilings; http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_11_par002.htm

http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_11_sec002.htm

Don't use cellulose in the cathedral areas. I would use Roxul, install full sheets on the rafters for one layer after filling cavities, if you have enough, then drywall. Or just some rips to cover the rafter edges to prevent thermal bridging, foam air-seal one layer of the cavity foam. ADA the drywall; http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

Gary


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