[djmack]

I want to insulate my unfinished basement ceiling for the purpose of keeping my main room above floor warmer do i use faced or unfaced insulation if faced does the paper go toward the upstairs or face the basement also i live in illinois what r value and do i have to use one that specifically says ceiling?

 

[Windows on Wash]

No need to insulated between conditioned spaces.

Spend the money on more aptly insulating the basement walls and air sealing.

Insulation between conditioned spaces is only to help abate noise.

 

[gregzoll]

Also do not forget about air sealing around outlet boxes, windows, doors, attic hatches. Those are the largest heat & cooling loss culprits out there. Only time I would insulate the underside of a floor, is if it was over a crawlspace that is non-conditioned.

 

[Gary in WA]

Treating the basement as unconditioned per code, find your zone here;http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_11_par002.htm

Insulation for floors- per zone, here; http://publicecodes.cyberregs.com/icod/irc/2009/icod_irc_2009_11_sec002.htm

Vapor retarder goes toward the warm side- up. If the basement is dry/drafty, you could cover the f.g. with a housewrap on the joist bottoms to stop air infiltration from degrading its R-value, treating it more like a crawl space; http://energy.gov/energysaver/articles/where-insulate-home
Keep in mind you may create problems with the plumbing/ducting uninsulated and colder without the heat loss from above warming them as it does now...

Gary