"Stormin Mormon" wrote
I live in a 14 x 65 trailer. I finally cut a small poke hole in the
ceiling,
there is 4 inches space between the top of the ceiling board, and the tin
roof. Is that enough to blow some cellulose?

That's a half inch more than typical 2"x4" wall. Keep in mind, you will
have to poke a hole to fill each cavity. First I would want to get an idea
b/4 poking holes, exactly how it's constructed, and _if_ there's already
insulation there. You should be able to reach about an R-15 value using this
stuff (sold widely around here, your area may differ). That's not a whole
lot of insulation for ceiling, but it sure would beat none.

http://www.cocooninsulation.com/highRValue.asp?Type=B