In a residential project, what type of insulation is best for ceiling?
By code you can use R30 byt we tend to use R38 for extra support
The ceiling of a finished basement? None, unless you want sound dampening. If the basement is a heated/cooled/conditioned space, it should be treated as such with vapor barriers and insulation as required by code.
For the ceiling of the top floor of your home (unconditioned space above) you should follow local building and energy codes for your area. R38 is typical for ceilings, R21 for walls.
In my opinion i would say spray foam insulation would be the best type of insulation because not only does it insulate but it also air seals and has sound dampening qualities. for a basement it would not be required if it is conditioned living space, but could use either spray foam or fiberglass batts R30- R38, if we’retalking about a ceiling with an attic above a less expensive but very effective alternative would be blown in or a loose fill insulation although it does not air seal.