Trap for pedastal sink below floor?

[flashpipe]

We're installing a pedastal sink in our newly remodeled bathroom, and I was wondering if I can run the drainpipe from the sink straight down through the floor and put the trap there or do I need to do it right where the drainpipe leaves the sink? It's easy to access from the basement, and it would be easier to hide there than trying to do it within the pedastal.

Any problems that may arise from this solution??

Thanks!!!

[Plumber2000]

Code says no more the 24" on a sink tailpiece to the trap, you can't do what your asking to do. Sorry

[flashpipe]

Alright, I've got all the plumbing coming from the floor, and it's a straight shot from the floor hole to the sink drain, so how do I incorporate the trap into the plumbing? Also, should I use pvc or brass?

Thanks!!