Designing Kitchens and Bathrooms - pedestle sink installation

hi, i am getting ready to install a pedestle sink in the bathroom, i know they are not practicle but that's what the misses wants. i wrote a short note about a week ago about the drain and running the drain down through the floor into the basement than installing the trap. the moderator said that was against the code. my question is what do you do with the trap? i don't think you can install the trap inside the pedestle without it being seen, or are there products out there specificly for this situation. i've been reading all the other posts and haven't seen this particular situation. their sure is a lot of info here and this is where i go first for any info. thanks in advance

I'm doing the same thing in my bathroom. The trap should be hidden for the most part inside of the pedestal section. All that should be visible is the section going into the wall.
What I am doing is I purchased a pedestal sink installation kit that comes with all new hardware and will replace the existing pieces coming out of the wall.
The trap replacement section is a smaller diameter than the original trap, but I bought an adapter that necks down from my existing 1 1/2 pipe (cast iron elbow in the wall) to the 1 1/4 dia trap tube.
The two shut off valves will be getting replaced also and when the sink is installed, all I should see is a section of the trap and the two shut-off valves.

I'm actually in the process of doing it this week so I will try to keep you informed of my process.

The plumbing is all done though and is waiting for the sink install.