I have recently had a new toilet installed into our apartment as the pan in our old toilet had cracked. Our new toilet does not have an over spill pipe, and now the overflow pipe outside our Building is constantly dripping. What should I do?

Nothing you said makes sense. Pans are used under showers and under AC systems. Toilets do not have overflow pipes. Unless your talking about the tube that extends up from the inside of the tank? What overflow pipe is outside of the building? Are you mixing this up with the overflow pan and condensate drain from an attic AC system? No water from the toilet should be draining outside of any home or apartment ever.

It could be that turning the water off to replace the old.WC allowed grit or scale to travel along the pipe and be stuck to the ball valve washer or it could just be old and worn out. It should not be an expensive job to re-washer or replace the ball valve. I have also solved my problem from here http://www.tucsonazplumbers.com/plumbing_services/pipe_services.shtml

Do you have blond hair?

why didn’t you install new overflow pipe .Almost certainly the ball valve in the WC cistern needs re-washering or replacing. It can be solved , but depends on a number of factors, 1) is the ball valve plastic, 2)is it bottom entry or side entry to the cistern 3) is it brass and corroded etc, if you are not sure I can only suggest you call a plumber!

first off, listen, heheh people that don't know what they're talking about often come to websites to get help, no point insulting them... then again, it really pays to do all of this type of research before you make any installations. good luck, -Fishfool @ The Reef Tank