I am going from a single sink in the bath to a double sink. They will be on the same counter as the old one. Will it be possible to branch off the single water lines and run it to both sinks. Also can I run the drains to the single drain all ready there.

Good morning Brad, Yes to both questions. For the water you will need to change out the old compression angle stops to 1/2" compression angle stops with double 1/4" compression outlets. Keep the old 1/2" compression nuts and reuse them. For drainage you will need a continuous waste to tie the two lavatorys together and discharge into your existing "P" trap Hope this answers your question. More questions? I'm as close as a click. Cheers, Tom