Hello. I am re-running the plumbing in the first floor of my house in cpvc. My plan is to do first floor this year, and second floor next year. How do I tie into hot and cold galvanized lines running upstairs and also how do you hook up cpvc at the hot water heater. Thanks

The galvanized will need to be threaded or unthread at a joint which may be impossible.

Then use a galvanized pipe union. This will give you a female thread on the galvanized pipe. The union makes it so you can fit pipes flush and allows disconnection.

Then get a CPVC male adapter and glue to the cpvc.

It's best to have male threads on the CPVC. Galvanized pip can easily split CPVC female fittings.

You can drop a flex line from the CPVC. Take a look at the big box stores.

Here is a typical hot water heater installation kit.

American Water Heater at Lowe's: Universal Water Heater Installation Kit (http://www.lowes.com/lowes/lkn?action=productDetail&productId=26375-000000135-6900815&lpage=none)