I want to redo the piping to one bathroom plus a garden hose bib. My
neighbor has a Wirsbo tool with both 1/2" and 3/4" expanders. BTW, this is
code legal and standard practice in my County. Job is under-house with
generous workspace.

Question:

I know what to do if I were using copper. With PEX do I simply run supply
lines (hot and cold) to the vicinity of the fixtures and then change over to
copper for the risers? Do I buy a manifold and split the PEX near the
bathroom and run individual PEX lines to the fixtures? BTW, the bathroom is
being gutted and I will have access to all of the walls.
It would be nice to have no copper under the house due to freezing, although
no pipes have frozen in the last 20± years.

Please advise as to common practice.

Thanks you very much,

Ivan Vegvary