Couple o' Questions (again)

[davep]

Three more plumbing questions for my evolving basement finishing project.

1. If I'm running hot/cold water lines to a full bath (sink, toilet, shower) and also to a small wet bar should I use 3/4" or 1/2" copper? The run is about 30'. Someone told me to go with 3/4" to be safe. Safe from what though, lack of water pressure? Unlikely all the fixtures would be on at one time, but maybe so and not sure what the generally accepted code might be either. Ideas?

2. I framed up to the edge of the exterior wall insulation the builder installed in the basement (the stuff the looks like aluminum foil on one side) to save some $$. I'm wondering whether I should just run the copper lines behind the stud wall and attach to the back side of the wall? Sounds easier and less likely to take a nail... (I will also still put wall plates just in case).

3. Should I put shutoff valves at the beginning of the runs ( in the unfinished) AND at the shower stall behind an access panel? Seems like that might be overkill but not sure. Also not sure what code typically is on this issue either.

Thanks once again. dp

[SharpT]

should I use 3/4" or 1/2" copper?

1/2" should be fine. Then 3/8" max supply line to toilet and sink. Then 1/2" to shower head. If you ever could possibly want or fit a sizable bathtub in the future (or a hose bib etc.), then I would run 3/4" for the 30'. Shower heads, faucets and toilets are all "low flow".

One set of shutoffs, for this 30' extension would be fine.

SharpT