reply to Jack_in_VA
Re: Water leak under slab
said by Jack_in_VA:That would only be true if you are talking about refrigeration tubing. Plumbing tubing is sized by ID as the chart you posted shows so 3/8" plumbing tubing has an ID of 3/8 but 3/8 refrigeration has an OD of 3/8".
There's a big difference in 1/4 (actually 1/8 id) for any distance and 3/8 (1/4 id) at the fixture itself.