i cannot do that because i will not be doing it all at once.
Phase.1 is the indoor part before my new slab is laid, i will dig under the foundation to stick a piece of pipe protruding some 1-2 ft on the outside. the outside end will be capped, the inside one will be connected or just left above the concrete level to do it later.
Phase.2 is the outdoor part connecting the outside end to the prospective shed, will involve digging.
even if i used soft copper in Phase.1, joining is inevitable as i cannot do it all at once - i need the indoor part finished ASAP and the shed is a nice-to-have for the future.