Is schedule 40 plastic tubing sufficient for a 30' line from my water softener to my house?
schd 40 great- at least a 1 inch line if off your water meter
sched 40 is ok to use for a waste line. it is not permitted to be used as a supply line. if you use it is not building/plumbing code approved. you must use copper pipe or pex line.
schedule 40 is the standard tubing used for all in-home plumbing purposes (unless its copper). I advise that you make sure you know exactly what you are doing before you start the project because otherwise you could have a mess on you hands if you do anything wrong...use schedule 40 and always use primer before glue on the pipes(better to be safe then sorry)