so, i installed a two story home with pex water lines and pvc drains. I need to test the pvc piping by clogging the sewer line with a balloon and pouring water into the vent lines on the roof. All drains and toilets have been capped. Now what about the tubs each on 1st and second floor.once I fill the system the water will overflow the first floor tub, No? the over flows work but fill up so what of the tubs? do I not include them and plug the drain before, is that whats usually done? confused, and local inspector is little help but requires the water pouring off the roof line as proof its up that high.

need help, don't want water everywhere

some waste and overflow tub drains come supplied with caps/plugs that you substitute for the crhome trim. most do not so you have to disconnect the trap, plug the pipe there and test.
make sure the pipes are hung well as they are heavy when full of water.
water piping we have to test to 100 PSI..

There are test kits that have a seal for the drain and overflow for testing them.