Cut several holes in drywall in basement, workout room and water heater room to allow for new gas piping to be installed Drill joists to run gas line Install 2- 1” gas regulators to accommodate high pressure gas meter Install 1” TracPipe gas line from meter ,through wall into home, and through ceiling to water heater location Connect new gas piping to water heater Install service valves below tankless and reconnect water lines Run heater drain, condensation drain, & T&P drain lines to the outside Concrete around penetration holes