This achievement is unlocked during the ADS Heist memory.
From the beginning, follow the path forward and then left. Go past the pipes and turn right. When you get to a turning (left/right), turn right and use your scanner on the pipes. This will remove them. Follow the path round until you get to the pipe puzzle. Turn the valves as required using the heat detection app on your phone until the pipes turn entirely blue. Once they're all blue, duck into a gap just to the right of the pipes to progress.
WARNING: You must complete the puzzle and continue as above. You can also progress by shooting a lock on a gate just to the right of the gap to bypass the puzzle - this will NOT trigger this achievement so ensure you go through the gap instead of taking this method. Thanks to Erathia96 for this information.
You will then go into a repetitive loop of opening doors and trying out the corner gun. Follow the corner gun tutorial until you exit the door and you will end up in the ADS building.
Progress through the car park (stealthily or not - your choice as it will not affect this achievement) and call the lift. This will take you into the building. From here, continue up and use the next lift. From this floor, as you move forward, the guards will complain about the plumbing not working. At this point, the achievement will unlock.