with indoor plumbing, lets say you have 40psi entering the house. The water has to travel vertically to the sinks and showers. Now I know with a foot of height equals a certain psi downforce. But If the water travels 20 feet or so upward, I'll just throw a number out there 10 psi pressure difference. Would you have 30psi reaching the sinks or showers? And would you have to calculate the amount of flow reaching the destination from the 30psi when its been reduced by the pressure difference?