The ceiling in the living room shows the network of plumbing. Small copper pipes carry water and the black cast iron pipes carry waste. Plumbers and electricians drill through freshly installed studs and beams as they find a route for their pipes, conduits, and wires. Engineering calculations are used to locate areas where holes through the beams will have minimal structural impact.  Photo 8 of 10 in 9 Critical Tips to Read Before Kicking Off a Home Renovation from Dwell Home Venice: Part 13