With framing completed it is time for the mechanical systems to be installed. Drain lines depend on gravity to operate properly so plumbing is the first mechanical system to be installed allowing for maximum flexibility in pipe placement. Next comes heating and cooling because they have the largest ducts, and then ventilation followed by electrical. I can already tell I will be pleased with the work based on watching the skill with which the two-man team from M&R Plumbing operates. Pictured above is the laundry room washer dryer supply and drain.