Plumbing: it may not be the most stirring topic in design and construction, but fail to get it right and nothing else much matters. Probably no other built facility places more demands and complex requirements on plumbing designers and installers than the hospital. Operating around the clock in an environment requiring complete safety, sanitation, and reliability, in a variety of settings, the plumbing system is fundamental to healthcare project success. Fortunately the “wonderful world of acronyms” has come to the rescue of hard-pressed planners of late, i.e., BIM (building information modeling), with its roots in MEP planning, and the “P” in mechanical/electrical/plumbing, which has solidly benefitted from BIM. Addressing this and other current issues in healthcare facility plumbing design is the usual Build It Right cross-section of experienced project participants, responding to questions from Healthcare Building Ideas Contributing Editors Richard L. Peck and Shannon Powers-Jones.
ENGINEER
Brian Flynn
Principal, Z&F Consulting, Wayne, Pennsylvania
What are the major challenges in healthcare facility plumbing design, from an engineering standpoint?
It is obviously a more complicated challenge than it is for most commercial or office building construction. Plumbing systems are almost as expensive in healthcare facilities as mechanical systems. One recent cost-saving measure I'm seeing more of is the use plastic pipes, not just for sanitary purposes but for domestic water as well. It's about 30% less expensive to connect from hard pipes in the ceiling to various fixtures in the space using plastic pipes, and it also allows for a lot more flexibility in room layout.
Another plumbing challenge in the healthcare facility is Legionella prevention. One way to accomplish this is to run hot water tanks at 180 degrees Fahrenheit, which will eliminate Legionella. The problem with this is the mixing valves you need to deliver water at safe temperatures don't work very well-they have difficulty accommodating the temperature differences and what you often have as a result is “creep”: water temperature steadily rises during the night to the point that people taking showers first thing in the morning can have serious problems with temperatures being too hot. Our fix for this has been to install multiple hot water tanks all running at normal temperature and then each month take one offline to sanitize with very hot water.
