Lessons from the Real World
At Duke University, Durham, N.C., the desire to install waterless and low-flow fixtures in its facilities more than 10 years ago stemmed from responsible water management but also from the convenience of being able to retrofit the fixtures with existing, rough-in dimensions, as well as for aesthetics, according to John Noonan, Duke’s vice president of Facilities Management. He says the university has progressed toward lower flow-rate fixtures as the technology has improved over the years.
Although he observes that earlier models of retrofit flush valves did not offer the flushing performance and water savings, Noonan says current technology “has drastically improved performance such that now you don’t have to sacrifice performance for low water use, and it’s being delivered at the same cost as older, higher flow models.”
To those facility managers or building owners considering a retrofit to more efficient fixtures, Noonan offers a few words of advice before taking the plunge: As with any good project execution, he says to figure out a goal, make a plan and a budget, and stick with it. To develop that plan, facility executives should conduct a water audit and figure out where the best potential for reduction is.
“It’s better to do one toilet retrofit really well than to do five retrofits on the cheap,” he says. “If you do try and cut corners, your occupants will notice, you will get more service calls, and your mechanics will hate it. Secondly, in general, don’t try and use old high-flow china and mate it with new, low-flow valves. Again, everyone will notice and no one will like it,” Noonan observes.
When retrofitting a large bathroom with a whole series of fixtures, he says a very practical tip is to retrofit all but one of the fixtures/valves in the gang. Leaving one urinal or toilet as high-flow helps reduce main waste line clogging because it lets a little more water clean out the pipes. This is particularly important in older buildings with old cast-iron pipes that may clog more easily, Noonan says.
Ryan Adrian, P.E., mechanical engineer at global architecture, design and engineering firm HDR, Lincoln, Neb., agrees and recommends that maintenance staff look for systems or modifications that allow for intervals of continuous flow to clean out pipes and deal with blockage issues that may result from low-flow fixtures.
“You don’t need a lot of flow, you just need short intervals of continuous flow,” Adrian notes. “Find a way to put water in a pipe once a week for a couple of minutes and the system should work well.”
HDR has been field testing low-flow fixtures in its headquarters office for the past year where it has been experimenting with a “hybrid” urinal from a major fixture supplier to determine if there’s any validity to the claims about pipe blockage from low-flow fixtures. The hybrid fixtures use a waterless cartridge and a solenoid valve behind it for maintenance flushing, which HDR does every 72 hours.
“What you hear a lot is that you have the pipes that back up, and they build up and they calcify inside there. This product was brought to us, and we wanted to see if it really did debunk the myth of the buildup in the pipes,” Adrian explains.
Consequently, HDR installed two hybrid units in restrooms on heavily trafficked floors (85 to 100 people) where the fixtures are sure to get a lot of use. Adrian says HDR wanted to know if the hybrid technology worked better than waterless or standard low-flow fixtures, as well as to stay on the cutting edge of available technology.
Photo: Sloan