Engineered vs Structured Plumbing

There is a pattern in the green building which seems to repeat. Some group of public calls for change, a few analytical sorts figure out the core reasons and develop a systems approach, and the manufacturing sector comes up with the products. So far, so good – except that the analytical guy often gets forgotten. The problem with systems improvements is that it isn’t easily packaged and sold. Don’t get me wrong – I came from the manufacturing world and have great respect for the innovations brought to market by these great entrepreneurs. But I also experience the frustration of knowing that a component piece was only a piece if not designed into a whole solution.

And so it is with plumbing. There are many environmental issues concerning water - source pollution, safety of drinking water, capture of rainwater, graywater. But the one aspect which every project can impact is the amount of water consumption. Low-hanging solutions include low-water landscaping, and low-flow fixtures. The marketplace has come up with many “engineered” products to address these needs.

The more elusive goal is that of reducing system waste in both water and heat. Energy is lost and water wasted in waiting for the hot water to arrive at the fixture. Gary Klein, the eminent water efficiency expert, who just wrapped up 19 years with the California Energy Commission, has been at the forefront of advocating structured plumbing. If the basic structure of the plumbing system is not efficient, then the “engineering” of the fixtures may not be maximized. So – plumbing systems should be designed, instead of merely “roughed in.”

This isn’t any great news. The USGBC LEED system recommends structured plumbing, but without any real reference to resources. Short of living in California or attending one of Klein’s seminars, I found this terrific presentation which he has made available on-line: Water Distribution: Getting Hotter Water Faster. While I won’t presume to condense this volume of exacting information, the basic design principles include improving the delivery of hot water, improve and use the cool-down phase, and use structured plumbing.

Gaiam Shower Head

One point which Klein has made in his work is that the eventual success of a “green” plumbing system is dependent on the owner expectations and comfort. Take, for example, a “low-flow” sunflower shower head. I was recently in a house which had two such shower heads, because the owner felt the water stream from one wasn’t sufficient. A friend of his did the same, but added a wall mounted hand-held unit - which was the most effective – as one can direct a strong enough stream of water to wash out the lint between the toes!

And not to forget the impact of the shower surround on the amount of water used. It is fairly typical for people to turn on their water well before they get into the shower, partially to allow the hot water to arrive, but also to let the heat from the water warm up the cold tile surround. So a bit of well-place insulation, or even the placement and direction of a heat vent can be part of the plumbing solution.

People will protest that there is no need to conserve water, because they live in a “wet” area. Which would be fine if they were showering in collected rainwater. But the water delivered to their faucet has costs of removing impurities, transporting, and finally heating. Conservation of culinary water is not just for desert environments.

Sustainability in plumbing is about optimizing levels of systems, from a global perspective down to the choice of toilets. I urge you to tap into Gary Klein’s work, even just to appreciate the complexity of it.