Structural Waste, Is There Anything That Can Be Done About It?

August 23, 2019 5 min read

The Wait Waste

It Starts When You Have To Purge Cold Water From Your Pipes Before Your Shower Begins

Referred to as Structural Waste, every building has unique plumbing behind its walls that dictates the amount of cold water that has to exit the pipes before hot water makes its way to your shower head or bath. This volume of cold water varies based on the size and length of the pipes running from the water heater to your bathroom as well as how fast it travels through your pipes.

Behavioral Waste

Hot Water Accidentally Running Down the Drain Before You Get In – The Water's Hot, But The Shower's Empty

The research shows that, on average, you’ll spend about 1 minute away from a running shower after the hot water has actually arrived. This happens because you’re completing your normal routine – turning on the shower to purge the Structural Waste (cold water) and then leaving to do something else like brushing your teeth, making the bed, using the washroom … while your waiting for your hot water to arrive. You don’t mean to waste the hot water, but like everyone else, you’re too busy to stand around waiting for your shower to get warm.  


Research shows 75% of users regularly walk away after turning their shower on and waiting for the cold water to exit; not returning until their alternate activity (shaving, brushing teeth, using washroom …) is complete. As a result about 15% of your hot water is accidentally wasted before they ever get in. read the report

Tub/Shower Combination Units

Did you know that the speed at which the cold water purges during you shower’s warm up has a big impact on the total gallons lost? That’s right, slower speeds greatly increase not only the time, but also the total volume of cold water that has to be purged.

For example low flow shower heads can increase the actual amount of structural waste you have to purge by 50% - 100%. This happens because as the water’s velocity is reduced, more heat is lost to the plumbing system and its surrounding environment as it travels through the pipes.

That’s right, as the hot water is released from the water heater and travels to the bathroom, it has to first push the cold water out of the pipes. The slower the hot water travels, the more time it has to mix with the cold water in front of it and to also give up more of its heat to the cold pipes surrounding it.  This effect produces additional amounts Structural Waste. Yes, this extra water is a little warmer than the cold coming out before it, but it's still not warm enough to comfortably shower in.  

But what if there was a way for tub/shower combo bathrooms to significantly reduce this effect by having your hot water arrive much faster while saving more water and energy than you ever thought possible? And what if all of that could be easily and  automatically done without asking the user to change their behavior or typical warm-up routine?


The Tub Spout Solution?:

The answer is simple. Purge the cold water though the tub spout. Water flows through it up to 3 times faster than through a low flow shower head. Wait times can be slashed to a handful of seconds instead of minutes and the volume of cold water wasted can be reduced by up to a half a gallon or more.

You might ask, “But what if people still walk away, won’t that waste even more water since the tub spout is flowing at up to 5 gallons per minute? And if their gone for just two extra minutes doing other things that’s 10 gallons of cold and hot water being wasted.”

The Ideal Solution

– What if the tub spout temporarily paused the flow at the precise time the hot water arrived?

Evolve's Auto-Diverting Tub Spout System does just that. Designed specifically for tub/shower combos, it automatically stops the flow from the tub spout, preventing Hot Water (both water & energy) from being wasted while no one is in the shower, as soon as the bathing temperature water arrives.

It then automatically diverts the water to a specialized shower head that begins trickling to simply and effectively let the user know their shower is now warm and waiting.

When the bather returns from their tasks (picking out clothes, making bed, shaving …) they pull a cord or push a button to activate the shower head’s normal flow, step in, and begin showering. It’s truly that simple.

If a bath is preferred, simply activate the tub spout instead. The system even automatically reset itself for the next user how it works

Contact us for a free evaluation sample

Learn more about Auto-Diverting Tub Spout System

Stand Alone Showers (no tub)

Utilizing Evolve's ShowerStart technology, either in our Evolve shower head or our TSV adapter placed between your existing shower head and pipe, eliminates the additional waste created once the hot water arrives. As the hot water reaches the shower, the flow will slow to a trickle. This trickle is just enough to let the user know the shower is ready and waiting as well as allow for any cooling water to escape if the user is distracted for an extended period of time. The Shower head will continue to trickle until the user completes their task(s). Learn more about using ShowerStart TSV in stand alone showers

More Savings Than You Ever Imagined

In addition to speeding hot water delivery, reducing the amount of cold water you have to purge and eliminating accidental hot water waste, the auto diverting tub spout system also saves by stopping tub spout leaks and providing efficient showering. In total it can save up to a whopping 16 gallons per shower taken.

Watch the Webinar : How to Combat Structural & Behavioral Waste – Reduce Your Multifamily Property's Water & Energy Use

Real Results
Save 7% or more on your entire property's water bill with our Auto Diverting Tub Spout System. This is in addition to the water savings from other plumbing devices such as low flow shower heads, sink flow restrictors and efficient toilets, etc.
– Learn how a 156-unit multifamily property in Maryland saved 785,000 gallons and more than $10,000 in water and sewer charges in the first year of use. That’s a first-year return on investment (ROI) of 109% - without even considering the additional $4,000 - $11,000 in yearly energy savings realized through a more efficient use of hot water. Read the Study
Want More Detailed Info?
To look further at our research on bather habits and gallons lost to structural and behavioral lost, we invite you to the following links:

Gary Klein : Getting into Hot Water: The New Energy Efficiency Frontier