Tub/Shower Combos Increase Waste (A Lot)

3 min read

Tub/Shower Combos Increase Waste (A Lot)

Tub/shower combos are efficient in their use of space, but did you know they use significantly more water and energy - even if you're only showering? It has to do with the way we behave while waiting for hot water to arrive and the much higher flow rates delivered by tub spouts. 


Faster Warm-Ups, But A Lot More Waste

We don't like waiting for hot water.  And the best way to speed delivery and reduce wait times in a tub/shower combo is to warm your shower through the tub spout. Because tub spouts typically flow at 4-7 gallons per minute, hot water arrives in seconds instead of minutes. In fact, tub spout warm-ups are 3X faster than shower head warm-ups. 

But there's a hidden price to pay. Nearly 60% of bathers who warm their shower by using the tub spout multitask (brush teeth, shave, make bed, use washroom ...) while they're waiting for the hot water to arrive.  That means the overwhelming majority of these bathers turn on the shower, let the water run out of the tub spout and step away to do other things while waiting for their shower to become warm. When they return, they pull the diverter, step in and begin showering. But how much hot water ran down the drain while they were away?  A lot. And it's significantly more than if they had warmed the shower through the shower head. 

Research indicates the time spent away multitasking (about 2 minutes) remains consistent regardless of how fast our hot water arrives, and waits as little as 15 seconds are inconvenient enough to encourage multitasking. We're just busy during our get-ready routines and we're not going to hang around undressed, in a cold bathroom, waiting, waiting, waiting. 

When we warm-up our showers through the tub spout, 85% of the warm-up waste volume is Behavioral Waste and it occurs at a much higher flow rate (4-7 gpm). As a result, approximately 8.5 gallons of hot water are lost to Behavioral Waste during tub spout warm-ups. 

Tub Spout Warm-Up Waste 



When we warm-up our showers through the shower head, 60% of the warm-up waste volume is Behavioral Waste and it occurs at much lower flow rates (1.5 -2 gpm).  Although it takes a lot longer for the hot water to arrive Behavioral Waste is less - approximately 1.8 gallons.


Shower Head Warm-Up Waste 


Tub Diverter Spout Leaks - Even More Waste 

There's another area of signifiant waste associated with Tub/Shower Combo bathrooms and like Behavioral Waste, it's probably not one you've ever considered. It comes from leaks created by faulty tub spout diverters, and causes an additional 5 gallons of hot water waste per shower. 

Tub spout diverter leaks occur as water runs out of the tub spout while you're showering and often go unnoticed. After all, how can you tell if your feet are getting wet when they're already wet from showering?

Learn More About Tub Spout Diverter Leaks


Fast Hot Water Without Warm-Up Waste Or Tub Spout Leaks

Evolve Technologies' Auto Diverting Tub Spout System is the ideal solution for getting hot water fast without Behavioral Waste or tub spout diverter leaks. This innovative tub/shower combo system:



  • delivers hot water 3x faster than shower head warm-ups
  • automatically diverts hot water to the shower head when it arrives
  • allows the freedom to multitask while eliminating Behavioral Waste
  • thermostatically seals diverter while showering to prevent tub spout leaks
  • creates a high pressure, great feeling shower
  • saves up to 16 or more gallons of hot water per shower

  • Learn More About The Auto Diverting Tub Spout System

    Contact Us

    Contact us today to learn more about how Evolve Technologies' products can bring comfort and convenience to your shower while lowering your residence's water and energy bills.


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