Why Experts Say to Avoid Showering While the Washing Machine Is Running

Published on December 9, 2025

Running a load of laundry while showering might seem like a time-saver, but experts caution against it. Both activities compete for the same water supply, leading to potential issues like reduced water pressure and sudden temperature changes. Plumbers advise that these inconveniences can be avoided with some simple adjustments to your routine. 

Multitasking Can Cause Low Water Pressure and Temperature Drops

Depending on how your plumbing system was designed, the washing machine and shower might share a water line. “When you step into the shower, and your washing machine is looking for hot water to fill its drum, you're fighting for the same hot water at the same time,” says Chris Hunter, director of customer relations at ServiceTitan.

This is particularly common in homes with 30- or 40-gallon water heaters that are drained quickly when multiple fixtures demand hot water at the same time, says Alex Atkinson, a plumber and HVAC technician at Super Brothers.

If your water heater isn’t big enough, or your plumbing doesn’t regulate pressure well, you’ll feel it with cold water, pressure drops, or a totally uneven shower experience. 

If this happens often, consider upgrading to a larger hot water heater or a tankless hot water heater; this way, you won't run out of hot water. You can also consider a pressure-balancing valve in your shower head so that when other hot or cold knobs are turned elsewhere in the house, the pressure of your shower does not change as it equalizes temperature and pressure across all outlets.

It Can Also Raise Your Energy Bill

“If the washing machine is on the warm or hot cycle, there is no doubt that it is going to be pulling from the same hot water supply that the shower is. That can noticeably reduce the pressure or temperature of the shower. Most importantly, from an energy savings perspective, your water heater is now attempting to recover two draws simultaneously, so it’s less efficient. It may also reduce the lifespan of the unit over the long run,” says Brandon Young, CEO at Payless Power.

What the Experts Recommend

Here’s what the pros advise, including one simple fix.

• Install a pressure-balancing or thermostatic mixing valve in the shower. That keeps the water temperature steady even when someone flushes or the washing machine runs, says Nick Hendrix, general manager at Kingdom Plumbing.
• Install a smart hot water recirculation system with a booster pump to eliminate the waiting, end the waste, and enhance comfort at home.
• Check your water heater size. If it’s undersized, you might just be running out of hot water too fast. A tankless unit can solve that for good.
• Simply run the laundry after the shower, not during.