My kids take long showers. They would take even longer showers if I hadn’t taken steps to curb their shower abuse.
I started out by installing a low flow adjustable (even to the point of stopping the water) shower head kinda like this one:
that I got from Home Depot. It’s a nice little shower head; kinda small, but it has a remarkably good spray. Only problem is that the lower gallons per minute (GPM) rating means that it just takes longer for the hot water to run out, resulting in longer, not shorter showers. Then I thought I would be clever, and slightly adjust the handle, limiting the flow. There are two problems with this: the kids normally catch it and adjust the flow all the way back up, and if they didn’t catch it they would take a longer shower since the hot water would last longer. So that “trick” is out.
The next thing that I did was turn the gas water heater all the way down as soon as the water starts. This cuts down the total hot water to the size of the water heater: 30 gallons. This results in showers that are somewhere around 20 – 30 minutes. That’s all they can really get out of the 2.5 GPM shower heads. That’s still a long time and a lot of water considering that the water heater is rated at 31.1 gallons per hour (I assume that means it can heat 31.1 gallons in an hour – slightly less time to heat the 30 gallon capacity that it actually has).
My wife does something a little different – mostly because she doesn’t want to have to remember to turn the water heater back up. She washes dishes. As many as she can while the kids are in the shower. Interestingly, this accomplishes two things: it gets dishes washed, it reduces the shower time by cutting the available hot water, assuming that the dishes are all washed during the shower and not allowed to “soak” for any length of time.
The “ultimate solution”? you guessed it, turn off water heater and wash the dishes. The result is about a 15 minute shower, which is “almost right”.