After many years, and more money than I like to think of, our new master bathroom is useable. Just some details to be dealt with, like a window curtain and door stop. One of the additions was a LARGE soaker tub! I’ve refused to use it if it just means sending the water into the septic afterwards. This bathroom is also way down the end of the house from the hot water heater, so we have to let the water run forwhile for it to get hot.
The new plan is: a water storage tank in the back corner by the two back gardens that will be filled from this tub, via a solar powered pump. We will put water into the tub as we’re letting the shower water get hot and pump it back there. We’ll also pump up the water after a bath to it. Then the back gardens can be watered from that tank. Less water waste and less water to purchase for watering the garden.
I had a hot water problem very much yours. I installed an electric ‘on demand’ hot water heater for that bathroom and I have loved how much water it has saved and it only heats water while the tap is turned on.
Merry Christmas