Just how often does one need a full shower or bath ?

[kristopher]

25. It isn't as wasteful of water as you might imagine.

You sit outside the tub to wash and rinse, using a ladle and hot tub water. You then use the tub for soaking.
The next day, you top up the tub before heating the water.

It is possible to be very frugal if you want.

The water quality in the tub is good for about 5 days, or longer with a circulating filter.

In areas with scarce water you can use the bath water (remember, it has no soap in it) for any number of purposes from gardening to laundry. Ours is set to drain into a small tomato and cucumber garden plot.

This is the propane convection water heater we use.


http://www.islandhottub.com/prophtr.html

We've adapted a 150 gal stock tank as the tub, but it isn't filled to that capacity - perhaps 120gal is how much we put in. You can google this for a picture:
Rubbermaid® Structural Foam Stock Tanks, 150 gal. Capacity

You'll want something pretty deep (36-42 inches) and maybe 40x40 inches horizontal dimensions. The depth should allow the tallest person to sit upright and completely submerge their shoulders by slumping just a little. Smaller people can easily lift themselves by pulling their feet in and lifting the butt a bit.

The stock tank serves as a liner and can be prettied up with a simple cedar enclosure if you like. We use locally sawn cedar boards for the lid.