Many questions I know! If I keep the water in the tub and just heat it up, how is that done? do you provide a water heater?
The weight when full of water…can you give me an approximate figure? Will my construction framer need to make the floor extra support to hold it?
I wish there was an ofuro I could try in my area! If you know of any public ones in the pacific northwestern area of USA, please let me know!
About the shape, the rectangular tubs evolved from the method of building boxes.
The round and ingot shape tubs from the manufacturing of buckets.
Therefore the shapes are different in their origin not only in the design but also in their functionality and purpose.
Ofuros have not been designed. They have been shaped by everyday use.
I think this is a splendid example of the expression “the form follows the function” expressed by the architectural modernist movement.
Said that, here I will mention some DEMERITS of the two shapes:
1) round, ingot shape: as the planks are orientated vertically and have their cross section (which is more porous) facing up: they are more prone in becoming stained on the section by black mold (but this is not always true out of the extra humid japan)
2) rectangular tubs: the corners unnecessarily hold some a larger amount of water..!
I am not sure I answered your question…
What is your budget? If you want to use it in 2 people you need at least 1500 of length.
But if you make it deeper and add internal seats… it becomes quite expensive.
Therefore I recommend to use it without seats – which enables to have a shallower tub and also use less water.
For the weight, consider that water weights 1000 Kg per cubic meter.
Therefore it depends on the sizes but a 1500x750xD600mm will hold 670 liters (670 Kg) when filled to the rim.
This translates in 120 p/sf so I think you would need some reinforcing if the bathroom is on the 2nd floor.
Sorry, we do not know of any public ofuro in the US (we supplied ofuros to Singapore and Hong Kong spas.)
For the question about re-heating the water, please check FAQ 71.
All the Best//