How is a Japanese ofuro different from a regular bathtub?

frp bathroom.jpg
Soaking in a bathtub every evening is part of the way of life for many Japanese. A part for cleaning the body from the dust of the outside world, a bath before going to bed is relaxing and warms up the body to stand even a long and cold winter night.
Japanese bathrooms are built so that there is a separate area for washing hair and body before entering into a warm bath to soak and relax. Because the bath water is not used of cleansing, the tub doesn’t have to be refilled for every member of the family.
The Japanese are also masters of efficiently using space and of course they apply this skill to their bathrooms as well. Ofuro tubs are shorter in length than regular western tubs but they also have greater depth, which means one can soak in a sitting position with warm water up to their shoulders. Many ofuros come with built in benches so that you can sit in a comfortable position and enjoy your bath. In addition the smaller size not only tends to use less water but the reduced surface area keeps the water warm longer.

japanese style ofuro.gifTraditional Ofuro

western style bath.gifWestern Style Bath

best of both bath.gifPostwar Ofuro

Although traditional Japanese ofuros are made out of hinoki wood, nowadays most of bathtubs for normal homes in Japan are made of synthetic materials such as acrylic or FRP. The size of these tubs tend to fall between traditional Japanese tubs and western style tubs. FRP Ofuros and are easy to maintain, but most importantly they don’t have to be built into your bathroom, rather just placed on the floor, like a large bucket.

As mentioned above, the japanese style bathroom consists of the bathtub itself (yo-bune or ofuro) and the washing area (araiba). The araiba is an area in front of the tub equipped with a shower and a faucet and with a floor drain. The user would sit on a stool and take time soaping and scrubbing the whole body. Then he/she would use the shower – or scoop some of the water from the tub to rinse the body before entering in the ofuro.

For this reason, the bathroom itself needs to be waterproofed as if it was a large walk-in shower. These bathrooms can be realized in concrete blocks, waterproofed (FRP, asphalt, PVC sheet) and finished with tiles, wainscoting, etc.

Alternatively, in Japan it is common to use Unit baths made as a shell of FRP cladded inside with printed panels or tiles. The Unit baths are light weight and can be installed in 1 or 2 days. Another advantage is that their structure is very thin so they are compact and highly space-efficient.
Common sizes are 1300x1600mm, 1600x1600mm, 1600x2400mm, 2100x3000mm and anything in between.
Bartok design is not exporting unit baths but we are at your disposal for any question about waterproofing or creating a wet room to enjoy fully the advantages of japanese style bathing. Do not hesitate to contact iacopo at

shipping of additional accessories

Thanks Iacopo,
for the fast reply.
It has been a pleasure working with you,and we are so looking forward to enjoying these special tubs.
We will be mentioning you to all our friends that will see tubs your company makes!
Wishing you peace,

amount of water

How many gallons one of our tubs can hold?
We are trying to figure out how big of a water heater do we need.

in you case, 500liters (132 gallons) is the full volume of the tub.
You can subtract 15 gallons for the bather and another 15 if you do not want the water to overflow from top.

You can adjust the amount of water as you like.
Recently, in the land of “up to the shoulder soaking” is becoming popular the half-body bathing (keep the water up to the waist).
In this case you would be able to soak for longer periods and enjoy the minus ion atmosphere originated by the steam rising from the tub.

tub installed in Tokyo

Here are some pictures of a beautiful hinoki bathtub installed in Tokyo.
click on the pictures for an enlarged view!

hinoki wood japanese bathtub

hinoki wood japanese bathtub

hinoki wood japanese bathtub

hinoki wood japanese bathtub

hinoki tub for the West Coast

Japanese bathing

Hinoki wood tub AB grade (quarter sawn) w/ removable bench.
sizes are: L1550mm x W940mm x H735mm (ext. dim.) 640mm (deep)
this tub is built with extra thick wall planks= t50mm (bottom plank= t42mm)
This allows for a clean L corner detail while assuring solidity and waterproofing.

Tub cover with handles is split in 3 sections for easy maneuvering.

The drain fitting will be installed on field by the client to match the exixting location.

wood tub


asnaro tub for Australia

Japanese tub

A compact but well proportioned Asnaro wood tub, quater sawn.
Sizes are as follows: L1100mm x W700mm x H700mm (ext. dim.) 620mm (deep)
The apron is finished with natural oil and the joints are realized with wood dowels for a simple, natural look.
The tub is also equipped with a cover conveniently split in two halves.

soaking tub

tub construction details: sealant

I’ve been really interested in your wooden soaker tubs. I do
have questions about the tub that would help to re ensure the tub wont
leak. If all is answered, I would love to get one!!
1. what kind of joints are used for the wall panels and kind of glue. it
looks like there are many panels glued up to make the height of the walls..
2. what kind of joint is used to connect the floor with walls….
If you can anwser these question with any drawings would be great…

Thank you for your interest in our japanese soaking tubs.
Please find enclosed some pictures of our standard details. Click on the thumbnails for an enlarged view.

planks-1.jpg planks2.jpg

we laminate the wood using wood dowels and epoxy resin (+
curing agent). There are no metal parts.
Adjoining planks are cut together so the cutting angle matches perfectly.

planks3.jpg planks4.jpg

the corner joint is realized with tongue and groove + epoxy resin.
long stainless screws are used to provide extra sturdiness.

IMGP2103.jpg IMGP2430.jpg

Honestly, our tubs do not leak. If you use it regularly (everyday or every other day) your tub will work perfectly without any maintenance.
The only thing you should pay attention to is the fact that wood tubs are vulnerable to dryness. If you leave the tub unused for long periods it may crack. It is difficult to determine exactly at which point critical conditions are reached. It depends on air temperature/humidity, ventilation, heating equipment etc.
In any case, when you leave the tub unused for a week or more (let`s say 4 days or more as a doublesafe), leave 10cm of water inside and you won`t have any problem.
Do not hesitate to contact us for any question.

Knotty hinoki tub for Venice-CA

Japanese soaking

Knotty Hinoki bathtub.
The sizes are: L1320mm x W685mm x H660mm (ext. dim.) 546mm (deep)
The tub has a very simple, elegant shape with slanted short sides.
We hope that the tub will match the client`s expectations and will provide a sensorial background for his unforgettable memories of japanese hot springs…!

Japanese bath

hair in the tub

We do enjoy our hinoki tub, although we have had some minor cracking with some black growth on the outside of one of the corner joints. We’ve also found that hair and skin cells seem to stay floating on the surface even though we always shower before entering.

I am sorry you are having some problems with the tub.
About the dust staying afloat, I do not think it is a problem of the wooden tub, although chances are that when you drain the tub, small particles attach to the wood more easily than it would be in the case of an enamel or acrylic tub.

I think you can get rid of these light particles in 2 ways:
1) letting the tub overflow from the top
2) using a thin net to skim the surface of water

About the mold and cracks, please send some pictures, I`d be glad to advice.

sealant for tub

I am enjoying my tub, which is installed on a deck outside my house. I was wondering if it is OK to put some sort of sealant on my tub, like the kind of sealant one would apply to teak wood, for example. Or, should I just leave it as-is and cover it up to make sure it doesn’t age too much because of the sun, etc.

I am glad you found a good solution for the tub.
If you apply a coat on the wood note the following:
– The tub will loose its natural “soft” touch
– The tub will loose its aroma and its skin-soothing properties
– You would have to seal it inside and outside (including bottomside) to prevent unbalanced behaviour
– Due to the oils contained in the wood, the coat may not stick uniformly and may detach. Consult also with the maker of the coating product.

Generally we recommend to use it untreated or apply a natural oil to hydratate the surface of the wood.

Additionally there are also some non chemical clear wood treatments which last one year and provide extra protection against mold.

Please let me know if you need some product.
If you have a specific problem, please send pictures of the tub and the installation conditions.

Thank you. If I do not treat it, will it deteriorate more quickly than if I treat it? I like the way it is but am worried about it deteriorating. I am having a cover made for it to keep it out of the weather. However, it got quit a bit of sun last year and cracked in some places. It does not leak, and the cracks are probably natural and not a problem. I like the way it looks now that it has aged for one year. I just wanted to make sure that I’m not supposed to be treating it with something. If there is a natural oil that I should apply, please let me know.

It is not necessary to treat the tub and usually japanese people do not apply anything.
In case you want to restore the original shine you can apply our hiba oil with a cloth, like you would do waxing a pair of leather shoes.

for purchase please refer to:
and for more specific information to:

Please keep the tub protected from direct sunlight and if you cannot, leave the tub full of water to prevent dehydratation and cracks.

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