In previous posts in this series on sleeping arrangements in minka, we have looked mainly at the dedicated bedrooms found in old minka across Japan: small, close, dark spaces, often with no window, and only a small entry to the rest of the house penetrating its otherwise solid walls.

Fast-forward multiple centuries to the Shо̄wa period (Shо̄wa jidai 昭和時代, 1926 - 1989), and there is nothing in particular that could be called a ‘dedicated bedroom’ in the residential vernacular architecture of this era: the habitable rooms or ‘daytime rooms’ (hiru-ma 昼間) are all to some degree universal spaces, with sleeping being only one of their uses. Typically these rooms are characterised by tatami mat floors, built-in closets (oshi-ire 押入), and wide openings in one or two walls, infilled with thin fusuma (襖) or lattice-and-paper or lattice-and-glass shо̄ji (障子) sliding panels.

This and the photograph below show the interior of a typical Shо̄wa period (in this case 1960s) apartment. Note the large built-in closets (*oshi-ire* 押入), *tatami* mat floors, and wide openings between rooms (here the sliding *fusuma* or *shouji* panels have been removed).

Photograph of the same apartment as above, looking in the other direction towards the tiny kitchen. Either or both of the six-mat rooms would be used as a sleeping place.

This transition was driven to a significant degree by the evolution of Japanese bedding (shingu 寝具), from the primitive woven straw bags and thin boro blankets discussed in previous posts, to the modern cotton-filled futon (布団 or 蒲団). The now-common futon, and its associated storage facilities, have played a central role in the development of minka sleeping spaces.

First, a note on terminology. In English, any thin, non-sprung mattress has come to be known as a futon, which is somewhat ironic given that this was the standard and ubiquitous type of mattress found in Europe before the industrial revolution, when it was simply called ‘mattress’. In Japanese, too, futon is the name given to the thin mattress on which one sleeps (more specifically, this is called the shiki-buton 敷き布団, ‘spread futon’); but it also refers to the ‘comforter’ or ‘duvet’ placed over the body (the kake-buton 掛け蒲団, ‘cover futon’), and can additionally be used to refer to these two items together as a ‘set’.

The cotton plant (wata 綿) has been cultivated in Japan for a long time, but for most of this history the fibre (momen 木綿) was used solely for textiles (ori-mono 織物, ‘weave thing’), and the use of raw cotton (genmen 原綿) as a filling for bedding was a luxury limited to the upper classes. It was only relatively recently, with the mass-importation of cheap foreign cotton that began after the opening up of the country at the end of the Edo period (Edo jidai 江戸時代, 1603-1868) and into the Meiji period (Meiji jidai 明治時代, 1868-1912), that cotton-filled futon began to spread, eventually reaching the remotest mountain villages. But even then, houses with small, dedicated, straw-laid ‘permanent bed’ (man-nen-yuka 万年床) bedrooms that did not adopt futon could still be found in such villages. Occasions that might require tidying up the bedroom, such as a guest staying the night, were extremely rare. In the houses of poor peasants (hyaku-shou 百姓, lit. ‘hundred names’), taking up and cleaning futon was just more labour, for which there was neither the leisure, nor the necessity, nor the storage facilities. In Japan’s humid climate, futon should need to be taken up daily and aired regularly, or eventually mould will develop between the futon and the floor.

The cotton plant (*wata* 綿) with its balls of fibre (*momen* 木綿).

Despite exceptions, however, it seems safe to say that most people living under the kind of primitive sleeping conditions described by Suzuki Bokushi and Nishiyama Uzо̄ in previous posts in this series — conditions common until the mid-19th century — would have regarded cotton-filled futon as a great blessing. The old ‘permanent bed’ bedrooms, with no ventilation or light, were breeding grounds for pulmonary tuberculosis, and were targeted for elimination by the ‘lifestyle improvement movements’ (seikatsu kaizen undо̄ 生活改善運動) of the 1920s-1960s. But the material circumstances of these houses — open, drafty, and without any means of heating spaces — and the economic circumstances of their occupants, meant that improvement measures were not easily implemented.

With the advent of the cotton-filled futon, bedrooms gradually became more open, as the futon took over the role of trapping heat — previously fulfilled by bedrooms, which preserve heat within four close and solid walls — by instead holding it closer to the body. With this change, the bedroom transformed into a more comfortable and pleasant space, and such a space is also one that becomes attractive for other purposes. An alternative interpretation is that the bedroom was done away with altogether, and sleeping became a secondary nocturnal function of rooms that had other, primary purposes during the day. For these other activities to occur, however, there had to be a place to store bedding to get it out of the way, and so the closet (oshi-ire 押入) was established as the storage place for the futon.

The futon is much bulkier than the thin boro blanket it replaced, but it remains foldable; an oshi-ire depth (between post centres) of half a ken, or 91 cm, has become standard over time, as it allows enough room for futon to be folded into three and stacked.

In other cases, the shūnо̄ (収納) and nando (納戸), previously storage rooms that were also used as bedrooms, became ‘walk-in closets’, exclusively used for the storage (mono-oki 物置き, lit. ‘thing put’) of futon and other items, as their human inhabitants ‘moved out’ to sleep under warm futon in other parts of the house.