JAPANESE MINKA XX - POSTS

Defined functionally, a post is a slender, vertical structural member that, in a single storey building under normal conditions, transfers loads from the roof down into the ground via the foundation. The difference between a post and a column is not strictly defined, but ‘post’ is typically used to refer to relatively small-section timber, and sometimes steel, members, and ‘column’ to stone, steel, concrete, and large-section timber members, particularly in a classical context. In Japanese, all of the above are conveniently called hashira (柱).

Timber columns (with entasis) at Hōryū-ji, Nara Prefecture, 8th century.

Timber posts in a modern Japanese post-and-beam house under construction. The vertical members are temporary bracing.

A massive 240mm square hinoki (Japanese cypress) post (or column?) in a new traditional-style house.

Previous entries in this series have considered posts in minka only in relation to foundations, and in particular to the three different ways the load transfer from post to ground is achieved: setting the posts straight into the ground (hori-date 堀立て), setting them on foundation stones (ishiba-date 石場建て), or using a groundsill (土台敷き). This and the next few entries will focus on posts in their own right.

In modern Japan, posts are almost always made from either Japanese cedar (sugi, 杉, Cryptomeria japonica) or Japanese cypress (hinoki, 桧/檜, Chamaecyparis obtusa). Both species produce timber that is straight-grained, strong, and relatively soft and easy to work. In the feudal period, sumptuary laws in many parts of this country restricted the use of these timbers to the upper classes, so commoners made use of a much larger variety of species, including conifers like black pine (kuro-matsu, 黒松, Pinus thunbergii), red pine (aka-matsu, 赤松, Pinus densiflora), and hemlock (tsuga, 栂, Tsuga sieboldii), and hardwoods like the lacquer tree (urushi, 漆, Toxicodendron vernicifluum) and zelkova (keyaki, 欅, Zelkova serrata).

In the centuries before finer woodworking tools had been developed, and even in much later times in isolated mountain villages where these tools were not available, posts in minka were only minimally worked with an adze to give them reasonably flat faces. Because of the difficulty of working some species, and the poor structural characteristics of others, posts were typically far larger in section than is seen today. Sometimes bent and even forked timbers were used, giving these posts the appearance of standing trees; naturally the principle was to keep the orientation the same, i.e. with the crown end up and the root end down.

Walls in post-and-beam structures, including minka, consist of a ‘skeleton’ of loadbearing vertical and horizontal linear elements, with the spaces between them infilled or covered with largely non-structural material such as wattle and daub and timber cladding; this is opposed to ‘planar’ structures such as loadbearing masonry (and arguably also timber stud-wall), where the structural element is the whole monolithic wall itself. The Japanese term jiku-gumi (軸組), literally ‘axial assembly’ but perhaps best translated as ‘wall framing,’ refers to the assembly consisting of all the individual structural elements contained within the vertical plane of the wall: posts, tied together at their bases with ground sills, and at their heads with wall or perimeter beams, and along their length with horizontal penetrating ties (nuki, 貫) at roughly one metre centres, wedged into through-mortises in the posts. Where there are openings, this basic structural assembly is augmented by the use of lintels and sills.

A traditional Japanese ‘half-timbered’ wall under construction, showing posts, ground sills or ground beams, wall beams, three intermediate penetrating ties, and an infill of split bamboo wattle, before the application of the daub.

Close-up view of penetrating ties (nuki) wedged into through-mortises in the posts.

An obvious difference between traditional Japanese and European post-and-beam framing is that Japanese buildings did not employ the principle of the truss or quasi-truss; that is to say, they contained no ‘triangulating’ diagonal members (sujikai, 筋違) in the wall plane to brace the structure against lateral loads from wind and earthquake; instead, these forces were taken up entirely by the closely-fitted timber joints and tightly wedged penetrating ties.

A European half-timbered building, showing diagonal bracing and ‘quasi-truss’ elements.

A Japanese half-timbered temple building with no diagonal bracing elements.

There are obviously limits to what such a structural system can withstand, but up to a point it was very effective in absorbing the energy of lateral loads via the mechanism of local deformation (crushing) of the timber at the joints and tie penetrations; the surviving structure could then simply be re-plumbed and re-trued and the wedges driven further in to remove the deformation-induced play. The effectiveness of this system is heavily dependent on the high level of precision and accuracy in the joinery, which is only made possible by the use of fine saws and chisels; similar resistance to lateral loads could not be expected of earlier or more primitive minka with their crude adze-cut joints.

JAPANESE MINKA XIX - FLOOR STRUCTURE 2: RAISED FLOORS 3

Any region blessed with a high-quality building material in abundance, be that timber, stone, clay, etc., will naturally develop extraction, processing, and other value-adding commercial industries around this resource, for ‘export’ to surrounding regions and further afield. In isolated mountain villages and on remote islands, however, there may be no economical or practical way to get the resource or its products out to the wider world. This ‘landlocked’ condition, combined with the resource’s abundance, may mean that it has little or no commercial value, and so it will only be used locally, and in ways that might be considered wasteful in other circumstances, because there is no economic motivation to maximise yield and therefore profit. This has historically been the case in some regions of Japan in regards to timber, and has resulted in a floor framing method known as dai-neda-zukuri or о̄-neda-zukuri (大根太造り), ‘large joist construction’. In this method, the time-consuming work of rip-sawing and finishing many standard-dimension bearers (大引 о̄biki), joists (neda, 根太), and stumps (yuka-tsuka, 床束) is foregone in favour of fewer, larger-section joists, notched into similarly oversized, beam-like bearers which require fewer or no stumps to span between walls. Thick floorboards or planks are then fixed to these bearers and joists.

Floor framing showing large-section, beam-like bearers with few or no stumps supporting them, notched out to receive thick joists, which have been removed in this image.

An interesting comparison to о̄-neda-zukuri construction can be made with another variation in floor framing, this time a modern one only developed in recent years, known as neda-resu (根太レス) or neda-non (根太ノン) construction. Here, joists are entirely absent, replaced by 24, 28, or even 32mm thick structural plywood sheets fixed directly to a ‘lattice’ of bearers at 910mm centres in both directions.

On the left: standard modern Japanese floor framing consisting of bearers-joists-floorboards. On the right, a recent innovation, ‘joistless’ construction: thick structural plywood sheets laid directly on bi-directional bearers.

These two floor framing systems represent solutions to what are essentially inverted material and technological conditions, and could further be taken as representative of a characteristic difference between pre-industrial and industrial worlds. Whereas the conditions that gave rise to о̄-neda-zukuri method were the abundance of a resource (high quality, large-section timber) and the lack of technology required to fully exploit it (specifically the lack of technology required to extract and transport the timber economically), in the case of neda-resu construction, it is the scarcity of the resource, and the presence of the relatively sophisticated technology (peeling lathes, defect scanners, modern adhesives, hot presses, etc.) required to produce the structural plywood that makes the system both possible and economical.

JAPANESE MINKA XVIII - FLOOR STRUCTURE 2: RAISED FLOORS 2

Last week’s post presented the typical method of raised floor framing used in Japan, with joists laid on bearers and either subfloor or finish floor boards laid on top of the joists. However, for reasons of custom, sumptuary laws, economy, availability, or climate, it was common in many areas of Japan to forego floorboards and instead lay sugaki (簀掻), lattices of bamboo, reed, or timber lath, over the joists, to form the sugaki-yuka (簀掻床) or ‘lattice floor.’

In contrast to tight-fitting floorboards which prevent heat loss in winter and (most) drafts from coming up from under the floor, the open structure of the sugaki lets air pass freely in both directions. In the warmest subtropical regions of southern Japan, this could be desirable, as the sugaki allowed cool air from the shaded space between the floor and the ground to be drawn up into the house to replace warmer interior air as it rose into the roof space.

A bamboo sugaki-yuka with an inset irori hearth. From the Kawano house, originally in Ehime Prefecture, Shikoku, first half of the 17th century.

In colder areas where the sugaki-yuka was used but drafts were not welcome, the subfloor space was sealed off by infilling the gap between ground and floor level in the exterior perimeter walls with stones, then rendering the stones with daub, giving an external appearance very similar to the raised earthen floors (taka-doza-yuka, 高土座床) previously discussed.　 In these minka, the sugaki would also be covered with mushiro mats; even in warm climates, ‘local’ mats were still necessary, as lattice floors of any type, but especially bamboo lattice with its raised joints, are uncomfortable to sit on.

A bamboo sugaki-yuka partly overlaid with mushiro.

This type of floor is also seen in the upper ‘attic’ storeys of the famous gasshо̄-zukuri 合掌造り (literally ‘praying hands construction’) minka of Gifu Prefecture. The upper levels of these houses were used to raise silkworms by feeding them on mulberry leaves, requiring a well-ventilated environment.

Exterior view of gasshо̄-zukuri minka in Gifu Prefecture.

Interior of a gasshо̄-zukuri showing a timber lattice floor.

Interior of a gasshо̄-zukuri showing a bamboo lattice floor.

JAPANESE MINKA XVII - FLOOR STRUCTURE 2: RAISED FLOORS

The raised floor, or taka-yuka (高床), refers to the arrangement where the plane of the ‘living floor’ is raised above the ground level. It can describe not only the floors of residential dwellings but also those of granaries and storehouses (these non-residential structures were likely the earliest examples of the taka-yuka, due to their obvious advantages in preserving grain and other perishables from rot and vermin); it may also refer to the subtype of earthen-floored dwellings covered in last week’s post, where an earth podium is built up well above the natural ground level. Here, however, we will be primarily discussing what most people understand by the term taka-yuka: a timber floor structure of stumps, bearers and joists, with a subfloor void between the floor and the ground.

In Japan, raised floors are typically 400 to 500mm above ground level, though there are examples of floors up to a metre off the ground. Historically they have been most commonly associated with and found amongst the residences of the aristocratic and upper classes, in low-lying marshy areas and wetlands, and in the warmer and more humid regions of the country, from southern Honshū to Okinawa.

The most common floor framing (yuka-gumi 床組) construction system in modern Japanese timber-framed houses, at least until relatively recent times, is this: 90 x 90mm bearers (о̄biki 大引) spanning the area within the ground sills (dodai 土台) are laid down at a pitch (spacing) of 910mm, on timber stumps (yuka-zuka 床束) that are also 90 x 90mm in section and set at a pitch of 910mm. These stumps are tied together near their bases with thin ties (ne-garami nuki 根がらみ貫) of around 90 x 12mm, whose purpose is to prevent the stumps from slipping off their pads. To brace the floor structure in the horizontal plane, diagonal 90 x 90mm members called hi-uchi dodai (火打ち土台) are inserted in the internal corners and in other locations, in the same plane as the dodai and о̄biki. On top of and perpendicular to the bearers are laid joists (neda 根太) of around 45 x 45mm or 60 x 45mm, at a pitch of either 455mm or 303mm, depending on the floor covering/load and the strength and depth of the member. Joists are doubled under internal walls. In minka, tatami mats were usually only laid in the formal zashiki room; in this case, joist spacing was the closer 303mm, because the thin subfloor boards typically used under tatami can’t span the 455mm between joists that the 20mm-30mm thick finish floorboards used elsewhere can.

Diagram showing the elements of modern Japanese floor construction.

Rip saws (oga 大鋸) did not appear in Japan until the 14th century, and spread only slowly.

A print from the 1830s depicting men cutting a large section timber with an oga.

Before that, the only way boards and planks could be made was by splitting logs longitudinally with wedges, then finishing the surface with an adze (chо̄na 釿) or spear plane (yari-ganna 槍鉋).

Finishing boards with chо̄na.

Squaring off a log with a chо̄na.

Finishing a timber with a yari-ganna.

Relatively ready availability of large section timbers, practical limits to how thinly logs could be split, and the labour involved in finishing the boards all meant that this method tended to produce thicker planks. Adze-finished timbers have a beautiful undulating, wavelike finish, and genuinely adzed floorboards are still an option today the for those with the money; for those without, machine-finished ‘mock-adzed’ floorboards are also available.

Floorboards with a chо̄na finish.

JAPANESE MINKA XVI - FLOOR STRUCTURE 1: EARTHEN FLOORS 2

This post is a continuation from last week’s examination of earthen floors (土座床) in minka.

Even after the transition from the post-on-foundation stone method of construction to the use of a ground sill (dodai 土台堀立て柱) between posts and foundation stones, the tendency in doza-yuka dwellings was to use ‘half sills’ (han-dodai 半土台) internally, so that these members projected as little as possible above the ‘finished floor level’ of woven mats (mushiro 莚).

Doza-sumai. The earthen floors are covered with woven straw mats called mushiro.

The construction of the typical ‘floor living’ (doza-sumai 土座住まい) floor was a often more sophisticated than simply placing mats straight down on the earth. The ground was first dug out to a depth of around 100 to 200mm, then a soft ‘underlay’ layer, often of rice husks (籾殻, usually read momi-gara, but here read nuka), but alternatively some variety of straw (wara 藁) or thatch (kaya 茅), either of rice, Cyperacea species such as sedge, Miscanthus, speargrass (Imperata cylindrica) etc., or reed (yoshi or ashi, 葭), or millet husks (hie-gara or fue-gara 稗殻) was put down.

Rice husks, momi-gara.

Since straw and reed are hollow, they have an insulative effect and prevent damp, and are also unlikely to harbour fleas. Over time as they are walked on, however, the individual straws or reeds are broken and crushed, meaning both a relatively noisy floor and, as the subfloor packs down, a gradual subsidence of the finished floor level in the most trafficked areas. Because of this, and the vulnerability of these materials to insect damage, traditionally the subfloor was replaced every year.

On top of the subfloor layer went the ‘finish’ floor: mats (goza 茣蓙) of woven straw, thick mushiro (atsu-mushiro 厚莚) known as nekota or nekokata, bullrush or cattail mats (gama-mushiro 蒲莚), sedge mats (suge-mushiro 菅莚), or occasionally the rigid tatami (畳) mats that are still a characteristic feature of Japanese houses.

To minimise damage caused by flooding and the effects of ground moisture, a platform of compacted earth was sometimes built up above ground level within the perimeter of the external walls, to a height somewhat lower than or even as high as the typical timber-framed taka-yuka floor; indeed if the minka also had adjacent raised-floor areas such as a zashiki, building up the doza to this same level was logical and convenient. At first glance these raised earthen floors (taka-doza-yuka 高土座床) might appear to be timber-framed themselves, but lifting the mushiro and underlay or looking at the subfloor from the exterior would reveal an earthen base. Building up the floor in this way has the advantage that the underlay of husk or straw can be omitted, since raising the floor is similarly effective in reducing damp; it also eliminates the work of replacing the subfloor annually.

A raised doza or taka-doza-yuka.

Lifting the tatami and mushiro to reveal the raised earthen floor or taka-doza-yuka below, which is built right up to the underside of the sliding door sill (shikii, 敷居). There is no thick underlay of husks or straw; the mushiro is laid directly on the earth and serves as the underlay.

The raised earthen floor seen from the exterior of the minka, again showing how it is built up to the level of the underside of the shikii.

JAPANESE MINKA XV - FLOOR STRUCTURE 1: EARTHEN FLOORS 1

As covered back at the start of this series, the very earliest dwellings in the Japanese archaeological record had earthen floors (doza-yuka, 土座床). Somewhat later, the raised timber floor (taka-yuka, 高床) appeared, but this latter type never completely supplanted the former; the two co-existed, both as broadly separate streams and literally side-by-side, up until the 20th century, and even today the sunken entry area (genkan, 玄関) of Japanese homes is a vestigial reminder of the earthen-floored doma (土間) utility spaces that were once ubiquitous in minka, even those whose main living areas were raised-floor.

Before we go on, it is important to distinguish the doma from the subject of this post: doza-yuka-sumai (土座床住まい), or ‘earthen-floor living’, where not only utility and work activities but also seated social activities such as eating take place on the doza. The do 土 of doza means earth, and za 座 means ‘sit’ or ‘seat’.

It is reasonable to assume that the ‘modern’ doza-yuka is the direct ancestor of the ancient pit dwellings (tate-ana jūkyo 竪穴住居) of the Jо̄mon era. Broadly speaking, the traditional territory of the doza-yuka up until modern times stretched from the mountainous northern parts of the Kinki/Kansai region (the area of western Honshū encompassing the prefectures of Nara, Wakayama, Kyо̄to, О̄saka, Hyо̄go, and Shiga, and generally taken to include Mie, Fukui, Tokushima, and Tottori prefectures), through the Hokuriku region (the coastal prefectures of north western Honshū, i.e. Fukui, Toyama, Ishikawa, and Niigata), the northern parts of the old Shinshū Province (modern-day Nagano prefecture), to the Tо̄hoku region of northern Honshū, consisting of Akita, Aomori, Fukushima, Iwate, Miyagi, and Yamagata prefectures.

The fact that ‘earthen-floor living’ spread so widely and survived so long, despite obvious shortcomings such as dampness and proximity to vermin, is testament to its chief advantage: it is very effective against the bitterly cold winters experienced by all of the regions listed above. Of course, the inhabitants of earthen-floor dwellings did not sit or sleep directly on the bare earth. In both doza-yuka and taka-yuka dwellings, there is a clear, material differentiation between the doma utility area, with its bare earth floor where people would generally only stand in the course of cooking or other work, and the ‘living’ area, for eating, socialising and sleeping. Whereas in the taka-yuka dwelling this differentiation is marked by the ‘step up’ from the doma onto the timber board or bamboo covered floor of the living area, in the earthen-floored dwelling, with all areas at the same level, the boundary was often delineated with a timber sill, and the living area was differentiated from the doma by putting down layers of woven straw or reed mats called mushiro (莚), on which people could sit. On such a floor there are no drafts from below, and the mushiro are warm, soft, and pleasant underfoot. It was said that they were also very comfortable to sleep on, especially for children and the elderly, and there were many examples of minka where even after other living areas of the dwelling had been ‘upgraded’ to taka-yuka, the bedrooms remained as doza-yuka.

Image showing an earthen-floored doma in the foreground, in the midground the doza-yuka living area, spread with mushiro mats and separated from the doma by a timber sill, and in the background a taka-yuka raised-floor area separated from the doza-yuka by sliding partitions.

The same minka, here showing the doma with its posts set directly on foundation stones.

The persistence of doza-yuka might also be attributable in part to legal constraints: taka-yuka were often subject to the kind of sumptuary laws that were widespread in feudal Japan until they were lifted after the Meiji Restoration. In the Tо̄hoku region, for example, the use of board-laid floors was limited to the the formal room (zashiki, 座敷) of the village ‘officer’ or head-man’s house.

JAPANESE MINKA XIV - THE GROUND SILL

Continuing on with our ground-up (literally) examination of the structural systems of the minka, today I would like to build on the post-on-stone method covered in last week’s post to consider a later development: the dodai (土台), or ground sill.

The ground sill (or sill plate, sole plate or ground plate, as it is variously known in English) is the horizontal timber member that sits between the foundation (be that foundation stones, a stone or brick stem wall, etc.) and the posts, and transfers the load of the latter down into the former.

Image showing dodai resting on foundation stones below and supporting posts above.

While the practice of setting each post on its own foundation stone represented a significant improvement over planting the posts directly into the ground, it also has several disadvantages. For one, variability in the height of foundation stones means that the posts are not aligned at their bases and thus the posts will be of variable lengths; given the irregularity of the bearing surface of the stones, the posts are also difficult to set plumb; additionally, the open-grain post ends, though they aren’t in direct contact with the ground, still tend to draw moisture up from the stones, speeding their decay. By the use of a ground sill set on a line of foundation stones, post lengths can be made uniform, post bases can be simply cut square, and posts can be somewhat offset, i.e. placed at locations not directly over foundation stones, with the dodai acting essentially as a beam. While it is true that the dodai must still be worked somewhat so it sits level on the line of foundation stones, the degree of precision required in this isn’t as great as that needed when shaping posts to sit directly onto the stones.

The dodai also acts to tie all the posts together, thus forming a stronger overall structure. The post-to-dodai joint is formed by cutting a through-tenon known as a naga-hozo (長枘) into the post, and opening a corresponding mortise (hozo-ana, 枘穴) in the dodai; the joint can then be pinned with a timber peg (komi-sen, 込み栓), or, in more recent times, a shorter stub-tenon (tan-hozo, 短枘) and blind mortise joint may be used, reinforced by nailing a t-plate to the outside of the joint.

Three types of post-groundsill joint: on the left, a long nagahozo tenon and through-mortise; in the middle, the same but with the addition of a peg through the tenon; on the right, a stub tenon (tan-hozo) and reinforcing steel t-plate.

Close-up showing the peg (komi-sen) pinning the tenoned post into the mortised dodai.

The gap between the ground and dodai is sometimes filled in with smaller stones known as 差し石 sashi-ishi ‘insert stones’ or 覗き石 nozoki-ishi ‘peep stones’.

Sashi-ishi or nozoki-ishi used to infill the gap between the dodai and the ground.

In more recent eras and in more ‘upmarket’ townhouses and the like, foundation stones were replaced with dressed-stone strip foundations known as nunoishi (布石), which provided a continuous, flat support for the dodai.

A dodai (a) bearing on a continuous nuno-ishi stone dressed stone foundation (b).

In modern construction, the dodai rests on top of a reinforced concrete strip stem-wall which forms part of the foundation; stone, concrete, or plastic risers of 20mm or so are used between the foundation and dodai, both to protect the timber against rising damp, and to provide a ventilation gap to the subfloor space.

A modern dodai bearing on a reinforced concrete foundation, and between them a recent innovation: a continuous perforated synthetic strip serving dual purpose as both a damp-proof course and a ‘vent’ providing the necessary airflow to the subfloor space.

Given the proximity of the dodai to the ground, durable rot- and insect-resistant timbers are preferred, especially the cypress species hinoki (檜, Chamaecyparis obtusa) and hiba (檜葉,Thujopsis dolabrata, also known as asunaro アスナロ), heartwood of sugi (杉, Cryptomeria japonica), or Japanese chestnut kuri (栗, Castanea crenata).

One disadvantage of the dodai is that, when it does eventually rot out, it is more trouble to repair or replace than it is to simply cut the bases off individual posts and replace them, while leaving the rest of the post in place, as is done in the case of posts bearing directly on foundation stones. Perhaps because of this, the individual post-bearing foundation stone system survived in many places long after the advent of the dodai, with the addition of a tie (nuki 貫) threaded through mortises cut into the posts, tying them together and giving much of the structural stability of the dodai system without the dodai itself.

Image showing posts founded on individual foundation stones and structurally tied together by the addition of a nuki run through mortises in the posts. Note that the post in the foreground has had its rotten base cut off and replaced - a relatively simple operation which can be done without disturbing any of the other posts.

JAPANESE MINKA XIII - FOUNDATIONS 3

In last week’s post on ishiba-date (石場建て), the practice of using foundation stones (礎石, soseki) under timber posts, I noted that these stones are often river stones, used in their natural state without any working or dressing. If this is the case, then a problem immediately becomes apparent: how are the timber post and foundation stone to be accurately mated? Ideally, the full cross-section of the post end must bear fully on the foundation stone, for several reasons: to spread the load transmitted by the post to the stone to the maximum extent, to avoid any stress concentrations and possible localised crushing of the timber; to give the post maximum ‘grip’ on the stone to prevent any sideways movement; and to eliminate any gaps or depressions where water could enter, remain, and eventually rot out the post base. Given that timber is easier to work than stone, it makes sense to have the timber conform to the stone and not the other way around. Additionally, the work can be done by a carpenter, who is already required to build the house, whereas working stone requires a mason, i.e. bringing in an extra trade.

The task of matching the timber post end to the surface of the foundation stone might sound simple, but giving it some further thought makes it clear that it isn’t so straightforward. The post will sit on a convex section of the stone, so the post end must be made concave, and not in one but in two dimensions, i.e. a compound curve must be formed into the post end. The means by which this is achieved, with only a compass and templates, is quite ingenious.

First (B-1), a centre point is marked on the stone, two axis lines are drawn (Japanese carpenters traditionally use India ink for marking, not chalk or pencil) through this point at right angles to one another, and the ends of the axes are marked with the four cardinal points of north, south, east and west (1).

Then a template made of a thin veneer of hinoki (Japanese cypress, Chamaecyparis obtusa) is placed on the stone to align with one of the axis lines (2) and an inked compass is used to transfer the profile of the stone along this axis to the template (3).

The ‘transfer template’ is cut along the marked line to create a concave cutout (5). This concave template is then placed against another template (6) and the cut line is traced onto this ‘final template’, which is then cut (7), giving a convex cutout that describes the profile required through the centre of the post end, along one axis.

The whole process is then repeated for the other axis, giving two ‘final’ templates.

Next (B-2), the square post, with the centreline of each of its sides marked, is placed onto the foundation stone so that these centreline markings align with the two axis lines on the stone (1). A compass is used to mark the profile of the foundation stone at each face of the post onto these faces (2). The end of the post is cut square close to the profile lines (3), and a chisel is then used to remove the final material from the four faces up to the profile lines (4).

Then the first concave centreline template is placed against the post end and material is carefully chiselled out from the ‘interior’ of the post end until its profile along the relevant axis matches that of the template (5). The procedure is then repeated for the other axis using the other template (6).

Picture (7) shows a dowel inserted into holes drilled into the centrepoints of the foundation stone and post end. This is to accurately locate the post on the stone and to ensures that the post doesn’t shift off centre during construction; it likely wouldn’t be of much structural use in an earthquake.

The same procedure is used for round posts, except that four axis lines and four final templates are required instead of just two (B-3).

A carpenter, inkpot in hand, using a split-bamboo compass to transfer the profile of the foundation stone to one of the faces of the post.

JAPANESE MINKA XII - FOUNDATIONS 2

Last week’s post covered the most primitive method of foundation used in minka, the horidate-bashira method, in which timber posts are set directly into shallow excavations. It also briefly touched on a later improvement over that method: ishiba-date (石場建て), the practice of using foundation stones (礎石, soseki) under the timber posts. This week I would like to look at this method in more detail.

In many cases, the foundation stones used in minka are used in their natural state, without any working or dressing. Typically these are large, attractive river stones known as tama-ishi (玉石) or gorotaishi (ごろた石), whose edges have been rounded smooth by centuries of water action.

Natural, unworked river stones used as post foundations in a minka.

Another example, here below a raised floor.

On important buildings such as temples, the head or ‘column seat’ of the stone, that part visible above ground, would be finely worked into a circular pad, resulting in a composition very similar in appearance to the base of one of the simpler orders of classical Greek or Roman columns. With the passing of time, the soseki of abandoned temples, known as ‘temple stones’ (伽藍石, garan-ishi), became particularly prized for use in landscape gardens. Worked soseki can also occasionally be found amongst more recent and ‘high-end’ minka, where they are called ‘shoe stones’ (沓石, kutsu-ishi).

A foundation stone, presumably in a temple, with its ‘column seat' worked into a disc shape.

In order to lay the foundation stone, the first stage of foundation construction is no different for minka than it is for concrete foundations in modern buildings: the ground is excavated down to the depth of the bearing layer (jiban 地盤 or jiyama 地山), i.e. the level at which the soil is deemed hard enough or well-structured enough to support the weight of the building. This stage is known as ne-giri (根伐り) or ‘root cutting’. In minka, foundation construction in general is called chigyou (地形); isolated pad footings for individual posts are called tsubo-gata-gyou (壺型形) or ‘pot-form’ footings, and strip footings are known as nuno-chigyou (布地形) or ‘bolt-form’ (literally ‘cloth-form’) footings.

The foundation stone does not bear directly on the soil at the base of the excavation: a layer of large, split stones known as wariguri-ishi (割栗石) are first laid in the pit, oriented in a standing position, i.e. with their long axis vertical (koba-date, 小端建) so that their pointy ends penetrate into the bearing layer. These stones are then usually covered by a layer of sharp gravel. Again, this practice is strikingly similar to that followed in modern concrete foundation construction.

Various methods of founding stones on wariguri-ishi. Top: an isolated timber post on a foundation stone. Bottom left: a continuous timber groundsill on intermittent foundation stones. Bottom right: a continuous timber groundsill on a continuous dressed stone strip footing.

Compaction (chizuki 地搗き ‘earth pounding’ or touzuki 胴搗き ‘trunk pounding’) is achieved by the use of various implements: at the smaller scale ranging from a simple disc-shaped ‘mortar stone’ (usu-jou no ishi 臼状の石) with ropes tied around it, called a ‘turtle pounder’ (kame-no-ko-zuki 亀の子搗き), ‘flat turtle’ (hira-game平亀) or ‘flat octopus’ (平蛸 hira-dako); or a hard timber ‘trunk’ (tou 胴) with two or four wooden handles, for use by as many men, called variously an ‘octopus trunk pounder’ (tako-tou-tsuki 蛸胴搗き) ‘small octopus’ (ko-dako 子蛸 or ‘big octopus’ ou-dako 大蛸) On larger projects, a method known as yoitomake (ヨイトマケ) was employed: either ‘oar trunk pounding’ (yaguratou-tsuki 櫓胴搗き) or ‘pole trunk pounding’ (shinboutou-tsuki 真棒胴搗き), where a large timber trunk is suspended from a tripod or scaffold by means of pulleys and ropes.

An illustration of the various implements used for foundation compaction.

The shinboutou-tsuki method required the participation of the whole village: the villagers would raise the trunk by pulling on the ropes, then release the ropes in unison, dropping it into the hole. Naturally work songs and chants arose to aid the villagers in the co-ordination of their actions and to relieve the monotony of the work; these songs and chants show great variation across the different regions of the country.

Approximately 40 villagers engaged in ‘pole trunk pounding’ or shinboutou-tsuki of a stone foundation.

JAPANESE MINKA XI - FOUNDATIONS 1

As covered in earlier posts in this series, all ancient dwellings in Japan can be divided into one of two types: pit dwellings（竪穴住居, tateana juukyo), where a timber wall/roof structure was erected around an excavated pit which formed the below-ground floor of the dwelling; or the later raised-floor dwellings (高床住居, takayuka juukyo), with a timber floor structure elevated off the ground and supported between posts. In terms of their foundations, both of these types can (at least in their earliest forms) be categorised as ‘sunken post’ or ‘buried post’ (堀立て柱, horidate bashira) structures. As the name indicates, the timber structural posts (or inclined ridge-to-ground ‘rafters’) in these dwellings were set directly into the ground, usually to a depth of only 6-8 centimetres; their stability and that of the structure as a whole was obtained by connecting them above ground via a ridge beam, perimeter beams, purlins, and the like. The simplicity of this structural system allowed for the use of undressed, irregular, and crooked timbers, and didn’t require sophisticated tools or techniques. At the same time, these light, semi-permeable, and braced or triangulated structures demonstrated relatively good resistance against strong winds and snow loads.

An archaeological dig showing post-holes of horidate-bashira dwellings

The main disadvantage of this method is obvious: being in direct contact with the damp ground, the post bases were vulnerable to rot and insect attack, and soon decayed. Thus we see the appearance of foundation stones, either rough or dressed, placed half-buried in the ground, with posts set on top of them. At first, only ‘elite’ buildings like temples employed foundation stones, beginning in the Heian Period (794-1185); their adoption was extremely gradual, and horidate bashira survived in more humble minka and simple utility structures until the Edo Period (1603 - 1867) and even into the Meiji Period (1868 - 1912) in some regions. There were also many ‘transitional’ buildings that used a combination of posts on foundation stones and posts set directly into the ground.

Horidate-bashira on the left, posts on foundation stones on the right.

Diagram showing how a rotted-out horidate-bashira could be ‘upgraded’ to incorporate a foundation stone while retaining the healthy above-ground section of the post.

In the doma of the former Egawa Tarouzaemon residence, an early 17th century building perhaps better known for its wonderful lattice-like roof structure, there is an internal horidate bashira known as the iki-bashira or ‘living post,’ so called because it is said that the post was formed by simply cutting the upper trunk off a standing tree to the required height and dressing it in-situ, leaving the root system in place. Without excavation it is difficult to verify this story, but the earthen floor around the post displays a seemingly natural slope up to the ‘trunk’ of the post, hinting at the existence of a root structure beneath the surface.

The iki-bashira of the former Egawa Tarouzaemon residence in Izu Nirayama.

View of the doma and roof structure of the former Egawa Tarouzaemon residence, with iki-bashira at back right.

Another view of the iki-bashira and roof structure

Floor plan of the former Egawa Tarouzaemon residence indicating the position of the iki-bashira.

FLOOR TO WALL RATIOS

Builders and architects will often use a rough $/m² figure when arriving at a preliminary estimate of the cost of building a home, making reference to tables of figures published by quantity surveyors or found online.

A typical example of the kind of cost per area table of used in cost estimates. The ‘Low’ figures represent a no-frills, volume-built house with the cheapest finishes and fixtures, and the ‘High’ figures indicate a custom, architect-designed house with high-quality fixtures and finishes.

Something that is not factored into these estimates, however, is the effect of the shape of a house on its cost: in other words, the effect that the floor-area-to-wall-length ratio has on the quantity of various materials required to construct a house of any given floor area.

Take the following simplified examples, which consider only the house in plan view, and assume equal wall heights.

A house that is a 10m x 10m square in plan has a floor area of 100m²:

Likewise, a house that is a 20m x 5m rectangle in plan also has a floor area of 100m²:

But the total length of external wall in the former is 40m, and that in the latter is 50m, representing an increase of 25%. This means that the rectangular house shown above requires 25% more studs, plates and noggings, 25% more interior and exterior cladding, 25% more insulation, 25% more building wrap, and 25% more skirtings and cornices than the square house.

A courtyard house, with narrow internal corridors connecting the two main areas, decreases the ratio even further:

There is also the effect of articulation to consider, i.e. adding ‘ins and outs’ to the exterior wall:

At the other end of the spectrum, the absolute most efficient shape for a building if your only aim is to maximise the floor-to-wall ratio is the perfect circle, but this shape is impractical from both a construction and an interior layout/planning point of view:

So why would anyone build anything other than square? In fact, most modern volume-built homes are essentially square in plan, or at least fatter than they are skinny, with a central corridor serving rooms on either side. This allows developers to maximise the floor area of these homes on their relatively small lots while keeping the cost of constructing the envelope of the house relatively low.

A ‘fat’ plan typical of most volume-built houses.

But there are several advantages to opting for a narrow plan over a square one. Cross-ventilation and the penetration of natural light into rooms are both optimised, and there are more opportunities for northern (or, if you are in the northern hemisphere, southern) exposure; in the extreme scenario, every room can be given northern exposure, with a corridor running the full length of the southern side of the house.

Of course, on most projects the advantages of narrow plans listed above must be weighed against budgetary and site constraints and other considerations, but it doesn’t hurt to at least have floor-to-wall ratio in mind when determining the best plan-form for a house. Construction is a one-time cost, but the utility and amenity of a home are lifelong.

VERNACULAR PICTURES 16: OARS

Just some pictures of oars. Some good colour/pattern ideas in there for buildings!

JAPANESE MINKA X - TWO RIDGE MINKA

After covering several varieties of magari-ya in last week’s post, today I will look at another general minka type, the futamune-zukuri (二棟造り), or ‘two ridge’ minka. As the name suggests, these minka are basically two structurally independent buildings; they may be either entirely separate, requiring one to go outside when passing between them, or joined to some extent. They are most commonly found in the southern regions of Japan, from Okinawa to southern and central Kyushu. The two buildings of the whole are the hon-ya (本屋), the ‘main house’ with raised floor for living, sleeping, etc., and the earthen-floored oto-ya or ‘cookhouse’, (lit. ‘pot/cauldron house’ 釜屋); they are roughly the same size, and are arranged either with their ridges parallel (the formal name for this arrangement is 平行二棟式, heikou-futamune shiki ‘parallel two ridge type’) or at right angles to one another.

Example of a ie-nakae secchaku minka with the ridges of each building arranged at right angles to each other.

It’s not difficult to understand why this type of minka is found predominantly in southern Japan. In subtropical climates like Okinawa and southern Kyushu, separating the ‘cooking’ and ‘living/sleeping’ functions of a house into two separate buildings means that heat from the stove can be kept out of the main dwelling; another advantage of isolating the hon-ya from the oto-ya is that in the event that the oto-ya is destroyed by fire, the hon-ya will stand some chance of surviving (depending on the wind direction of course!). The scale of these dwellings tends to be quite modest; another advantage of the two-ridge type might have been that the two buildings can be completed in two stages, as funds become available. And of course, as with any vernacular building form, we shouldn’t overlook the cultural factors behind the evolution and persistence of any particular typology or design element, i.e. “that’s the way it’s always been done.”

The ie-nakae secchaku (イエ・ナカエ接着) is one name for a variant of the two ridge minka in which the two building volumes (here termed the ie and the nakae) touch (secchaku) at their eaves, and are joined below by walls to form a relatively unified interior space. The ie, or sometimes omote, are regional variant names for the hon-ya; the nakae is the oto-ya.

Map showing the distribution of various configurations of ie-nakae secchaku minka on the Satsuma Peninsular, southern Kyushu

Where the two roofs meet, a box gutter is provided. In our era when long lengths of sheet metal are cheap and readily available, box gutters are taken for granted; in pre-industrial times constructing a waterproof box gutter was a much more impressive technical feat, using only split bamboo, or perhaps a hollowed-out half-log.

Ie-nakae secchaku minka, showing the box gutter and infill wall where the two buildings meet. The box gutter is a combination of old and new: the (presumably original) technique of split bamboo cleverly lashed together into a kind of Spanish tile arrangement, with the upper convex ‘capping’ sections of bamboo directing water into the lower concave ‘gutter’ sections; and the modern addition of cheap and timesaving sheet metal to make the old bamboo waterproof rather than replace it.

JAPANESE MINKA IX - L-PLAN MINKA

Last week’s post presented a map showing the general distribution of different types of minka across Japan. Today I would like to look more closely at one of the types included in that map that I haven’t yet covered in previous posts on the subject: the magari-ya (曲り屋).

Magari-ya literally means ‘bent house’; in other words, a minka with an L-shaped floor plan. But what really characterises the magari-ya is its particular mode of occupation, of which the plan is merely the spatial outcome: the cohabitation of humans and animals (typically horses) under one roof. The main volume, the omoya or moya (母屋), is for humans; the ‘stable wing’, umaya or maya (馬屋), is for the animals, and the two volumes are arranged at right angles to one another, with each forming one leg of the ‘L’. The umaya usually extends out southwards from the south facade of the omoya, because this position enjoys the best access to sunlight: an indication of just how valuable horses were to the occupants of these houses.

Magari-ya are most commonly found in the Touhoku region of northern Honshu (the main island of Japan).

A map of the Touhoku region, showing modern prefectures by colour and principal cities.

Perhaps the magari-ya variant most synonymous with the form is the Nanbu magari-ya, found in the Touno district of central Iwate (the area was once the domain of the Nanbu clan, hence the name). Taking the former Fujiwara residence as representative, we see that the main entrance to the building is in the umaya volume, placed centrally and very practically at the inner corner where the two volumes meet, and leading directly into the niwa, the earthen-floored utility area. From this central position one can go right to the umaya (which has its own independent entrance, next to the main entrance), left to the daidoko (kitchen) at the rear/north, or around the corner to the partitioned, raised floor section of the omoya, which contains the ‘living’, ‘sleeping’ and formal areas of the home.

A grand example of a nanbu magari-ya, the former Fujiwara residence, Iwate Prefecture. The photo is taken from the west, showing the umaya wing to the rear right, and the omoya in the foreground. The two dark openings in the umaya volume are the main entrance to the niwa (left) and the umaya entrance (right).

Floor plan of the former Fujiwara residence, showing the stable wing (umaya) at the bottom (south).

Another variant of the magari-ya is the chuumon-zukuri 中門造り, which like the Nanbu magari-ya is closely associated with the Tohoku region, but this time on the western, Sea of Japan side. Characteristic of this variant is that the entry (with horse) to the dwelling is via a door in the gable end of the umaya, into the chuumon entry/passage adjacent to the stable, where the horse is left before proceeding through to the earthen-floored niwa in the main interior space of the omoya.

A thatch-walled chuumon-zukuri magari-ya, the former Yamada residence.

Floor plan of the former Yamada residence.

Chuumon-zukuri with a sculpted thatch umaya: the former Satou residence in Niigata Prefecture.

Floor plan of the former Satou residence

It’s striking how functionally similar the plan of the chuumon-zukuri is to that of the modern Australian garage-fronted house, where you enter in your car, ‘stable’ it in the garage, and then go on through into the house proper via a door between it and the garage. You don’t need to be an architectural historian from the future to point out that the size and position of garages in our homes says the same about the status and centrality of the car in our lives as the position of the umaya does about the importance of the horse to the occupants of the magari-ya.

JAPANESE MINKA VIII - DISTRIBUTION

Previous posts in this series presented the basic categorisation system for minka floor plan layouts put forward by Kawashima Chuuji. While this system is satisfactory in a general sense, and is useful in reconstructing the evolution of the minka from its earliest forms, Kawashima himself emphasises that such a neat taxonomy can never really capture the great diversity of minka seen throughout Japan, according to function, occupation, custom, climate, topography, socioeconomic status, and other variables. And what holds true of the country as a whole also holds true when it comes to attempting to identify distributions and patterns of minka by region, whether that be the regional distribution of any particular typology of minka, or the typology of any particular region. While it is understandable that the most typical or common minka type in any area will be held up as representative of that area, it should also be remembered that even within a particular region there will be many variations on the representative type, as well as other types, oddities and anomalous forms that resist classification. Thus it is impossible to create a really accurate fine-scale map of minka types according to region; such a map will be unavoidably low-resolution. Nevertheless, the exercise isn’t meaningless or futile, because the patterns are there, however messy they might be, and the alternative would be an analysis so granular and microscopic that any sense of them is lost. In any case, here is Kawashima’s own map:

Kawashima’s map showing the distribution of minka types across Japan (excluding Hokkaido)

The map’s legend enlarged

The legend reads:

• 広間型および広間的間取り　Hiroma-gata and ‘hiroma-like’ layouts

• ４間取り系間取り（田字型）Yon-madori kei madori (ta-ji-gata) four room layouts

• 曲り屋　Magari-ya literally ‘bent house’ i.e. L-shaped plans.

• 中門造り Chuumon-zukuri A sub-category of magari-ya.

• 妻入り（前土間、片側住居、本棟造り）Tsuma-iri (maedoma, katagawa juukyo, honmune zukuri) Gable-entry minka.

• 二棟造り（主屋無土間）Futamune zukuri (omoya mudoma) ‘Two ridge’ i.e. two building minka (without doma)

• イエ・ナカエ接着 (Ie-nakae secchaku) A form of two ridge minka where the two building volumes are joined to form a unified interior.

• 踏込み土間型 (Fumikomi doma-gata) ‘Step-in’ doma type minka

The hiroma-gata and yon-madori kei madori have been covered in previous posts. The other typologies shown on the map fit less neatly into Kawashima’s classification system; in the next few posts in this series I will look at them in more detail.

GREEN BUILDING PART TWO: IMPLICATIONS

This post will conclude the theme of the last few weeks - energy efficiency and its relationship to environmentalism - by examining the kind of ‘green’ building regulations discussed two weeks ago in light of the concepts introduced last week, and considering their implications on the possibility of ‘green’ building, and on the very concept of the home itself.

As noted last week in relation to automobiles, the Jevons paradox makes clear that any savings made through improved efficiencies, whether that be in energy, material, or space, will be eaten elsewhere; and this is no less true of building than of any other field. Say, for example, you make a more efficient hot water unit: where do the energy savings go? At the household level, the savings may be negated by the occupants, who introduce more energy-consuming devices into their home on the grounds that ‘we can afford it now’. If not, the energy they save will be taken up by others in the context of an increasing population; this is especially true of present-day Australia. Economically speaking, the money they save will either be spent, which is just transferring the consumption elsewhere, or perhaps deposited in an interest-bearing bank account, i.e. lent out by the bank to others, which furthers economic growth, which is also consumption.

Say you change your planning codes to allow, encourage, or mandate smaller, more space-efficient houses on smaller blocks. Is less agricultural land devoured? No: there are simply more people on more blocks on the same amount of land. Say you opt for ‘building upwards’ instead, and put everyone in apartment towers: does the required number of refrigerators, televisions, and washing machines decrease? No: it increases with the increasing number of households, even though each household is now living more ‘efficiently’.

Say you make a more efficient screen or monitor, so that each individual screen uses both less space and less energy (this is exactly what happened in the transition from bulky, power-hungry cathode ray tube screens to flat, energy-efficient plasma and LED screens); does the number of screens per household remain the same? No: instead of one or two screens per household in the 1980s, today there might be dozens.

The above examples reveal the problems and contradictions inherent in goals like ‘energy efficiency’ and ‘green consumption’. Consumption simply shifts to other people or other resources, and worms its way into ever smaller niches and cracks. But what are the implications of all this on the idea of home, in a metaphysical sense, particularly in light of concepts such as Ellul’s technique?

The idea of home is being assailed on two fronts: the regulatory and the material. It is difficult to find the right word to characterise this: the home has been pulverised, powderised, atomised, pinched, dismembered, quantified, disenchanted, bureacratised.

On the regulatory front, there might be no better example of the effect of technique than on that icon and image of the traditional home, the open fire. Once innocent, wholesome, poetic, mythic, a symbol of warmth and welcome, the hearth and heart of the home, the open fire has now been deemed by rational analysis to be, unacceptable, unsatisfactory, inefficient, environmentally unfriendly; its measure has been taken, it must be regulated out of existence.

On the material front, the totalising reach of technique can be seen in the change in timber products over the years. From building with whole logs, to large-section post-and-beam, to 2x4 stud wall framing with hardwood, to the same with softwood, to plywood, then OSB, then MDF, which is the literal powderisation of material: buildings made of sweepings and sawdust. MDF is less wasteful, more efficient, you might say. But none of these timber technologies have slowed deforestation in Australia or anywhere else, let alone reversed it.

The tendency of hyper-rational systems of technique to result in hyper-irrational outcomes is evident in the fact that today you can knock down a perfectly serviceable and sound 150m² brick home from the 1950s, a home that has paid its debt in material and energy terms many times over, and erect in its place a 500m² house with a three car garage, the whole suite of integrated ‘smart tech’ controls, solar panels and batteries, floor-to-ceiling triple-glazed argon-filled windows, and an air conditioner in every room, and as long as it achieves a six (now seven) star energy efficiency rating, it can officially be considered ‘green’. We might be aghast at the ‘waste’ involved in building the kind of primitive huts that were once common in Australia, with their large-section, old-growth hardwood timbers. In truth, the lifetime ‘footprint’ of such a structure would be vastly smaller than any passive or ten-star house. Yet you are not allowed to build and live in such a hut today, because the regulations don’t allow it.

In the 1970s you could obtain a building permit with a single sheet of drawings; today the volume and detail of the regulations and the resultant documentation required of architects and building designers is large and only increasing. The regulatory burden never shrinks but always moves towards growth and complexification, because regulatory bureaucracies (which, as you will recall, form a core part of the network of technique) will always act to increase and protect themselves, until, as Joseph Tainter points out, they eventually fall over. I don’t deny that the motivations behind building regulations are benign: the desire to make buildings safer, healthier, more amenable, less wasteful, is to be applauded. But at the same time the negative effects and deeper implications of this trajectory must also be acknowledged.

So if energy-efficiency regulations don’t in fact protect the environment but instead result in an increase in consumption, what is their point? Here is a challenging proposition: on the principal that ‘the purpose of a system is its outcome,’ this is the point, however unspoken, of such regulations. Not to ‘save the planet,’ but to allow us to continue to live in the manner to which we have become accustomed. The wind turbine and the solar panel are not avatars of environmentalism, they are avatars of consumption; efficiency regulations exist not to reduce consumption, but to make consumption more efficient, which is to say, to encourage it.

GREEN BUILDING PART ONE: CONCEPTS

This week’s post presents several important concepts that I believe should be understood by anybody interested in the subject of energy efficiency as it relates to environmentalism. It is intended to serve as a bridge between last week’s examination of one particular aspect of the recent changes to the National Construction code - an increase in the stringency in the energy efficiency provisions - and next week’s post, in which I will attempt to tie it all together by examining the implications of these concepts on the idea of ‘green’ buildings, and indeed on the deeper meaning of ‘house’ itself.

Technique

Jacques Ellul

In his book The Technological Society (1964), the French philosopher Jacques Ellul defines technique as “the totality of methods rationally arrived at and having absolute efficiency (for a given stage of development) in every field of human activity." As this definition makes clear, Ellul’s concept is not limited to technology in the material sense, but also encompasses process and procedure, methodology, bureaucracy, labour organisation, and so on. In Ellul’s view, technique is not a mere tool or function of people in society, but rather, in James Fowler’s explanation, “the defining force, the ultimate value, of a new social order in which efficiency was no longer an option but a necessity imposed on all human activity” by which “rationalistic proceduralism imposed an artificial value system of measuring and organizing everything quantitatively rather than qualitatively.”

The Jevons Paradox

William Stanley Jevons

The English economist and logician William Stanley Jevons was the first to describe what has become known as the Jevons paradox or the Jevons effect in his book The Coal Question (1865). The paradox is this: any increase in the efficiency with which a resource is consumed will result in an increase in the overall consumption of that resource. Jevons observed that the increase in the efficiency of steam engines - their ability to do more work with the same amount of coal, or use less coal for the same amount of work - resulted in an overall increase in the consumption of coal, not a decrease. This is because more efficient steam engines are cheaper to operate and thus become economically viable in a wider variety of applications: although the amount of coal required per steam engine to do a given amount of work goes down, the total number of steam engines, and the total consumption of coal, goes up.

The Jevons paradox is more of a counter-intuitive statement than a true paradox, but ‘paradox’ has proven to be a good term, as it gives a sense of just how resistant so many people are today to really internalising its meaning. Not because it is a particularly difficult concept to understand, but because it cuts to the heart of, and has uncomfortable implications for, the dream of ‘green’ or ‘environmentally friendly’ technology and the whole superstructure of technique that has grown up around it. The Jevons paradox gives the lie to the ideal of efficiency in the service of the environment, by pointing out that any energy or resources you save will just be used by someone else.

Perhaps rather than ‘counter-intuitive’ we should call the Jevons paradox ‘counter-ideological’, because the validity of entire green industry rests on the implicit assumption that the opposite is true: that an increase in the efficiency of consumption results in a decrease in overall consumption. To paraphrase Upton Sinclair: it is difficult to get a man to understand something when his worldview depends on his not understanding it.

Complexification

Joseph Tainter

In his book The Collapse of Complex Societies (1988), the American anthropologist and historian Joseph Tainter puts forward the thesis that technology plays a major role in the collapse of civilisations. Very simply put, the mechanism is this: problems are identified in society and novel technologies are developed to solve them; these technological solutions by their nature give rise to new problems, which in turn give rise to new technological solutions, and so on, with technology or technique piling on itself, increasing like the heads of the Hydra in a fractal-like multiplication and elaboration at ever-finer levels of complexity.

As an example of this phenomenon, Tainter has given the problem of vehicular CO2 emissions, which resulted in the mass-market hybrid car, where the solution was arrived at by providing cars with two power units instead of one, representing a huge increase in complexity. The solution itself was arguably a success, given that hybrids like the Toyota Prius can achieve fuel efficiencies of around 5 litres per 100km, impressive numbers when compared to a modern internal combustion-only car, but still only about the same as the Citroen 2cv, first produced in 1948.

But what about purely electric vehicles like the Tesla? you might ask. The increase in complexity in modern vehicles is not limited to the powertrain, of course: it is also driven by comfort, safety, the need for speed, reliability, and a whole host of other factors. I don’t mean to suggest that these things are bad, or in any way not genuine improvements, just that we should also accept that they come with costs. Electronification in particular has vastly increased the complexity of cars, and has been made possible by the invention of the transistor, then the integrated circuit, then increases in the processing power of silicon chips and the efficiency of their manufacture.

Weight is a good proxy for complexity in cars: the 2cv weighs in at around 585kg; a Prius is more than double that at around 1200kg. Teslas weigh anywhere from around 1700kg to 2400kg, and a single Tesla battery alone doesn’t weigh that much less than an entire 2cv. These weights are representative not only of energy consumption per unit distance, whether than be petrol or electricity, but also of the sheer amount of material and energy embodied in the manufacture of the vehicle itself.

Here we see the Jevons paradox at work, both at the resource level and at the product level: despite increases in chip efficiency, world silicon production has increased from around 4 million tonnes annually in 1990 to around 9 million today; cars per unit are ever-more efficient in their fuel consumption, but the total number of cars produced goes ever upwards.

Fungibility and Liebig’s Law

Carl Sprengel

In discussions of resource availability and depletion, it is often assumed that resources are fungible: that is, when any particular resource becomes unavailable or too expensive through scarcity, it can simply be swapped out for another without significant effects. This assumption is especially common in regard to energy, the ‘master’ resource upon which the extraction and utilisation of all other resources depend. As the thinking goes, coal replaced wood as the primary energy source at the beginning of the industrial revolution, then oil and gas overtook coal, and now ‘renewable’ energy sources such as solar, hydro, and wind are poised to replace fossil fuels. This leads us to Liebig’s law, or the law of the minimum, developed by the German botanist Carl Sprengel in 1840. Liebig’s law states that the growth or health of any system is limited not by the total resources available, but by the availability of the least available resource. To illustrate this concept, let’s take an example from agriculture, the field where Liebig’s law was first formulated: it doesn’t matter if you have perfect rainfall, sunlight and heat, and your soil is perfectly balanced in all other essential minerals; if the soil is deficient in nitrogen, then it is the level of nitrogen that will determine the ultimate health and yield of your wheat crop.

A joule from a wind turbine may be fungible with a joule from a coal-fired power plant, but this doesn’t mean that the energy sources themselves are equivalent in other ways. Fossil fuels are taken so for granted that it’s easy to forget what a miracle they are in terms of their energy density, storability, and ‘readiness’. Coal in particular can be literally dug out of the ground and burnt to obtain energy without processing or any other intermediate steps. Wind turbines must be built (of large amounts of concrete, steel, fibreglass, and rare elements), transported, erected, and maintained, and all of these stages require their own energy inputs; they have a limited lifespan and eventually fail; and they are ultimately harvesting a low-density source of energy: wind (which is really a form of solar energy). The same things are true of photovoltaic solar. People will often counter these objections by an appeal to technological omnipotence: claiming that when rare-earth elements become scarce, we will go to space and mine them from asteroids; or that wind turbines will eventually be made by and with self-replicating bacteria; or some other iteration of “they (scientists) will think of something.” But these fantasies are based on nothing more than a kind of quasi-religious faith in technology and progress.

The Citroen 2CV

THE NATIONAL CONSTRUCTION CODE 2022

I would like to take a bit of a detour today, away from the recent focus on Chinese vernacular architecture and into some ‘talking shop’. This is prompted by the recent adoption (on May 1st 2023) of the new National Construction Code, which replaces the previous NCC released in 2019.

For those unfamiliar with the NCC, the Victorian Building Authority website provides this explanation:

“The National Construction Code (NCC) sets out the requirements for the design and construction of buildings in Australia, including plumbing and drainage work. It sets the minimum required level for the safety, health, amenity, accessibility and sustainability of certain buildings.”

The NCC has previously been comprised of three volumes:

Volume One, The Building Code of Australia Volume One, which covers mainly Class 2-9 structures;

Volume Two: The Building Code of Australia Volume Two, which covers Class 1 and 10 structures; and

Volume Three: The Plumbing Code of Australia.

The 2022 NCC retains this basic three-volume structure, but also introduces significant changes and additions to the organisation and content of the Code.

The deemed-to-satisfy solutions for Class 1 (basically houses) and Class 10 (garages, carports and the like) structures, which used to be contained in Volume Two, have been split off into a new document, the ABCB (Australian Building Codes Board) Housing Provisions Standard 2022; Volume Two now contains only the performance solutions for Class 1 and 10 structures.

There is a whole new Section to the Code, “Liveable housing design,” which is presented in both Volume One (as Part G7) and Volume Two (as Part H8), and also in its own dedicated Standard referenced in these Parts: the Australian Building Codes Board Liveable Housing Design Standard 2022. This Standard contains new requirements (to come into effect in Victoria on October 1st 2023, after a five-month transitionary period where adoption is optional) intended to ensure that new dwellings “better meet the needs of the community, including older people and people with mobility limitations.” It is an adaptation of the ‘Silver’ level requirements of the Liveable Housing Design Guidelines (LHDG) 2017, but essentially makes mandatory in private dwellings certain design elements that until now had been optional: things like step-free access to dwelling entrances, minimum clear widths for openings and corridors, accessible bathrooms, and the like. Previously such measures were generally only required in public buildings, with the specifics given in Australian Standard 1428 - Design for access and mobility.

The other major change to the Code is an increase in the stringency of water use, energy efficiency (to the tune of around 30%) and condensation mitigation requirements. The new energy efficiency requirements are contained within Volumes One (Section J) and Two (Part H6), and also in the Standards referenced therein: the ACAB NatHERS (Nationwide House Energy Rating Scheme) Heating and Cooling Load Limits Standard 2022, and the new ACAB Whole-of-Home Efficiency Standard 2022. The NatHERS scheme is used to provide a streamlined pathway to achieving the energy efficiency standards required by the NCC, and it assigns a star rating to new dwellings; the minimum rating required, previously six stars, is now seven. Likewise, although NatHERS has contained heating and cooling load limit provisions since 2019, those required by the 2022 edition are stricter.

The new Whole-of-Home Efficiency Standard, as explained in its introduction, “provides a holistic assessment of the energy performance of a dwelling, covering both thermal performance and domestic services. To meet the WOH requirements, the net equivalent energy usage of a dwelling must not exceed a certain allowance.” This is in contrast to the approach adopted by the NCC and NatHERS until now, which has been more focused on managing “heat transfer through the building envelope to separately minimise heating and cooling loads.”

All this represents significant complexification and growth of the Code over the previous edition, and is indicative of a larger general phenomenon. Next week, I would like to explore its implications from a more abstract and holistic perspective, and consider what it means to be ‘green’.

CHINESE VERNACULAR DWELLINGS IV

As mentioned in last week’s post, timber construction doesn’t easily lend itself to building at extremely large scales or in multiple storeys, and traditional Chinese architecture is no exception here: there are relatively few examples of large timber structures in the historical record. Timber architecture does however encourage a degree of systematisation or ‘modularity,’ if those terms can be applied to pre-industrial structures, and this has been the case with the ‘hall’ (tángwū 堂屋), whose gradual standardisation has meant that it displays little variation over time and region. These factors go some way to explaining the agglomerative character of Chinese architecture: increases in scale and complexity are achieved not by the erection of grander and more complex unified structures, but by the addition or duplication of relatively modest and simple groups or ‘units’ of tángwū and their associated courts (院子 yuànzi).

The tángwū and yuànzi present a beautiful contrast. Against the simple, rectangular and relatively unchanging form of the tángwū, we see in the yuànzi an infinite variety of sizes, forms, functions, and atmospheres. It is tempting to interpret the two in almost yin-yang terms: the tángwū is rigid, stable, material; the yuànzi is spatial, fluid, yielding, freely receptive and responsive, with the capacity to accomodate the creative energy which finds no outlet in the tángwū. Indeed, when we speak of Chinese architecture increasing in scale and complexity in response to emergent societal conditions and requirements, it is in the yuànzi, not the tángwū, which this response is expressed, and to the Chinese people it is the yuànzi, not the tángwū, that is in every way the heart of the architectural ensemble.

CHINESE VERNACULAR DWELLINGS III

Last week’s post examined at the nature and evolution of one of China’s most characteristic vernacular dwelling plan-forms, the sìhéyuàn (四合院), via the book Exploring Space in Chinese Residential Architecture. Here I would like to take an introductory look at one of the two fundamental elements of these dwellings: the basic building unit or ‘hall’ 堂屋 tángwū (the other being the courtyard 院子 yuànzi). It could be said that the essential nature and form of Chinese architecture is distilled in these two elements and their relationships, and they are found everywhere, across eras and regions, from the grandest temples and villas to the most humble dwellings.

At the heart and beginning of Chinese architecture is the concept of protection. From the earliest recorded history, the Chinese have sought to defend their living environments from threats of invasion by foreign enemies, winter winds, and sand storms by erecting walls to enclose them. From the neolithic period, clusters of dwellings have displayed a centripetal character, and from the Xia Dynasty (c. 2070 - c. 1600 BC) we already see the pattern of tángwū being situated at the north, south, east and west of a central inner courtyard. This form, the sìhéyuàn, reached its maturity in the Han Dynasty (202 BC - 220 AD), and has continued down until the present.

The age-old Chinese practice of erecting thick, sturdy earthen walls around dwellings, villages, and cities, not only to fortify them against the ‘outer’ but to clearly demarcate the ‘castle’ and consolidate the sense of the ‘inner,’ has given rise to the development of a unique, hermetic world within these walls and cloisters, with the oppositional relationship between the tángwū and yuànzi at its core.

As historical sources indicate, the structural basis of Chinese architecture has always been the axial timber frame, and the tángwū is no different. Such a structural system is not really capable of producing large, complex buildings, and the simple, pure plan-form of the tángwū is an expression of this orderly, ‘modular’ structural system, rather than being expressive of any particular function. Though the use and scale of tángwū may vary, they all share the same basic essential characteristics: the orderly arrangement of columns, typically a single span in depth but sometimes more, an odd number of bays, an open ‘front’, and a closed ‘back’.

Elevations showing a range of tángwū, from the simplest three-bay pattern all the way up to nine and eleven bay examples.

The building of a tángwū involves first constructing a raised platform or podium, typically of compacted earth or rubble faced with stone, then erecting on it the building itself, with its entry and all openings in the long southern facade facing a courtyard or open area, blind rear and gable-end walls, and a hipped or gabled roof.

Cutaway perspective of a tángwū, showing the central táng ‘living’ area and wòshì ‘bedrooms’ to either side of it.

The fact that tángwū always have an odd number of bays is thought to have arisen both from the influence of yin-yang philosophical concepts, and also from the desire to grant the ‘chief’ or head of the household a physical position within the tángwū that gave full dignity and expression to the functional centrality of his role. The central bay of the tángwū occupied by the head is called the 堂 táng. The odd number of bays, with an equal number of bays (typically bedrooms, 臥室 wòshì) on either side of the central táng, the central entry steps leading to the táng, and the role of the táng as the ‘gatekeeper’ space which must be passed through to access the other areas of the building, all emphasise the centrality of the táng and the importance of the axis that runs through its centre, and give the tángwū as a whole a strong sense of overall symmetry.

Diagram illustrating the highly symmetrical form of the tángwū and the importance of the central axis.