Mortice & Tenon 56 Summer 2014

NUMBER 56  SUMMER 2014

Framing in Australia Chris Nance A European Standard? David Yeomans Japanese Timber Fences Dimitri Malko A Geometrical Design Workshop: Laurie Smith, Rick Collins, Nicole Collins

At Work, Buckler’s Hard

Henry Russell and friends at work building a new timber framed replica of an 18th century workshop that will become the Shipwright’s School at Buckler’s Hard.

Follow their progress at: www.bucklershard.co.uk

Picture call… Show us what you do and how you do it editor@carpentersfellowship.co.uk

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The Carpenters‘ Fellowship Advancing the practice and study of timber frame carpentry

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CONTENTS 2

At Wo rk Buck ler ’s Hard

4 I n Site D avid Le viatin 7 Framing in Australia Chris Nance

12 A Euro pean Standard?

D avid Yeomans

1 6 Japanese Timber Fences D imitri Malko

2 5 A G eo metrical Design Wo rksho p

Laurie Smith, R ick Collins, Nicole Co l l i n s

3 5 R aisings Tree House Nozomi Nakabayas h i

Copyright Copyright of the Mortice and Tenon is held by The Carpenters’ Fellowship.

Copyright of individual articles, illustrations or photographs remains with the authors, illustrators or photographers.

Printed by Welshpool Printing Group Severn Farm Enterprise Park Welshpool, Powys SY21 7DF on C o c o o n recycled paper ISSN 1 1368 4612

Editor David Leviatin Sub-editing SOServices Design Mark Clay

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In Site The Poetry of Joinery Often, when I go out looking for one thing I come across something else; something even better than what I went out looking for.

Recently, while walking around the dusty streets of the Laotian town of Luang Prabang at dawn looking for saffron clad monks, I came across a temple, inside the courtyard of which I found the dismantled remains of an old timber frame building.

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There was a note affixed to the pile of timber, written in Lao, that I was told when translated into English meant something along the lines of: Use this timber as you like.

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Fra ming i n Au st ra l i a In late autumn 2013 I was approached by a couple in the New England region of New South Wales, Australia.

They were planning to build a new home for their young family and the scope was simple – they had a large farm with a fair part covered in native forest and they wanted to build a modern house from the materials on site.

Sure, I said, no worries.

The property was a long way from town and about 600 km from my home, so I figured the best option was for me and my ‘willing’ helpers to set up camp on site. I found that most of the place names in this area have Celtic origins and it seems that so too do the weather patterns. As winter loomed we prepared our accommodation as best we could and got stuck into the work at hand, despite the cold.

The Trees The most dominant feature of most Australian forests is the Eucalypt, with over 850 species growing in vastly differing conditions and climates across the country.

Eucalypt timbers can range from the likes of the

‘Ironbarks’ which are among the hardest and strongest timbers in the world through to some of the ‘Ash’ type Eucalypts which are relatively soft with low durability, and there are many types between.

On this project, the dominant trees included Red stringybark (Eucalyptus macrorhyncha), Messmate stringybark (Eucalyptus oblique) and also Manna Gum (Eucalyptus viminalis) with the latter not being a great timber for framing due to its relatively low strength and durability. The Red stringy is a great timber, considered moderately durable with a very low shrinkage rate and a nice straight grain that splits and works well. The timber of the Messmate stringy is somewhat similar in appearance but has a much higher shrinkage rate and a lower durability, making it our second choice on this frame, which was despite the fact that the Messmate trees are much larger and carry a lot more timber than the Reds.

All images: ©Chris Nance 2014

Chris Nance

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Forest Work Having designed the frame and compiled our cutting list, we set off into the forest to select the trees we needed. Some of the areas on this farm had very difficult access so we decided to fell and mill in the forest, which reduced our needs to move logs. When selecting the trees, great care needed to be taken to ensure that the trees not only met the needs of the frame but also looked after the forest.

A very common feature of trees in Australia is the presence of a termite pipe running through the heart of the tree. Often seemingly healthy trees can have a considerable hollow and can be unsuitable for a lot of uses. In general the younger trees tend to have less pipe and we found that the Messmate was much less prone to piping than the Red stringy. With that in mind, we took great care and the timber cutting on this frame worked out really well, with very few selected logs proving unsuitable for the frame.

All images: ©Chris Nance

Barking Mad The most distinctive feature of the stringy Bark trees is the thick and fibrous bark for which they’re named.

This bark is not the chainsaw’s best friend so we found it best to de-bark the base of the tree where the felling cuts were to be made prior to felling and then de-bark the remainder of the logs prior to milling. If done immediately after felling, the bark is quite easy

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to remove with an axe and crow bar as the moisture content is still quite high, but if it is left too long the barking can become quite an arduous job. A few blows along the length of the log with the back of the axe breaks the seal and then the bark can be peeled off in large sheets with a small bar.

Stringybark has been a very common building material in Australia for probably thousands of years.

The Aboriginal people used it (procuring it in much the same way I’ve described) to build shelters, canoes and numerous other items. Europeans, when they arrived, borrowed these techniques and began using the bark for a huge range of early settler dwellings. It was the Australian equivalent of thatching and, as white men began clearing the forests for farming, entire pioneer villages were often clad with sheets of this bark. It is not a great long term cladding though because fire, termites, sun and rain have destroyed many of these early buildings but it was an important building material for early European settlers.

Timber Milling The milling setup I have is a chainsaw rail mill which worked really well on this project due to its light weight and portability. I use a Stihl 880 chainsaw which has a sliding carriage bolted to the bar and the carriage runs on a rail secured to the log. The process involved for milling a boxed heart beam, for example, involves fixing

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All images: ©Chris Nance 2014

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the rail to the log (nice and straight), taking a flitch off each side and then removing the rail and rolling the log to repeat the process on the other faces. It generally produces very accurate beams and, as long as the chain is regularly sharpened, the finish of the timber is quite fine.

I find this mill setup great for doing this sort of milling.

It’s not an ideal way to mill small section timbers but for large section size milling it works really well, and is a considerably cheaper setup than some of the other milling rigs. I also use this to mill my curved slabs, by fixing the rail to another log or to a purpose built rail which I have made up.

The Frame There was about 16m³ of mostly 200 x 200mm timber required for the frame, and the milling took us about four weeks.

The overall house design was to be quite modern, with a low profile roof and direct glazing to the entire northern side (remembering it’s in the southern hemisphere). So the frame design was kept fairly simple, but as the clients wanted a few natural features retained, a keen eye was kept for any interesting shaped logs.

As we were milling the Red stringybark, curved limbs were kept and slabbed up for braces. The remarkably low shrinkage rate of the Red stringybark timbers meant they were quite suitable for braces and it meant we were able to get some really nice shapes. The construction of the frame was all fairly normal with it broken down into four wall-frames and six cross-frames. We were on a tight budget so I had to simplify the frame in a few places as we progressed and I redesigned the cross frame joinery so that I only had to lay up the two end cross frames, with the intermediate frames largely distance scribed. We also decided to buy in softwood common rafters so that simplified it a bit too.

I managed to sneak in a couple of jowls on the front wall frame and I kept the natural wane of the log on the inward face, which I think came up quite nice.

During the framing I found both the Red and Messmate stringybark timber to be nice to work with and somewhat similar to oak in a workability sense. All of the pegs used had been previously made and these were mostly Blackbutt (Eucalyptus Pilularis) and Spotted Gum (Corymbia Maculata) which are both good and strong timbers. I found the Red stringy to make nice pegs too, due to the straight grain, but I don’t feel they are as strong as the other timbers I use.

The framing took us about 8-10 weeks and we assembled it with a forklift on the concrete slab in two and a half days. The topping out ceremony was an enjoyable event with the plan being devised for one peg to be left out and after all was finished the client had to find the missing peg, drive it and cut it off, all the while we had the stopwatch counting the number of beers they had to buy us! Quite a party!

Building Completion Once the frame was up, we stayed on to finish the rest of the build. The common rafters were cut in, the metal roofing put on, the double glazing installed and then the rest of the work tidied up over the ensuing months.

Having started felling trees in June 2013, I was really pleased with the end results and very glad to be finished in early February after eight months away from home.

Chris Nance learned timber framing with Alan Ritchie in Wales after receiving a Worldskills scholarship in 2006. He has since started his own business and built a number of timber frames across Australia.

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A Europ ea n S t a n d a rd?

David Yeomans Many of us are involved in the assessment and repair of historic timber structures and the first stage of any repair programme is to assess the condition and structural capacity of the existing structure. This may be particularly problematic if there are to be changes to the structure as it now stands, even if that only involves putting on a new roof covering. Just as with anything concerning building structures there are moves towards the development of standards. The International Standards Organization has had a standard for the assessment of existing structures for some time and when the standard was revised recently I was part of a committee that added an annex to deal with historic, or heritage structures, something that had been excluded from the original document because of the special problems they pose (ISO 13822, Bases for design of structures – Assessment of existing structures, Annex I, Heritage structures). Now there is a move to develop a European standard specifically for historic timber structures.

We might well ask whether this is necessary as assessing timber structures is a skill that many of us have developed. It is a skill that I addressed in part in my article ‘The engineer as detective’ (M&T, Spring 2007) and it is the kind of skill that we develop through the experience of looking at many structures. A reasonable question is whether such skills can be encapsulated in a code of practice because the very existence of a code suggests that it may well be read and used by others who have not developed the skill and this must make the drafting of the code a difficult task. Perhaps it would be better not to have a code to avoid the dangers of the inexperienced thinking that it provides them with all the guidance that they need.

That is clearly a danger, and one to be navigated in drafting the document, which must clearly identify the necessary steps to be taken, but the principal advantage of having a code is that it can address the task of assessing the strength of individual timbers. If a clear methodology for that aspect of the work can be devised then that will not only be useful to those surveying the structure and assessing its overall strength, it will also provide clear rules that can be applied by building control officers.

The problems that we may be faced with are:

How to assess the capacity of an historic timber that does not reach the necessary grade to carry the design load. We must all have seen timbers that should have failed, according to the code, but which are performing perfectly well.

How to assess the capacity of timber that has suffered either fungal or insect attack that has clearly weakened it.

What is the capacity of the remaining section?

Providing means for assessing the strengths of individual members is clearly a valuable service that a standard could provide and if this is the outcome then it is to be welcomed. Unfortunately problems arise with the one standard that already exists.

It’s worth being clear about what we are trying to do when we assess an historic timber building. The purpose is to determine the ability of the structure to carry the intended loads and to indicate where it might be necessary to carry out repairs or strengthening. That is true for any historic structure and, while timber does not weaken with age, it is subject to biological attack and may well require some intervention to remedy such damage or to deal with other changes that have occurred during the building’s life. As historic timber structures have a cultural value, which is to be preserved, any proposed changes must respect the historic character of both the structure and the materials that it supports. It follows that work often needs be undertaken in consultation with conservation specialists. Moreover one is trying to keep any interventions to an absolute minimum, and any standard needs to have that as a goal.

Of course a European standard needs to be applicable in all the countries of the EC, but building standards present a particular problem because of the parochial nature of building industries. The half-timbered tradition

Left: Different periods and styles of timber framing above shops in Rouen. Despite superficial similarities to other national styles such as this Fachwerk in Franconia, right; approaches to repair and conservation differ widely from country to country.

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Floor using chestnut beams in Santiago de Compostela

of England has its parallels in the colombage of France and the Fachwerk of Germany but there is, to the best of my knowledge, no equivalent in Italy. I have seen buildings in Spain that suggest the possibility of timber frames concealed behind a façade of plaster but have no detailed knowledge of that. The timber reinforced masonry of Italy to provide earthquake resistance is quite different from the timber frameworks of Lisbon, built after the 1755 earthquake there, which is more like a timber frame infilled with masonry. And all of that is different from what I call Ottoman construction comprising light timber first floor stud frames on a masonry ground floor seen in Greece, Turkey and, of

course, Cyprus. In northern and eastern Europe there are log buildings. Moreover all of these different traditions have their regional variations.

Apart from the typological differences in timber structures across Europe, there are also differences in climate and different pests that will attack the timber. The Mediterranean countries have a quite different climate from the wetter north. Perhaps fungal attack is less of a problem, but they have termites.

Ideally the drafting committee should have members from countries representing all these different timber building traditions, but as with many such working groups only a dedicated few attend meetings and are

A nineteenth century house in Normandy with ‘traditional’ framing

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A roof truss heel joint of typical Italian construction

actively woking on the project. The team is chaired by Nicola Macchioni, a wood scientist. There is another Italian wood scientist, Luca Uzielli, and to balance these two are two engineers, myself and Eleftheria Tsakanika, who has been involved with timber design and restoration in the Athens region. Three of us were involved with an earlier working group that produced a working document, which is the basis for our present deliberations (Helena Cruz et. al., Guidelines for the On-Site Assessment of Historic Timber Structures, International Journal of Architectural Heritage, http:// dx.doi.org/10.1080/15583058.2013.774070) Perhaps it would be simpler if we were starting with a blank sheet but there are existing European standards or rather there is a European country that has such standards. Italy’s UNI 11138 provides guidelines for the preliminary evaluation and repair of historic timber structures while UNI 11119 deals with their more detailed diagnosis. (Nicola Macchioni was on the latter’s drafting committee.) The existence of such standards is hardly surprising because, although Italy is not renowned as a country with a tradition of timber buildings, it does have a large number of historic buildings. Thus, an early proposal was that it would be possible to model the European standard on UNI 11119. However a problem was that the standard had been written by timber scientists and so did not have an engineer’s approach. Notably it included the requirement that every timber in the structure should be stress graded.

I objected to that on the grounds that if I proposed to a client that I

would grade every timber I would be fired and he would look for someone who could do a cheaper job. Clearly an initial assessment of the structure should consider the kinds of forces in the members and perhaps some preliminary assessment of the stresses. In that way the detailed stress grading could be limited to those timbers under the higher stresses.

Fortunately that view prevailed and the recommendations that we made in the preliminary document had a much greater engineering bias. In fact the approach is now that engineering issues should take the lead in any assessment. That means that there should be a preliminary assessment of a structure to determine the load path, i.e. the means by which the loads are brought to the ground with the intention being to identify those timbers that need to be stress graded. Clearly for the kinds of frames we are familiar with lightly loaded braces and many members that are in simple compression will have low stresses and hardly need the same attention as members in severe bending.

Our present task is to develop the draft document that we have into a useable code, which means addressing ourselves to the likely knowledge level of those who may turn to such a document for guidance. We have to be careful not to take for granted aspects of timber structures that might be basic knowledge for us but which would not necessarily be familiar to the majority of engineers. But perhaps the most difficult task is the technical one of devising methods for grading to replace the grading methods that have been developed for modern commercial timbers but which are ill suited to historic timbers and their working conditions.

David Yeomans is an engineer and historian specialising in timber frame structures.

The roof of a Palladian Villa in the Veneto (restored)

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Photo 1: A sculpted wooden palisade in Yamagata prefecture that features a high stone foundation

Images: ©Dimitri Malko 2014

Photo 2: Corner detail showing fretworked elements and engraved gable boards

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J a pa nes e Ti m b er Fe n ce s Dimitri Malko

Palisades in Traditional Buildings Japanese buildings are famous for their fine execution and the elegance of their forms. The types of architecture imported through the centuries from Korea and China and in the beginning only reserved for religious sites, have become general and are now also applied to residential buildings: the result is a magnificent style of which a few examples are shown in photos 1 to 5.

Photo 3: A palisade in Yamagata prefecture surrounding several kura, store houses that were used for the collection and storage of the region’s taxes in the Edo period (18th and 19th centuries).

Also, the palisade is pitched high on a stone wall above the moat and has regularly placed arrow-slits. The lower part is cladded with boards, the upper part is coated with earth.

Photo 4: Example of a traditional Japanese ry common in Japan

Images: ©Dimitri Malko 2014

In Japan, the temple carpenters or mia-daikku are considered the aristocrats of carpentry. They have managed to keep alive centuries of received craft knowledge by continuing to practice ancestral methods of workmanship. I had the chance of spending two years in Japan, and working for a mia-daikku master, Katôsan. While Katô-san’s company does work with temples, it also builds and repairs many other types of traditional timber structures such as fences and palisades.

The development of Japanese architecture was influenced by many different factors. First, Japan’s geographical position – neighbouring a very powerful and prosperous empire, China - is an important and influential factor to consider. Second, the humid and temperate climate due to the streams of the Pacific Ocean and the ever present risk of seismic activity played their roles in determining the nature of building construction and the character of carpentry. Finally, a very long period of two centuries of isolation, due to the political structure of the shoguns, help explain Japan’s unique forms of architecture and the carpentry methods developed over time to realise them.

The forces and the ideas that have shaped the overall look and practice of Japanese forms of architecture and the methods of building construction developed to realise these forms can be seen in all sorts of structures, both grand and humble. So it is no surprise to see the unique Japanese stamp when looking at the seemingly simple and utilitarian lines of palisades, walls and barriers that one encounters when travelling throughout the country.

Traditionally the Japanese do not have fences surrounding their houses and gardens as we do in Europe; their properties are enclosed by elaborate palisades and high barriers often capped with fully clad roofs.

Below is an illustrated discussion of a few of the different types and styles of boundary wall (and typical materials) that can be seen throughout Honshû, Japan’s main island.

Photo 5: Old wooden palisade of the Edo era (city of Miki – 19th century)

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Drawing 1: Yamato-bari

Photo 6: An exerior view of a chestnut wood and cedar palisade at the house of Mori-sensei. Ishinomaki, Miyagi Prefecture

Drawing 2: Me-ita-bari

Images: ©Dimitri Malko 2014

These traditional palisades are covered with many different materials including: copper, clay tiles; multiple layers of cypress bark and also in wood. Drawings 1 and 2 give two examples of roof cladding using wooden boards. The first of which, the yamato-bari, is meant to reflect the shape of a mountain or yama; the second, me-ita-bari, makes use of covered joints.

Sukiya Kenchiku – Tea culture architecture The 16th century (the Momoyama period, 15681614) saw the development of tea culture in Japan.

Demand grew for utensils used for the tea service. At the same time the need arose for new form and style of architecture that would harmonise with the ideas conveyed by this new cultural phenomenon. The outcome was a new style of design, the sukiya kenchiku (literally: ‘tea-culture architecture’), with refined lines and a rustic style where diverse materials were used. The keen interest of Japanese high society in this new simple and rustic architecture is explained as a response to the decorative excess of samurai and ruling class dwellings which was the fashion during this era.

The Edo period (1615-1867) saw the Japanese borders closed for two centuries, during which time Japanese architecture developed unaffected by influences from the outside world. The sukiya kenchiku architectural style became widespread and became characterised by very elaborate building forms that were influenced by the humid climate as well as unpredictable seismic activity. In the building of tea-houses, called chashitsu, many different materials – bamboo, liana vine, cedar, cedar bark and chestnut wood – are used to create the most simple and rustic building possible, which is in harmony with the sumptuous gardens surrounding it.

Around these teahouses palisades are used to define and demarcate a world of calm and serenity.

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Photo 7: View from the garden

Photo 8: Details showing an oblique return angle in the palisade.

Chestnut wood is used for the braces that support the palisades and in some parts for the vertical cladding. All the structural parts are made with Japanese cedar.

Following are three examples of contempory Sukiya Kenchiku-influenced work executed by Katô-san’s company. a) Chashitsu no he (tea-house palisade) Photos 6-9 Here is an example of a he (palisade) for a teahouse situated in the city of Ishinomaki, prefecture of Miyagi, built for a doctor, Mori sensei. The exterior side is

composed of two parts: the lower part is clad with wooden cedar planks with joint-covers; and the high part is coated with earth. The interior face is clad with cedar bark, secured with chestnut battens (half hexagonal mouldings) and fixed with traditional black smith’s hand-made nails. The roofing is composed of clay and copper tiles (drawings 3 and 4). b) Kuri lokkake no he – the hexagonal chestnut wooden palisade (photos 10-12) This is a second type of palisade we can see around sukiya kenchiku buildings: comprising chestnut

Drawing 3: Detail of the brace, called hikae-bashira. The brace, hewed in the shape of a hexagon, is tied to the structural posts by an ingenious Japanese assemblage called a nuki, and fixed with hard wood pegs.

Photo 10: Ensemble view of a kuri-lokkake no he being built

Drawing 4: Elevation and cross-section of the palisade Photo 11: Detail of the palisade

Images: ©Dimitri Malko 2014

Photo 12: The reverse side of the palisade is lined using cedar bark sheets secured with chestnut battens.

Photo 9: A mon or gate. These palisades are magnificent examples of carpentry work with refined lines that seem to dissolve into the garden situated behind.

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Photo 15: The removeable sections in place, set in the main palisade.

Images: ©Dimitri Malko 2014

Photo 13: A removeable section of a Yaki ita no he palisade (front view): the facing is composed of burnt and brushed cedar boards.

Photo 14: The reverse of the same palisade section: the structure of the palisade is composed of two posts supporting horizontal elements (“nuki”) onto which the boards are nailed. The whole structure is braced with two “hikae-bashira” (brace posts).

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hexagonal vertical battens hewed with an adze and assembled together very tight to one another in a cedar structure, the kuri no lokkake no he presents a very interesting and rough face. c) Yaki ita no he – palisades with burnt board cladding (photos 13-15) A third example of a sukiya kenchiku palisade: the yaki ita no he. This palisade was erected around a private parking, which explains the fact that the burned boards were set on the inside face.

In this case, the whole fence is built with one type of timber; sugi or Japanese cedar. On the structure are nailed cedar boards that are tangentially sawn and were previously burnt on the surface, then brushed.

Photographs 13 and 14 show the construction system that is applied to each of the palisade’s modules. d) Take no he - bamboo palisade: Photo 16 illustrates an example of a traditional sukiya palisade in Nara, composed entirely of bamboo that has been unrolled and dried. The resulting bamboo sheets are then nailed on a cedar super-structure (seen by the posts protruding above the top of the palisade). The roofing is composed of clay half circular tiles.

These palisades enclose magnificent gardens, very precise in their conception and realisation. From the gate (the mon) begins a winding beaten path that leads to the tea house, a path which meanders only to certain elements of the garden, unlike the vast open spaces created in European gardens.

Gaki – Low fences Often the paths in gardens are lined with low fences or barriers, called gaki. Generally made of bamboo bound with liana rope, integrating themselves in the landscape, they create a clear delineation between the garden and path. They guide the footsteps of the visitor all the way to sanctuaries or tea-houses nestled in the tangle of trees and bushes.

Photo 16: “Take no he”

Photo 19: Fence with a geometric pattern in the gardens around the temple of Zenkō-Ji (city of Nagano – 1707). The main structure is made of round bamboo. The crossbars forming the pattern are also in bamboo, but split in small boards and attached with liana vine.

Photo 18: The Baikin mon (gate of the plum tree) of a “sukiya” garden in Sendaï, Miyagi prefecture

Tama-gaki – palisades and fences in religious compounds (drawings 5 and 6; photos 22-24) Gaki are commonly used both in the sites of Buddhist temples and Shintoist shrines. Generally, the close surroundings of the sacred places that hold the altar are enclosed with specific palisades called tama gaki beyond which access is usually restricted to priests and staff. These palisades can be either slatted or opaque.

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Images: ©Dimitri Malko 2014

Photo 17: Example of a low fence delimiting the access path to a temple in Yamagata prefecture

Gaki are made with the same perishable materials as the garden which helps them to dissolve in the environment and allows a gentle separation between the different spaces. Built according to the heights of the surrounding plants – “transparent” – these fences do not restrict the field of vision, but on the contrary give it more depth.

They permit the transition between the built and the natural: by their gentle forms and regular geometrical patterns, these fences provide the link between the house and the garden and enhance the organic forms of the garden. Photos 17-21.

Drawing 5: Front view and cross-cut of a “tama-gaki” surrounding a Buddhist compound in the middle age style (Niigata prefecture – Watari city). The fence is entirely built in hiba (a type of cypress wood growing in Japan). The lower part is cladded with grooved vertical boards, the upper part is slatted with hexagonal crossbars. The roofing is composed of clay semi circular tiles.

Photo 20: Fences in a traditional Japanese garden (Nara prefecture)

Images: ©Dimitri Malko 2014

Drawing 6: Cross-section of a traditional fence surrounding a Buddhist compound in the middle age style (Yamagata prefecture – Tendō city). The “hikae-bashira” is a diagonal brace holding a large roofed “tama-gaki”. The fence is clad with vertical boards, and covered with copper tiles.

Photo 21: Bamboo fence at the foot of a karamon or Chinese gate in Nagahama city - 1603

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Koran – Balcony fences Traditionally another type of barrier used in religious architecture, Buddhist and Shintoist buildings feature an access balcony all around the building, with a balustrade called a koran (drawing 7, photo 25).

Originally an architectural motif imported from Korea in the middle of the 7th century the koran was gradually adopted for the erection of palisades in religious

Photo 22: “Shutama-gaki”: vermilion painted low fence around the Buddhist temple on Haguro mountain, Yamagata prefecture

Photo 24: Above: A close up view of the tama-gaki from the inside showing the bolster posts.

compounds or for balustrades on wooden bridges (photo 26).

The use of stone in Japanese fences and palisades As seen in the previous photographs, some of these fences and palisades are erected on substantial stone foundations, the wood is therefore no longer in contact with the ground so decays more slowly.

Stone is only rarely used as the principal material for boundary walls, or even for parts of it other than foundations.

Occasionally barriers and fences are constructed entirely in stone examples include the ishi no tamagaki around the 14th c. hexagonal pagoda of Anraku-Ji (photo 26); hikae-bashira or bracing posts are sometimes in stone, examples include the Shintoist temple of Namura Jinja in Shiga Prefecture, and the Shintoist compound of the Tôshô-Gû in the UNESCO heritage site Nikkō, Tochigi Prefecture (photo 27).

In conclusion, we can see that wood is used at all levels of building in Japan. It is an essential material and component of Japanese architecture in a country with immense forest resources. Historically very few Japanese buildings were built using stone. From the smallest constructions, such as tea-houses, to the most important ones, such as the Daibutsu-den of Tôdai-Ji, the largest wooden building in the world, wood was

Drawing 7: A koran of a Buddhist temple in the Yamagata region.

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Images: ©Dimitri Malko 2014

Photo 23: A Tama-gaki in the Shinto temple of Namura-Jinja (national treasure - city of Ryūō – 1308). In this case, only priests can enter the area marked by the fence.

Photo 25: A Shinto temple in the compound of Hiyoshi Taisha (national treasure – mid 16th century – city of Otsu). The koran, lacquered in red, is enhanced with gilded detailing.

Photo 27: Occaisionally barriers are built entirely in stone, such as this ishi no tama-gaki around the hexagonal pagoda of Anraku-Ji in Nagano prefecture (national treasure – 14th century).

Images: ©Dimitri Malko 2014

Photo 26: Koran style balustrades in a Shinto compound near Yamagata city.

chosen precisely for its solidity, but also for its beauty and fineness.

The choice of this material has doubtlessly been chosen because of the frequency of the seismic activity in the Japanese archipelago, situated as it is on the Pacific ‘ring of fire’. Added to this is the fact that in Japan stone, a common alternative to timber; is impractical for construction, because it is either too hard or too friable. Stone is primarily used only for foundations, and occasionally for palisades and fences.

The ingenious building methods developed by Japanese carpenters and their sense of aesthetics and sophistication are truly remarkable. From an ordinary element such as a palisade or a fence they have created something unique that naturally and harmoniously integrates its surroundings.

Dimitri Malko trained in France at the “Compagnons du Devoir” (AOCDTF), working on different restoration sites in France and Russia. He spent a further two years in Yamagata, Japan as a master’s apprentice. dimitriomalko@gmail.com

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Photo 28: An example of stone hikae-bashira in the Shinto compound of the Tōshō-Gū (mid 17th century).

A Ge o m e t r i ca l D esign Wo r k sh o p : La u r i e S m i t h , R ick Collins, Nicole Co llins Editor’s Note After learning that Rick and Nicole Collins were planning to spend a week studying Geometrical Design with Laurie Smith, I asked each of them to take notes and share some of the details of their experience with readers of M&T. Laurie Before flying to the UK for Frame 2013 at Cressing Temple in Essex, Rick and Nicole Collins requested a period of geometrical study and revision with me so after Frame we shared the return car journey back to my home in Devon.

Rick’s introduction I first heard the term “daisy wheel” through a Carpenters’ Fellowship offering in 2008. For years I had been fascinated by the buildings I’d been working on in rural Illinois. Timber framing began in Illinois with the French settlers around 1680 and continued almost uninterrupted until the early 20th century. The vast forests of the Midwest had supplied Europeans and Americans with what had appeared to be an inexhaustible supply of building materials. In these timber frame structures the outward appearance and frame construction always followed some basic design rules. Whether early French buildings, early 19th century German Fachwerk frames or late American timber frames, it became easy for me to date structures by observing these rules and the materials used. Part of what I had unknowingly discovered revolved around proportional changes. Changes not only in materials but sizes of framing materials, locations of windows and roof pitches. There was something there, and I couldn’t put my finger on it. One of the main things I noticed was how many structures were based on an agricultural unit of measure called the rod. Often a wall height might be 16' 6" tall and a building might be 33' wide for example.

Laurie 33' is the first whole number in a series of fractions: 33' - 16½' - 8¼'- 4¹⁄₈' - 2¹⁄₁₆' - 1¹⁄₃₂'. Each fraction is half its greater and double its smaller neighbouring fractions.

This makes the sequence perfect for compass geometry where the radius and diameter of a circle are in the same half and double relationship. 33' divided into

half gives the 16'6"medieval Rod which, divided into thirds, also gives 11' and 5'6". These dimensions feature strongly in medieval buildings. Ely Cathedral’s nave is 77' across internally, 88' across externally with walls 5'6" thick and foundations 5'6" deep. Salisbury Cathedral is 99' across its western facade.

Rick’s introduction continued I had heard someone speak years ago about something called regulatory lines. What the presenter didn’t know, and what I came to learn later from Laurie was that this was a very simple explanation for a much deeper and much more interesting topic. The term regulatory lines is a simple way to explain how windows and doors need to line up with diagonal line across a particular elevation. What Laurie has brought forward is so much more; a system that calls out building specifications down to detailing the timber dimensions themselves.

My time working on the Gardener’s Shelter taught me the beginnings of this new language, and I feel that the time we spent with Laurie, immediately following August 2013 Frame, tied up some loose ends and has set me on the path of learning more. It was interesting and timely to attend a presentation at Cressing by Mathieu Peeters, a Danish carpenter who had been studying Japanese carpentry at a shop in California. His presentation introduced the origins and applications of Japanese layout methods. Most interesting in all of this was the concept of Kiwari – or the study of proportion. As he spoke of timber sizing, he explained that what had drawn him to Japanese carpentry was the level of detail, especially how timber sizes were ratios and related to the entire structure. He suggested – but did not say - that this intricate level of thought did not exist in Europe. I, however, disagree – I think we have forgotten it. Laurie is helping carpenters today to remember it - helping us learn this forgotten universal language again, the language of all craft, of design, of method…

Laurie A perfect example of timber sizing from the daisy wheel can be found in the design of the aisled hall, Tŷ Mawr at Castle Caereinion, Montgomeryshire. A daisy wheel one rod in diameter determines the width of the building’s nave. A hexagon drawn between the

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wheel’s six petal tips generates six spaces between the hexagon and the wheel’s circumference. The building’s two spere posts stand precisely in two of these spaces at opposite ends of the wheel’s diameter.

The spere posts are octagonal from ground to the capital and cruciform above that level, figure 1.

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AISLE

Figure 1 Timber dimensioning at Tŷ Mawr. The nave is 1 Rod wide. The daisy wheel sectors between the upper and lower petals and the full circle define the footprint of the spere posts. The upper cruciform section and lower octagonal section are shown enlarged. The outer walls of the aisles are not shown.

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Nicole’s diary Day-2 Anxious to begin training, but instead Laurie suggests we start the day with a walk down an ancient road that skirts the perimeter of the village.

Laurie identifed many plants, most notably a morning glory whose flower is a perfect hexagon.

I can’t wait to launch into geometric design stuff… but as we return to Church Lodge for a phenomenal lunch by Hilary… we begin to catch on – and realize our training was already deeply under way.

Laurie had been teaching us all morning about one of the things in our universe that regulate the forms of everything in it… geometry! More on

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Laurie Before leaving Frame, Rick and Nicole had asked to visit Greensted Church, in the maze of Essex lanes where I cycled as a youth. Inside the church we discussed the structure and proportions. Because we had no tape with us Rick paced out the nave length and width heel to toe. I measured his boot sole (13 inches) and worked out the dimensions later ~ Length 28½ Rick feet = 370½ inches = 30 feet 9 inches (to nearest whole number) Width 16 Rick feet = 208 inches = 17 feet 4 inches (to nearest whole number) The resulting floor rectangle can be defined by arcs using one rod swung from A and B or by triangulation from A and B using two equal rods, figure 2. The exterior and interior of the north wall are shown in figure 3.

1 ROD 16½ FEET

Nicole’s diary Day 1 Travel from Cressing Temple to Sutcombe in Devon.

Our training began at Saint Andrews Church at Greensted juxta Ongar in Essex. This is the oldest wooden church in the world built from vertical, originally earth fast, oak staves in about 1060. The staves are half tree trunks with their diameters forming the flat interior walls, each stave rebated and joined to its neighbouring timbers by slips fixed into the rebates. Measured the surface mounted rim lock on the front door and later confirmed it conformed to daisy wheel ratios. A nice road trip across England including past Stonehenge on the A303, with a few stops along the way. Arrival at the Church Lodge. Dinner by Hilary: Homemade Pizza!!! We start our discussion of the daisy wheel that night over dinner.

AISLE

Figure 2

B

Laying out the proportions of Greensted Church floor using a single rod, upper drawing, and two identical rods, lower drawing. The rod length is a matter of choice.

Figure 3 Saint Andrew’s Church, Greensted juxta Ongar, Essex UPPER PICTURE The north wall of the Saxon stave church, probably originally earth-fast. In the Victorian period the presumably rotten feet of the timbers were cut and underpinned with a brick plinth.

LOWER PICTURE The flat diameters of the halved logs line the interior of the north wall with the tiny leper’s squint cut through the solid timber. The axe (or adze) work is clearly visible on the timbers.

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the many ways forms are expressed or manifested, through circularity, angularity, harmonies achieved in opposites, similars, colors… More on the motivations of humankind to acquire knowledge, observe the visual and structural language of our world… and then to develop these observations in order to communicate and create deep meaning in what we construct. Laurie also speaks of the welldocumented Greek and Roman ideas of symmetry and structure in building. Our discussion continues through dinner and suddenly it’s 10pm.

Laurie Circularity and angularity are the two opposing yet inter-related aspects of geometry in natural forms. We find circularity in the spheres of the Earth, sun and moon, in the section of trees and, of course, in the spheres and circular irises of our own eyes. We find angularity in the mineral world, in the triangular, square and hexagonal sections of crystals. In medieval architecture this harmony of opposites is expressed in the alternating circular and angular piers of cathedral and church arcading.

The supreme example is Durham Cathedral where the circumference of the cylindrical piers is equal to their height, thus making their surface area a square. The square is set out with diagonal lines that are either chevroned, cross hatched to form a diagonal pattern of squares, figure 4, or spiralled with every line rising diagonally from the cylinder’s base.

In his Ten Books on Architecture the Roman architect Vitruvius, who lived around the time of Christ, states that the design of a temple depends on symmetry, the principles of which are due to proportion. Proportion is a correspondence among the measures of the individual members of an entire work, and of the whole, to a certain part selected as standard. This is a similar concept to Kiwari so the intricate level of thought that Rick mentioned above was alive in Europe 2000 years ago. Leonardo da Vinci’s Vitruvian Man shows how the human body relates to both circle and square, figure 5.

Nicole’s diary Day-3 We visit Saint Andrew’s Church through the lych gate beside Church Lodge. We see quatrafoils in the carved oak pews; geometrical design in the windows, column capitals, placement of doors, arches…

Laurie Saint Andrew’s Church has a nave and two aisles, the Soldon and Thuborough aisles, built as chapels by wealthy local families. The Thuborough aisle, has a date stone IB 1630 RB set into the gable wall.

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Figure 4 Durham Cathedral cylindrical pier proportions with the pier’s height equal to its circumference.

A simple experiment proves the point ~ cut a circle of card the same size as the circle on the pier and mark a point on the circumferece, stick a needle (axle) through the centre of the circle, start with the mark at the base of the column and wheel the circle up the arrowed line to the mark at the top. Note that in the photograph the column tapers towards the top. This is visual perspective and the real column is a true cylinder.

The individual stones are double squares cut to a predetermined pattern using templates.

2 R O D S 3 3 FEE T

ET FE 38 Figure 5 Leonardo da Vinci’s famous drawing.

There is a daisy wheel carved inside the 0 of 1630, figure 6. The date stone is also a design icon, a visual clue to the design method applied in the chapel’s construction: the Thuborough aisle is set out to daisy wheel geometry and has a 33' x 19' footprint, exactly the same as Shackleton’s Nimrod Hut, a knock down kit building made in London for assembly in the Antarctic 270 years later for the 1900 expedition.

Nicole’s diary Day-3 continued We learn about five circle geometry, and look at the beautiful design of a 1460’s Welsh aisled hall Tŷ Mawr at Castle Caereinion in Montgomeryshire. This one clearly has its post and truss dimensions and positions called out through five-circle geo.

Laurie The design of Tŷ Mawr evolves from a single geometrical symbol that was carved into the inner face of the eastern aisle post at the northern end of the house, a symbol that was recorded in a scale drawing and on a video clip but lost during the “restoration” of the building. Like the Thuborough chapel date stone in Sutcombe, the geometrical symbol at Tŷ Mawr is a design icon that provides the fundamental geometry from which the building’s floor and section, including roof pitch, can be designed, figure 7. (overleaf)

19 FEE T Figure 6 IB 1630 RB datestone and design icon set into the gable wall of the Thuburough chapel at Sutcombe Church, Devon. The chapel is laid out in daisy wheel proportions with the rectangle’s long side at 33 feet (a double Rod) and short side at 19 feet. The short side equals the circle’s radius so the rectangle’s diagonal and circle’s diameter are 19 x 2 = 38 feet.

Nicole’s diary Day-3 continued We move on to explore the layout of Ely Cathedral (1181) by drawing the crossing and transepts using five circle geometry using an old school chalk compass on an 7 x 3½ feet blackboard on the dining table, figures 8 and 9. We go on a 5-circle diversion finding related proportions: drawing methodology for a perfect square, diamond, whirling squares, ocatagon and maltese cross, etc. Then back to Ely, developing a triple daisy wheel sequence along the nave followed by an angular subgeometry of diamonds, with both defining the locations of the cylindrical and angular piers, figure 10.

Then, with Ely behind us, we take a look at Islamic traditions. All design begins with a circle - symbolic of eternity or god. We discuss the harmonies of similars and opposites, the color relationships of patterns and their balance within the environment. The psychology of how space separates as we experience a structure and move through it. Now on to drawing the golden rectangle and logarithmic spiral! Patterns of natural

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A

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Figure 7 UPPER DRAWING Setting out the 5 circle geometry that defines Tŷ Mawr’s nave and section. The perpendiculars are drawn first and the central circle is drawn from their intersection. The east and west circles are drawn to the same radius from the central circle’s poles. B The north and south circles are drawn to the same radius from the central circle’s poles. C The radius of the small arcs are drawn to the same radius as the full circles. The compass pen is placed at the intersection marked by the black arrow and the pin on the perpendicular. This is repeated for the remaining arcs.

LOWER DRAWING The video still of the carved symbol at Tŷ Mawr, left (© Clwyd-Powys Archaeological Trust), and its function as a design tool to establish the roof pitch, right. It can be seen that the roof height from tie to ridge is equal to the full circle height and that the pitch runs precisely through the small arc intersections marked by black arrows. It is also clear that the carving is a shorthand of the full 5 circle geometry but utilising only the necessary central core. growth, figure 11. A lunchtime trip to the beach. Hilary said that we are working ourselves too hard and we need a break! We drive to Morwenstow and walk out along the cliff top to eat Cornish pasties in the cliffside hut constructed from driftwood by Reverend Hawker, around 1840.

Laurie Hawker was a renowned eccentric who dressed up as a mermaid, excommunicated his cat for mousing on Sunday, built his vicarage chimneys to match his favourite church towers, smoked opium and wrote sermons and poems in the cliff top hut.

Through the open stable door we face the Earth’s curvature on the Atlantic horizon, part of a 24,900 mile circumference drawn from a 3,959 mile radius,

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Figure 8 Setting out Ely Cathedral 5 circle crossing.

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B Figure 9 Setting out Ely Cathedral crossing using 5 circle geometry.

A The basic 5 circle geometry, left, allows tangents to be drawn across the circles to generate the perfect square, shown in blue tone, between the intersections of the four outer circles. Within the square there are eight further intersections, in pairs adjacent to each side of the square. Parallels, shown in green line, are drawn through these intersections. B The parallels, right, define the wall thickness, shown in grey tone. The geometry of the ends of the transepts and choir are not shown.

Figure 7

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UPPER DRAWING Setting out the 5 circle geometry that defines Tŷ Mawr’s nave and s A The perpendiculars are drawn first and the central circle is drawn from their intersec and west circles are drawn to the same radius from the central circle’s poles. B The no N Ocentral R TH circle’s poles. C The radius of the circles are drawn to the same radius from the TR A N E PT drawn to the same radius as the full circles. The Scompass pen is placed at the intersect the black arrow and the pin on the perpendicular. This is repeated for the remaining a LOWER DRAWING The video clip of the carved symbol at Tŷ Mawr, left (© Clwyd-Powy cal Trust), and its function as a design tool to establish the roof pitch, right. It can be s roof height from tie to ridge is equal to the full circle height and that the pitch runs p the small arc intersections marked by black arrows. It is also clearCH that O IRthe carving is a the full 5 circle geometry but utilising only the necessary central core.

AISLE N AVE

S O UTH TR A N S EPT

Figure 10 Setting out Ely Cathedral nave using daisy wheel geometry.

The centre line and wall alignments established by 5 circle geometry can be extended to allow for the development of the nave geometry. Three inter-linked daisy wheels are drawn to fit the internal dimensions of the nave (77 feet) and an angular sub-geometry is drawn between the wheels vertical petal tips and the centre line, in dashed black line. The intersections define the alternating locations of the cylindrical and angular piers in their perfect harmonic interchange of circularity and angularity.

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A

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D C F Figure 11 Drawing the golden rectangle and logarithmic spiral.

LEFT DRAWING The drawing starts with a square ABCD which is halved. The diagonal of one half is used as a radius to draw the magenta arc down to the square’s base line at F. The square is extended to E and F. The large rectangle AEFD and small rectangle BEFC are both golden rectangles. The side EF is simultaneously the short side of the large rectangle and long side of the small rectangle and it is this that gives the two rectangles a harmonic relationship.

RIGHT DRAWING Starting with the original square, a series of diminishing squares, shown in blue tones, are drawn within the two rectangles. A series of diminishing quarter circle arcs, drawn in each square, link to form the logarithmic spiral. At the axis of the spiral the accuracy of the drawing fails and this small area is shown in Greek volutes by a plain disc that was known as the eye of the spiral. circularity on a grand scale seen through the human eye’s circular iris.

Nicole’s diary Day-4 Further down the coast at Sandymouth we walk along the sand and listen to the roar of stones as each wave drags them back down the beach. Laurie points out Devon Rag roof slates – roofing tiles that are locally quarried and distinctly wide. But mostly, we see geometry everywhere. In Saint Morwenna’s church we find daisy wheels around the capital of one of the Norman arcade piers and 5 circle geometry on a carved oak pew end, figures 12 and 13, and the star of David and pentangle of Solomon in the Victorian stained glass. Outside we find geometrically patterned cut slates used to protect the bargeboards on the weatherbeaten gable end of the church, Celtic spirals in the cemetery, symmetry in the foliage around us.

Back at Church Lodge, it’s another phenomenal dinner and then some time in Laurie and Hilary’s impressive library to look at books and revisit Tŷ Mawr. Our meals were fantastic and our lodging very comfortable. We spent many hours asking questions about all manner of things. Laurie and Hilary were fantastic hosts and indulged our every need. This is truly a once in a lifetime experience and an incredible offering by two of the most talented people I have met.

Then it is time to wrap-up. A last look at the delicately carved geometrical church tracery panels hanging on Laurie’s wall and then, at 10am, we all head out to

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Drewsteignton on the edge of Dartmoor where we meet up with Oscar, Joel and Samantha Hendry for lunch in the sunlit pub garden (Google Emmanuel Hendry to see examples of their carpentry). After a great lunch we say our farewells and go our different ways.

Laurie Nicole’s comments are very generous. The truth is that Hilary and I learned as much from Rick and Nicole as they did from us. We enjoyed their visit immensely and, as always, it was a great opportunity to expand our knowledge of each others’ cultures.

Laurie Smith has been researching the geometry of timber frames for 25 years and is the author of The Gardener’s Shelter at Cressing Temple and The Dutch House at Bucksteep Manor.

Rick Collins is a journeyman timberframer of 17 years and owner of Trillium Dell Timberworks; a custom frame shop that specializes in heavy timber restoration and the utilization of local resources in new structures.

Nicole Collins is a carpenter of 12 years, focusing on restoration work – and a new entry in the Timber Framers Guild Apprentice-Journeyworker Program.

PAULCARPENTERASSOCIATES Consulting Civil & Structural Engineers web: www.paulcarpenterassociates.com

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TH E C O V E R I M A G E S Front Cover Detail of a Temple Rafter in Luang Prabang, Laos. David Leviatin Back Cover Walking a Frame in Australia. Chris Nance