Thesis-Danish timber building

Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

7th semester Dissertation: Title: Danish Timber Building Author: Yi Lin Class: 7I E-mail: mail: vincentyilin@gmail.com Advisor: Lars Hartmann Petersen Program: Constructing Architect Institution: Copenhagen School of Design and Technology Address: Lersø Park Alle 2 2100 Copenhagen, Denmark Date: October 16th, 2010 Cover photo: 2003, Den Gamle By i århus, painted by Aleksandar Hajder

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Contents 1. Preface................................ ................................................................................................ ............................................... 4 Why Danish timber building...................................................................................... ...................... 4 The word of gratitude ............................................................................................... ................................ ............................... 4 2.

Introduction ................................................................................................ ................................ ....................................... 5

3.

Wood as building material ................................................................ .................................................. 7

History ....................................................................................................................... ................................ ....................... 7 Type of wood ................................................................................................ ................................ ............................................. 7 Where does the timber come from? ................................................................ ......................................... 8 6.

Ancient timber building worldwide ................................................................ ................................... 13

7.

Modern timber house worldwide ................................................................ ...................................... 15

8.

Why are there so few timber projects in Denmark today? ................................ 17

9.

Historic development of timber building in Denmark ....................................... ................................

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Palisade (Palisadevek) ............................................................................................. ................................ ............................. 18 Bole house (Bulhsuet) .............................................................................................. ................................ ..............................19 Stave construction (Stavrek) ................................................................ ....................................................19 Timber-frame frame construction (Bindigsværk) ............................................................... ...............................19 National Open Air Museum of Urban History and Culture (Den gamle by) ..............21 Building construction between 1700 and 1950 ......................................................... .........................23 Jørn Utzon& Espansiva ............................................................................................ ................................ ............................ 23 CASA NOVA ................................................................................................ ................................ ............................................25 Sortemosen ................................................................................................ ................................ .............................................25 10. Constructive wood protection: Fire protection by design ................................ 26 Typical fire protection technical Details (figure 38). ................................................. ................................

27 11. Constructive wood protection: Preservation by design .................................... ................................ 28 Exterior wall detail ................................................................................................ ................................ .................................. 28 Distance to the ground ........................................................................................... ................................ ........................... 29 Drip nose and water flashing................................................................ ................................................... 29

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Eaves ....................................................................................................................... ................................ .......................30 Foundation detail................................................................................................ ................................ .....................................30 Timber components assembly ................................................................ .................................................30 12. Other Timber constructi0n method can be found in Denmark..........................

Denmark.......................... 31 Platform framing ................................................................................................ ................................ ..................................... 31 Balloon framing ................................................................................................ ................................ .......................................32 Plane Construction ................................................................................................ ................................ ..................................32 Solid wood wall system ............................................................................................ ................................ ............................ 33 13. Timber building is our future!................................................................ ............................................ 33 Thermal protection ................................................................................................ ................................ ..................................34 Durable: ................................................................................................ ................................ ...................................................34 Renewable ................................................................................................ ................................ ...............................................34 Sustainable ................................................................................................ ................................ ..............................................34 Healthy ................................................................................................ ................................ .................................................... 35 14. Conclusion ................................................................................................ ................................ .......................................... 35 14. Bibliography ................................................................................................ ................................ .......................................36 Books: ...................................................................................................................... ................................ ......................36 Publish: ................................................................................................ ................................ ....................................................36 Visits: ....................................................................................................................... ................................ .......................36 Illustrations: ................................................................................................ ................................ .............................................36 WebPages: ................................................................................................ ................................ ...............................................39

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

1. Preface This dissertation report is written by 7th semester Construction Architect student Yi Lin, form Copenhagen School of Technology in the early autumn of 2010. Danish timber building in different period have created colorful and diversified building styles with rich and deep cultural connotation. This dissertation report is focusing the attention on both ancient and modern timber building system in Denmark, by analysis of the Danish timber timbe building history and technique, architecture esthetic, esthetic attempt to present the possibilities for using timber this material as well as evaluating new future. This paper has now been revised and adapted for the English-specking world.

Why Danish timber building Personally I am very fond of timber construction projects. Timber buildings are not only the most economical and environmentally-friendly; environmentally they also provide the best platform for integrating modern technology systems like controlled ventilation and an air extraction, heat recovery and solar panels. While I was having my internship in Ă…rhus, I travelled around Jutland, there is one theme park called den gamble by, it was quite impressive. I believe it could be interesting for me if I can get an insight of Danish timber building construction technology and historic development. development As a foreigner student in Denmark, particularly, I am form remote Asia; however I would like writes and makes some research about Danish timber building, building to qualify my bachelor degree value in Denmark. Danish timber building has a long history and rich content. Of course, in the world where were thick forests, such as China, Turkey, Sweden and Japan have very splendid and profoundness culture, with each geographic eographic area developing its own style and process, but timber building development in Denmark takes a modest place. Danish timber building with peculiar characteristics has witnessed a long story of this magical fairy tale world-Denmark.

The word of gratitude I would like take this opportunity to express my deep sense of indebtedness to my supervisor pervisor Lars Hartmann Petersen who read through the whole the manuscript and given me useful corrections and comments, Furthermore, Furthermore I also like to give an extra special thank you to my entire teacher for their valuable guidance, suggestions and

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

outstanding mentorship during I write my paper. This dissertation could not have happened without the help and support of all those people.

Yi Lin Copenhagen, 2010 autumn 2.

Introduction

“Timber building is part of future energy-efficient energy efficient building. Wood is sustainable, CO2 neutral and a highly effective insulator, creating excellent living conditions.

One specific advantage of wood is its ability to reduce energy use. Timber construction has a higher heat insulation value than conventional construction methods, even with lower wall thicknesses. An external external wall constructed using timber may have only half the thickness of a brick or concrete wall, yet provide double the thermal insulation value, while at the same time avoiding the thermal bridging common with other construction methods. Considering the growing grow importance of energy-efficient efficient building methods, timber construction will play an increasingly important role in the future.�1 From the first timber building in early medieval age, to the modern timber house today, through the knowledge form history and a development, I can illustrate some of problems and advantages that many timber building today, and furthermore look at the modern Danish improvement proposals, find out if we can help give the Danish timber building a gracious, adorable charity, everlasting safety, infinite brilliant, new Golden Age. I wish is to write a specialization report can be used by other constructing architects and others within the field of planning, architecture and construction, or anyone who w has a special interest to Danish timber building but who lack specialist technical knowledge.

The following aspects will illuminate in this dissertation: di Timber: deposits, characteristic and its potential History and development: timer building construction method and significant project

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Dipl.-Ing. Ing. Markus Julian Mayer (Architect BDA) and Dipl.-Ing. Dipl. Ing. Cathrin Peters Rentschler, Munich, Germany

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Technology: preservation and fire protection Problem demonstrate: deformation of timber construction Important issues discussed in this dissertation: What are the advantages and disadvantages of timber by compare and analysis different construction material? mat What is the advantages make timber-frame timber is the main frame of timber structural technique in Europe today?

What has caused the timber construction building almost disappeared once in the Danish building history?

What kind of timber building system still can be found in Denmark toady?

What is interesting detail of timber building?

What is the development blueprint of timber building in the coming decade? deca

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

3. Wood as building material Wood are mainly composed of long cells stretched vertically, forming wood fibres.This structure gives timber elasticity and strength. A cross section of a tree trunk divides into bark, bark baste, heartwood, sapwood and pith. (Figure 1) The growth rings in a tree are visible because summer wood is darker than spring wood. Wood is composed of cells, make up of a cell wall, most cells are long in relation to their width and are aligned axially along the trunk.

History Wood was human`s first structural material predates written history, it has been used for a greater number of products than any other matial,it is probably the most versatile material, can be used as most of structure, The oldest known timber building in existence is Horiuji temple in Japan, which was built of cypress in AD607.

AD607 “The only material which is sustainable, structural, and beautifully adaptable to so many building requirements, is timber.” timber. 2 Except earth, wood is the oldest building material in the world. “For thousands of year’s wood has been the most conventional building material along with stone and clay. For decades wood has played a key role in the construction of road system, system bridges,, railroads, and the 3 construction process of most buildings.”

Type of wood Two basic categories of wood use for most commercial projects are recognized: Hardwoods, softwoods (Figure 2).

2) Softwood is obtained form an evergreen or coniferous tree.

Hardwood is obtained comes from deciduous or

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http://www.owdman.co.uk/joinery/sust.html

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”Materials for design” by Vitoria Ballard Bell

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

broad-leafed leafed tree, The Scandinavian forests are cultivated and harvested to provide a continuing supply of softwood timber to northern Europe.

Softwoods Used for framing,sheathing,paneling Alpine fir, Douglas fir, Eastern spruce,Englemann spruce,Larch,Lodgepole pine, Mountain hemlock, Red spruce, Sitka spruce, Western hemlock, Balsam fir, Eastern hemlock, Eastern white pine, Idaho white pine, Loblolly pine, Longleaf pine, Ponderosa pine, Shortleaf Shortleaf pine, shortleaf pine, Southern yellow pine, White spruce.

Used for Moldings, Window and door frames Ponderosa pine, sugar pine, White pine Used for Finish Flooring Douglas fir, Longleaf pine Used for shingles,siding,outdoor structures California redwood, dwood, Southern cypress, Western red cedar, white cedar Hardwoods Used for Moldings,Paneling,Furniture, Moldings,Paneling,Furniture Beech,Blackwalnut,Cherry,Mahogany,Redoak,Teak,Whiteoak,Ash,Birch,Butter walnut,Cherry,Mahogany,Redoak,Teak,Whiteoak,Ash,Birch,Butter nut,Lauan,Pecan,Rosewood, nut,Lauan,Pecan,Rosewood,Tupelo gum, Yellow polar Where does the timber come from? from

Timber comes from trees, timber is a sawn wood, a material obtained from trees; most timber comes from Pine trees. Pines grow really rapidly and can be harvested every 7 years or so for the timber. “Every year the world’s forests deliver up over 1.5 billion cubic meters of timber for milling and industrial processing, as well as supplying fuel for about half the world’s population. This timber can come from 4 forests that grow naturally or from plantations.” planta The production of timber, begins with felling of trees and transport to a sawmill, then wood can be dried to any desired moisture content. There vary range of differences in shrinkage rates can be adapted to the building design. The following illustration tration depicts the process of “where does the timber come from” (Figure 3).

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”Timber” Edited by Waitakere City Council

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

4. Wood rot problem Wood is the only building material that is biodegradable and reusable. reusable When a tree dies, it is biologically degraded by fungi and insects. The nutrients contained in the

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

wood enrich the humus, which stimulates the growth of young trees. Growth and degradation are part of the natural cycle.

Below two areas of timber rot found in the DK are addressed, dry rotss and white rot.

Dry rot is typical wood destroying fungus; due to almost all the wooden rotting fungi require moisture for germination, growth and survival, so the name Dry Rot might be inappropriate. Because the weather of Denmark is so damp, big economic losses is caused by fungi rot.

“Dry-rot rot fungus is often thought of as a building cancer, rampaging through hrough buildings and rapidly destroying any timber in its path.”5 dry-rot rot gunges living in masonry and eat the wood, it can occur in the someplace elusively, for instance, between the timber paneling, under the floor voids. To avoid the dry rot occur, must keep good ventilation and ensure the timber in a property does not become damp, damp If the dry-rot rot fungus attack the timber to make it crack cubical manner; the wood also goes slightly darker in colour.( figure 4) “Compared Compared with dry rot, wet rot is hardly a problem problem ! It is basically the timber decaying naturally in the presence of high levels of moisture. There is almost always a structural defect causing the problem, it may be that the wall adjacent to the timber is suffering from damp, or water collecting on the timber. Any structural problem must be tackled at the same time as the timber is treated otherwise the problem is likely to reoccur.” 6The cheapest and most effective way to prevent wood decay is of course to keep the wood dry.

Must be aware of any roof ro place like roof trusses and roof joint ,they are very easy have wet rot occur, if any hole in the roof allow rain water coming into the roof structure. Bath, kitchen sink, and toilet, shower and place behind the washing machine are also the web-rot rot fungus favored places. Most of rotten timbers must be removed or replaced, it depend the how big the damaged area. (Figure 5)

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http://www.diydata.com/problem/timberrot/timberrot.php

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http://www.diydata.com/problem/timberrot/timberrot.php

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Where timber is in connection with brick walls there is risk for fungus. fungus. (Figure 6)

Comparison of fungi found in publications from the Nordic countries. (Figure 7) The data are given as relative occurrence of the most important fungal species/genera/groups in %.( %. figure 16).According to the date, Brown rot fungi were the dominant decay type (77.4 %) among the the fungi found in Norwegian buildings.

Serpula lacrymans (16.0 %) and Coniophora puteana (16.3 %) were the most frequently identified species. Other frequently found genus and group categories were Antrodia spp. (18.4 %) and soft rot (15.8 %). Wall damage was generally most common among the recorded decay fungi (18.3 %), followed by floor damage (13.4 %) and roof constructions (8.8 %). Generally, the same fungi are found in Norway, Denmark and Finland, with Serpula lacrymans and Coniophora puteana as the most commonly identified fungi.

5. Wooden insect attack problem Timber building or component can be easily damage by insects in different ways. There is the figure of wood boring insect life cycle. It takes 6 week form Larva to adult (Figure 8).

Furniture Beetle, Longhorn Beetle and Death watch Beetle is quite common to see in Denmark.

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Danish Timber Building

Yi Lin

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KEA - Københavns Erhvervsakademi

Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

6. Ancient timber building worldwide “Cut Cut stone, marble and brick are the building blocks for monumental religious architecture, city walls and fortifications, palaces and great civic buildings, and provide a powerful visual link to the past. There is, however, also a strong tradition of architecture tecture which makes use of one of a far more practical and curiously durable material, and one which endows those same urban centers with access to a different, more intimate history. That material is wood”. wood 7 China Ancient China have own indigenous timber system of construction which relevant to principal characteristics form prehistoric times to present day. The timber construction in China is remarkable part in Chinese civilization. In order to support huge roof, they use heavy timber structure,usually use trimmed log as load-bearing load beams or column to transfer the load form roof to foundation. This is a picture of one palace in Forbidden City, which involves very complicated timber housing technique (Figure 12).

Japan Throughout Japanese long history, story, timber building dynamic developed create a lot unique and indigenous in Japan. Hipped-gabled roof of ceramic tiles, post and beam system are also quite common to see in Japanese temple. Therefore, Buddhism is quite widespread thought out the whole Japanese apanese history. Some of timber temple just base on the mountain. This is picture of Yakushi-ji, originally built in 730(Figure 13)).

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WOOD CULTURE AND TIMBER HOUSES Edit by Andrew Finkel

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Norway Norway has gorgeous timber industry over a thousand years, even today, the classic Norwegian log cabin still popular. Timber house developments have very strong Scandinavia vernacular architecture. The first stave churches were built in the 10th and 11th century. This is one of best preserved church in Norway (Figure 14).

Storey-divided divided steep shingle roofs with good eaves and sharp edged ridges protect main post –structure.

Turkey Turkey has extraordinarily long and well-documented well history of timber house. Wood apparent is the building material of choice before the First World War in Turkey.

In 1890, there is a 6-storey storey timber hostel by “Wagon List” at Buyukada in Turkey(Figure 15) .During During first world war it was for military school and later for refugees. After the war, this building again used for home and school for orphans.

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

7. Modern timber house worldwide “Those architect who promote the use of wood hope their efforts will encourage people not just to cherish old buildings but to use the knowledge those buildings b 8 encapsulate to create new traditions” Wood is increasingly used in different kind of function of project.

Garden House Location: Czech Republic The intention of architect: create a house that best fits the existing site shape with a tectonic clarity. The main structure consist continuous concrete foundation and rest part of building built by entirely of wood (Figure 16).

Commercial and residence building Location: Germany The intention of architect: create a multistory house that fits contextually into the character of village. Through the use of a movable larch wood slat wrapping, the house is able to achieve a lightness and softness while creating an ever-changing ever façade(Figure1 (Figure17).

Mountain villa Location: USA The intention tion of architect: with spectacular 360 degree view to valley, on the wooden terrain can really enjoy the irresistible charm form mountain(Figure (Figure 18).

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WOOD CULTURE AND TIMBER HOUSES Edit by Andrew Finkel

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Hotel Location: Finland The intention of architect: with experimental shapes, only use finish wood into housing design. Architect Pieta-Linda Linda Auttila hopes to spark interest in wood and highlight its role in building and design(Figure (Figure 19).

19)

Farm Location: Netherland The intention of architect: A wooden box with an open façade system for most part of building, allowing the wind to ventilate the whole farm continuously(Figure continuously(Figure 20).

20)

Pavilion Location: France The intention of architect: temporary entrance-pavilion entrance for huge square, massive vertical wooden panel attracts tourist attention attention(Figure 21).

luxury residential Location: Lithuania The intention of architect: Dark wood cladding covers though whole face to make contrasts with spectacular views of massive grass. Whole structure is stick out form ground level (Figure 22).

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Cabin Location: France The intention of architect: The interior finish is smooth and stripped down as to contrast with the traditional look of the external log cladding (Figure 23).

8. Why are there so few timber projects in Denmark today?

In Denmark, until the 1700’s, 1700’s almost all the construction was primarily masonry and timber. Denmark was covered with forest; the price of wood was inexpensive. To know and have some basic carpenter skills is universal for Dane at that time. Timber house is very popular at that time, but come to period of Christian IV of Denmark ruled, the king of Denmark and Norway Christian IV who energetically promoted trade and shipping, most of forest resource is used to build ships. The masonry architecture style for instance Dutch Renaissance came from south, so at that time people start to quit timber structure building. There is one more important reason is that Wood is quite flammable material. Copenhagen was plagued by fire in the 17 centuries. Other structure materials material are come out, like steel, concrete available for commercial and residential projects. Brick has been become a predominant material for the façade and roof in last several hundred years in Denmark. Over the past three decades, most Danish Dani construction work use concrete with reinforcement bar as main construction material. material Along with Danish architecture and modern fire protection technology development, timber house is making a comeback .Since 19 century, Denmark has not been build any multistory timber house .CASA NOVA consortium build the first multistory timber house in Hørsholm and Herning.

According to its public data shows it has increasing percentage of share on the market occupies. That is because it expresses the strong, sustainable and full of various characters in its creation. With its unique qualities of form, color, and structure, wood is most reliable building material at the core of architecture. As a building material, timber imber is valued for its character, warmth and texture, it give a unique aesthetic, a natural fragrance, and a general “environmental” connotation unlike any other material by leaving a natural material exposed in a recognizable state. More and more Danish architect used timber construction to enhance the architecture aesthetics and special appearances. You can see form some luxury residential, lodges and mountain hotel and so on.

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

9. Historic development of timber t building in Denmark “The first mention of buildings constructed complete from timber in European history is in Tacitus. Tacitus writes about Germania houses in his histories in AD 98, 98 characterizing them as something not pleasing to the eyes, the house had either palisade walls with columns fixed into earth or clay-clad wattle walls. Excavations from a Stone Age village in Schwaben, Schwaben Germany, showed that houses like these have been built over a period of at least 4000 years.”9 Timber has been used for building houses for centuries and there are many historic timber houses still use today. Since remote times, Northern Europe and Scandinavia are characterized by large forest areas.Archaeologists already tell us the oldest existing timber building in Scandinavia Scandinavia is the Borgund church in Norway, built in the twelfth century.

Denmark has no so strong timber building culture like for example east Europe, Asia and the rest of Scandinavia. Here you can see Palisadevek, Bulhsuet, Stavrek, and Bindigsværk from top to bottom (figure 24).

Palisade (Palisadevek) But the first trace of a timber structure can be dated back to the Stone Age. One of the first wayss to construct a timber structure is palisade, p where sharpened wood piles were dug into the soil side by side. This is way to keep the structure upright. But this system was abandoned in the late Middle Age. The crucial reason is that material consumption is considerable. considerable

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Timber in Construction Edited by John Sunley and Barbara Bedding P105

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Bole house (Bulhsuet) It is documented that the BULHUSET as "type of house" in Denmark, dates back to medieval time.6 bole houses house remain form middle age can be found in Denmark.

Those entire bollll house dispersed over in Kiplev, Tandslet,, Varnæse, Søllested, Birket and Svenstrup. The best preserved bell house existing at Birket.

Birket The oldest bole house existing at Kiplev. To keep durability of bell house, it must keep a continuous maintenance of it.

Bole Houses are characterized by the fact that they are made of wood, entered a bar work. The houses have vertical bars, called notes; the sides where the underlying horizontal planks, 'bulfjæle' are inlaid. Main structure of this bole house is stone foundation combine with oak post. The bole construction was replaced by the Half-timber timber construction later on.

Stave construction (Stavrek tavrek) Other variant of this building system is Stavrek which have the supporting bars instead of underlying horizontal planks. The vertical supporting bars can be fit together as wall. “This This is a braced skeletal construction filled with boards or plank tongued into a bottom and top plate. In modern post and lintel construction the space between is usually filled with boards and insulation which also braces the structure. The timber components are heavy and well-suited to recycling, providing provi 10 that appropriate methods of fixing are used.”

Timber-frame construction (Bindigsværk) ( Until the” Bindigsværk” indigsværk” came into the sight,the condition of utterly timber construction drop down (figure 25). In Denmark, the bole and other old timer systems were replaced by the timber-frame timber construction. There is a distinct relationship between bole house and timber--frame house construction, which often differ merely in that the spaces in the walls were filled with boards or with plaster and 10

The Ecology of Building materials by Bjørn Berge P 232

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

bricks. Thus thee bole house forms a natural connection between building methods so apparently different as stave-work, stave log-work, work, and half timber, reveals the mutual influences that must have been at work from the very moment they encountered one another in Scandinavia, The oldest half-timbered house in Denmark, which is also the oldest dated non-nobility, non and non-religious religious building of the Nordic 11 countries,, can be found in Køge.

Timber-frame frame building system is a traditional method of building with timber, all the individual pieces assembly on site storey by storey.

Whole system combines with roof element, load bearing post, separating functions frame foundation and suspension floor. Here you can see suspended floor between normal storeys and over basement (figure 26). frame was a very common technique, obviously in countries “In fact, the timber-frame with a great availability of wood, for its constructive and structural features: it was a “simple” way of building for the little dimensions of timber elements that could be easily moved from a place to another”12. The advantage of thiss building system is that it does not ot need massively wood.Only use timber as main frame.Later frame. on,when brick become more and more popular,together with some monks who came form south to north,there came to new technologies ,such as brick-burning brick burning and window glass.But using ties still expensive expensive compare to timber,even timbered area has been used up in the end of 20th century.”There century. There are three features about timber frame seismic-resistance, resistance, economy, and strength.. the first one is the good aptitude in absorbing different kind of “building faults”, as the use of deformed elements or smaller than requested ones, or some unfit connections; the second feature is the way of responding to several failures during building’s life, related to foundations, posts or floors; finally, we cannot forget that builders builders could easily replace damaged elements with new ones. We could resume these qualities identifying the

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http://wapedia.mobi/en/K%C3%B8ge

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Timber-Frame Frame Buildings in Scandinavia: High Deformation Prevent the System from Collapse Edited by Pietro

Copani

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

timber-frame frame as “adaptable”, and maybe it’s just this adaptability the main reason of the success of this constructive method in so many different countries coun and 13 centuries.” Timber frame construction construction is the dominant structural system in the timber building industry today.

National Open Air Museum of Urban History and Culture (Den gamle by) Den gamle by definitely is one of most popular museums of Denmark. By collecting 75 houses in one village form last 500 years of Danish history. Most of them are timber frame house. There are real houses have been taken down and rebuild by moving from 24 different cities in Denmark. And this museum village still is constantly enlarged.

Most of old house in Den gamle ga by are timber framed house by a traditional way of filling spaces with brick. Here you can see a perspective view about Danish timber house in Den gamle by (figure 27).Once 27) the main structure is assembled on site, the wall can be done by in-filling filling between wooden members with some natural building materials such as cob, planed wood, straw and cordwood, or by wrapping the structure with insulation and siding, which creates a light and tight building buildin envelope14. In Denmark, the traditional infill-frame infill constructions can be described: the timber cage locate on masonry foundation with kind of module, the vertical wall raise up two storey, the beam and post framework supports the roof by transferring rooff loads to basic posts and into foundation of the house. To sum up, the success results is make self-supporting supporting and durable structure with a large open living space, which have well maintained indoor climate like easy to heat up and cool down, also have better tter natural light energy-saving energy environment.

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Timber-Frame Frame Buildings in Scandinavia: High Deformation Prevent the System from Collapse Edited by Pietro Copani 14

The art of Timber framing

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Walk into museum, we can see some nice wooden carved on the timber frame (figure 28).

“The The most interesting expressions of Danish half timber structures were built since XVI century, when the carpenters get g a formidable skill in rising frames, characterized by strength and beauty because of some improvements like the standardize of carved wood elements, or the great variety in posing bricks, that makes the houses’ surfaces like a series of different fabric panels. These two features are not just decorative ones, but they take part in the whole constructive system, with a specific role. In fact, the wooden pieces posed next to the first floor’s posts often give their surfaces for decorative carvings as flowers flowe or suns, but they also provide rigidity to the structure, connecting the right angle formed by horizontal and vertical elements”.

If you really going around into the museum, you probably realize one interesting detail of timber frame house. Some timber houses have varying degrees of deformation. There is one example shows massive deformation on the timber building in the museum (figure 29).There There is one common reason is sinking foundation or pillar or may other part of building, it may because a pillar failure or foundation failure ,wooden connection failure and so on. Here is you can the significant deformations of wall and floor beam under, it may damaged under the he great stress caused by loads and thrusts (figure 30).

But on other hand, this kind of deformations prevent the whole timber frame system form collapse, it also reflect the timber frame system seismic-resistance seismic ability which I mentioned tioned before.

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Building construction between 1700 and 1950 Copenhagen was plagued by fire in the 17 centuries, but not because high density of timber building and lack of effective fire prevention but because they were very close together. Here you can see picture about big fire in Copenhagen 1795(figure (figure 31).Common 31) occurrence of fire accidents makes the fire prevention and safe evacuation the important research topics. There are two major fires in Copenhagen in 1728 and 1795. Here you can see picture building façade which face to street is masonry structure after fire in 1728 (figure 32).The The utterly timber construction was forbidden. The almost entire Copenhagen was enveloped in flames except the Christiania which near to harbor. After biggest fire happened in Copenhagen in 1728, 1728 the first building regulation come out, Half-timbered Half timbered with brick construction was still permitted. But the facade which faces to street must be use brick or stone material. material In Copenhagen, on the façade wall, it is quite common to see metal anchored peg. The floor joists are anchored to the external walls by the anchored peg (figure 33).

Jørn Utzon& Espansiva Danish typically wooden houses consisted of a wooden post system with classical and regularity column order which the load bearing timber structures were visible.

The woodwork was often use large glass panels between pillars or masses of wood paneling. There are some examples of single-family single homes built by Jørn Utzon, Erik

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Christian Sorensen, Knud Peter Harboe and Halldor Gunnløgssons.In Gunnløgssons.In the period, you can even saw some timber houses house which combine with Danish old bindingsværkbyggeri with Japanese timber house inspiration.

Jørn Oberg Utzon is a world famous Danish architect and designer. “The “ Espansiva system is a standardized additive system for low cost, low density rural housing, based on modules creating single storey homes. The system is based on modules of three standard sizes: Bathroom ,lobby ,toilet (3000×2016mm) Single bedroom, study ,kitchen(3000×3216mm) Living room, double bedroom(3000×5016mm) The system creates a simple series of prefabricated elements. These modules are small pavilions with a post at each corner and a standardized roof pitch at 17.5 degrees. The building envelope uses standard sized components in very lean system based on a basic module of measure of 120mm. However, it used non-standard non 3m 15 long stressed skin plywood panels on the roof.” roof.

Here you can see exploed diagram of Espansiva system(figure 34).

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T Y U N N O S – sikaspruce housing

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

CASA NOVA CASA NOVA project is first multistory timber house in Denmark since 19.century.This is kind of important break-through through point in Danish timber history.

CASA NOVA project is base on Danish modern advanced wooden house design concept .The main idea of project is to transfer principles from the industrial prefabricated concrete buildings in timber.

CASA NOVA is an attempt to build multi-storey storey buildings with wood as a building material in Hørsholm and Herning.

Herning The project is collaboration boration between: Architect: NOVA 5 Engineer: COWI Construction: Skanska Jensen Client: Lejerbo Herning The main structure of CASA NOVA is light weight timber, wrapped in plaster board because of Danish flammability requirements,, some building part are registered as concrete, for instance, elevator tower, the façade of house coved by cedar wood board and zinc. Here you can see the perspective view of CASA NOVA (figure 35).

Sortemosen

In the early 70s, Architects Halldor Gunnløgsson & Jørn Nielsen drew up a finely timber building system in Herlev.

Herlev By coupling a stack and moving the box-shaped box housing component could create variety sizes of apartment. Simultaneously, provided that the residential area with terrace and balcony. They sketch different function housing types in one and two storey. It provided for several hundred residences. It created a high manageable housing residence community. Architects Halldor Gunnløgsson & Jørn Nielsen collaboration with construction contractor firm firm Saabye& Lerche A / S

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

together development this building system. Main structure is lightweight materials coated with pressure-treated treated wood. Most of building part like facades, roof, with all the interior fitting complete and assembly in a local factory and delivered to site and mounting and establish on the foundation. Here you can see the perspective view of Sortemosen (figure 36).

10. Constructive wood protection: Fire protection by design “Wood houses don't burn like kindling - the structure normally stands for an hour and a half. Steel frame buildings collapse much quicker. Wood burns slowly and evenly and the burn rate can be precisely determined.

The burn rate for spruce is 0.66mm/min. By By appropriate dimensioning, the various fire regulations can be met without any problem. The other myth is that wood is a finite material and to use it for construction is to exhaust a natural resource. The reality is that demand creates rational husbandry. husbandry. One of the UN's environmentalist slogans is "Cut trees to save the forests". In societies where people use more wood, the forest size increases.”16 To my surprise, wood is also fire proof material, and lasts longer in fire than steel beams.

This is due to the fact that 15 percent of wood mass being water which will evaporate before actual burning. Although wood is a combustible material, when it burns, a layer of char is created which helps to protect the wood and maintain the strength and structural tructural integrity of the wood inside. This is the reason why a heavy timber system can be left exposed and still achieve a fire-resistance fire resistance rating of up to 90 minutes. On the other hand, wood is a combustible material. Normally, the amount of using wood into nto the housing construction and the risk of fire happen become direct ratio, Wood burns more readily than some other materials, making timber frame buildings somewhat more susceptible to fire damage, although this

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http://www.turkishculture.org/architecture/houses/wood http://www.turkishculture.org/architecture/houses/wood-timber-houses-278.htm?type=1

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

idea is not universally accepted. The ability of fire resistance of wood is in controversial condition. Here you can see a thoughtful quote about fire protection (figure 37).The The fire safety of a building is far more more complicated than whether the materials are combustible or noncombustible. The fact of the matter is that fire risk in a timber building is no greater than with any other type. It is wrong to claim that sheet metal frame construction provides better fire safety than wood-frame wood construction.

Typical fire protection technical Details (figure 38).

1 0 60

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2. Maximum 600 mm between each wooden column 3. The vertical distance between screw rows must not exceed 200 mm.

4. The distance of screw between the both sides of plate

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200

Typical details of 60 minutes fire protection wall system 1. Two layers of gypsum board on the both side of wall 3

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edges must not exceed 10 mm. mm 5. The joints between the plates must be filled with gypsum-based gypsum based mortar without filling tape.

Fires stop between double walls To make better sound proofing condition, therefore, to place mineral wool between floor wooden cover (figure 39). And you can even look upon it as fires stop. A fires top is a passive fire protection system of various components used to seal openings and joints in fire-resistance rated wall or floor assemblies. According to building regulation ,it have make sure the fire cannot spread form one fire division to another one by passing a cavity or separating building components .To achieve hieve this, it is necessary to make a fire stop. A fire stop is usually made of wool, but fires stop can also be made of fire resistant materials.

27

Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

11. Constructive wood protection: Preservation by design With good design and correct detailing, structural wood needs no chemical treatment to achieve a long life. Wood is resistant to heat, frost, corrosion and pollution; the only factor that needs to be controlled is moisture.

“Advisory principal rules for outdoor constructions By application of wood outdoor these th principal rules should always be followed: Water must be carried off from the construction Up-turned turned surfaces must be sloping All edges must be rounded Water traps in the construction must be avoided Open end surface must be coved and/or sealed The right side/core side) of boards and planks are turned upwards/outwards Fastening through up-turned up surfaces must be avoided Joint between structural elements should not be able to accumulate dirt.”17

Exterior wall detail Heartwood used for the exposed surfaced, topside and outward.

Sapwood is much more susceptible to fungus, it contain a lot of moisture. On the contrary, heartwood have more resistant to decay, it is a result of tylosis, it is complete “dead” wood. The heartwood have apparent resistant to many weather conditions. To sum up the above argument, it is better place heartwood outward to against weather and bacterial and fungal attack (figure 40).

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http://www.wbdg.org/design/env_fenestration_doors.php

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Moisture is one of the main causes of damage to the building envelope. Rain infiltration past the cladding and into the back wall can result in mould and row growth. The water running down on the sheathing or wood may spread easy spread in the horizontal direction by surface tension effects and driving rain load .Therefore, it is better to place the fiber direction vertical when placing the outer wood cladding or panel (figure 41).

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Distance to the ground Wood is more easy attack form fungi and rot if it in touch with ground. It must ensure a suitable distance to ground. The purpose of waterproof design cladding is to gives long service life and low maintenance costs. Ensure that the cladding and protected from indirect wetting, as a result of splashing off the ground, by stopping any wood cladding minimum mum 200mm above ground level(figure 42).By By the way, to avoid infestation by insects any openings at the top or bottom of close jointed boards should be protected by an insect mesh.

Drip nose and water flashing Drip nose can take off water from timber façade faça and prevent water from being sucked into the wood, for instance lower edge of vertical and horizontal board.

Because air pressure differentials caused by wind action can drive water in any direction, including uphill.

Water can be driven to penetrate a building by any of a number of forces. Even the momentum of a falling raindrop is sufficient to drive the drop and its spatter spat deep into an opening. Flashing is a metal or plastic strip attached to the outside of the head or side jambs to provide a weather barrier, preventing leakage between the frame and the wall. wall

29

Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

On the bottom of window and door, the flashing water board must place with inclination with minimum 2%. Flashing at exterior doors is similar to flashing at windows for head and side jambs. Flashings should be carefully designed to keep water out; even in atrocious conditions .The principle is simple: create a gap between the back of the cladding and the timber framing by fixing a timber batten .It It is a cheap and efficient means of accommodating a small amount of water that might periodically penetrate behind the cladding. Such small amounts of water are able to drain ain out at the bottom of the wall(figure 43).

Eaves Overhangs and Eaves give good and effective protection of the cladding, windows and doors, etc. from rain and sun.

Exterior wooden structure need maximum be covered so they can be protected from rain and precipitation (figure 44).A A larger eaves course, a larger effect. The eaves contribution has shadow effect on the upper wooden w facades, it give a slowerpatina slower on the surface of façade. It could mean a color difference between the façade upper and lower part. Eaves boards are used on the verge of gables where the coverings of roof extended over the wall. On the facade, it can be developed kind of eaves system to make reduction re of rain infiltration past the cladding (figure 45).

Foundation detail The top side of concrete must have a slope to carry the water away if the timber post is embedded in concrete (figure 46). Also the concrete surface must be having 200mm below the ground least.”By concrete foundations including embedded anchors distance must be kept between wood and concrete, to prevent rising soil moisture (capillary capillary rise) and to promote drying through the end grain of the post.”

Timber components assembly

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Timber matched board may have a tongue, groove or other profiles to allow assembled each other. But it must given minimum 5mm distance when vertical assembled board’s .This way can ensure that the timber components remain well ventilated ed and avoid fungus happened (figure 47).

12. Other Timber constructi0n method can be found in Denmark In Denmark, there are many timber frame structure like churches, home and barns.

Timber framing, as everyone knows, is a traditional style of construction. Along with development of the timber housing technology, there are some new timbers structures building come out in Denmark. The flexibility of timber construction methods makes it easier to vary a building’s orientation on site, its floor plan, the number of rooms, the interior design and the overall appearance appearance. Except the timber-frame construction which mentioned before, otherr timber structure can categorized into four methods: Platform framing This construction method is very based on an artisanal establish on site, always come along with (logistics, weather, etc).The superiority of Platform framing is it’s flexible because it can response to a lot diverse design specification. The framed structure sits atop a concrete (most common) or treated wood foundation. A sill plate is anchored,, usually with 'J' bolts to the foundation wall.

This form of construction is straight forward and economic. This construction can be done by simple nailed and screwed connections. “This is floor-by-floor floor floor process traditionally used for building no higher than three stories, and is the most common method of wood construction in North American today, accounting for almost 95 percent of wood construction.”18There are two advantages: first one is it can use standardized pieces of timber, which less expensive, and easier to handle. Second advantage is

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Constructing architecture materials processes structures a hand book P96

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

constructed one floor at a time, allowing that floor which you just finish as platform for constructed next floor (figure 48).

Balloon framing “In the 1830s in Chicago, a new method of building called balloon framing evolved, which requires less skill to construct and less time to build than timber framing. It also utilized smaller trees that are more common. With the quickly growing population and the need faster construction, balloon framing gained in popularity. It has been argued that this method also evolved due to the easy construction methods for barns and outbuildings.”19Balloon framing is a method of wood construction used so popular in Scandinavia. The timber stud is the equivalent of Balloon framing; it was quite widespread in North American.

Balloon farming is variety version of platform framing. Platform form framing make the timber floor completely finished before start build next storey, but the balloon framing is build from foundation foundatio to raise height continuous, using wood component that continue through two or more stories in height. That is main different between Platform framing and Balloon framing. Balloon framing provides better stability and less consumption of wood. This system also has a high degree of design freedom regarding the plan layout, positioning of opening and space. But this his farming system has some drawback like the fire can spread rapidly from bottom to upper floors, increseasing the risk of smoke flues happened. So somehow, this method is often found in little bit old structures and is not very popular used today (figure 49).

Plane Construction In Denmark, concrete is one of popular engineering structural materials use for wall slab and floor in last 40 years. This technology is extremely thorough and experience 19

”Materials for design” by Vitoria Ballard Bell

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

accrued from the production of thousands of public prefabricated housing units.

During the same period, the timber industry developed industrially to produce flat wooden elements, so-called called "stress-skin" "stress skin" elements, based on a wooden frame with plywood.The elements lements used primarily for roofing as replacement for traditional timber structures with odd, battens, underlay and finished roofing. The advantage of using this building system is make good ventilation environment under roof, minimizing timber rotting problems pro happen.

Elements can be supplied with varying degree and sizes completion form raw material that get the cladding finished affixed. Make a big reduction of site operation period compare to the tradition timber building system.

The latest development nt in Panel construction is leading to a reversal of the principle of platform frame construction. The loading bearing element is now a slab, no longer a linear member. This slab must exhibit high strength and rigidity in order to achieve a structural platee action. Openings can be cut almost at random. Insulations is placed between the ribs. The traditional grid or spacing of load bearing elements is no longer necessary(figure 50 0).

Solid wood wall system The use of timber systems call "massivholz-systemer" is becoming increasingly popular, which builds by solid timber wall and floors element. This method provides an excellent fire proof and sound proof conditions, but the price to build this kind of house is quite expensive (figure 51).

13. Timber building is our future!

Wood is one of best building material available to protect our environment. Wood is a high-performance high material, high in density low in weight, with excellent load-bearing load and thermal properties, and the availability of a wide range

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

of timbers, each with its own characteristics, means wood can be suitable for most special requirements. This is a curved roof made of wooden hexagonal units supported by a central metallic spire and four conical pillars. The large surface area of this signature ure roof element covers a collection of interior spaces where three galleries unite (figure 52)..

Thermal protection The thermal conductivity of softwood is around 0,13W/mK 0.20 W/mk for hardwood, by compares with figures of 0.44 W/mk for clay bricks and 1.80 W/mk for concrete.

For the same thickness, wood is a better thermal insulator than other structural building material; 15 times better than concrete, 400 times better than steel and 1770 times better than aluminum. A wooden house makes it possible to reduce the operational cost of the building with about 25-35 35 %, due to its thermal efficiency and also to the construction model avoiding thermal bridge.

Durable: According ccording to historical records, yet et it is durable as evidenced by the over 1000 year old stave ve churches in Norway, the over 1500 year old temple complexes in Japan and China and artifacts from Egyptian tombs that are over 3500 years old. But who wants to build to last for such an eternity? Nevertheless, the fact is that wood has an almost unlimited ed life providing of course that is has been properly dried and is protected from prolonged exposure to moisture. Timber keeps as long as it is not attacked by mould, insects and fire.

Renewable Timber resources are renewable and recyclable; Wood is produced by solar energy.

A tree takes up water and mineral salts from the soil and carbon dioxide from the air.

It processes these by photosynthesis. It is a “natural”” material, it is renewable and biodegradable. In Denmark, comprehensive timber recycling recycling is developing now. The renewal of timber windows has become significant in the industry; the old oak beams are split up after the central core has been removed for use in floor boards or windows.

Sustainable Trees absorb carbon dioxide (CO2) and emit oxygen. Harvested trees used in wood construction continue to store CO2 throughout their product lifelife around1 tone per

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

cubic meter- while sustainable forest practices mean they are emplaced by even more trees. “Log Homes and Timber Frame Homes may have the lowest carbon footprint of any other type of construction. Carbon dioxide is the main greenhouse gas released into the atmosphere and major contributor to global warming. The reduction of greenhouse gases was achieved by replacing materials high energy, high CO2 production values, such as steel and concrete, with solid wood. The report states that the production of steel and concrete materials accounts for 10% of the total global emissions of greenhouse gases. These materials have a high CO2 output created during the extraction of raw materials, refining, processing and manufacturing of the finished product .The steel wall system generated 33% more greenhouses gases than wood and the concrete wall generated 80% more greenhouse gases than wood. Properties of wood In Denmark, to assures timber natural resources in a constant sitatuation,to reinforce Danish commitment to the environment, they attained chain of custody PEFC certification.PEFC Council endorsed the Danish Danish scheme in October 2002 to ensure timber comes from sustainable forests.

Healthy Wood creates naturally healthy living conditions. It is easy to keep clean, helps maintain an optimum humidity balance, helps a room warm up more quickly, and keeps condensation nsation to a minimum 14. Conclusion Today, when architects and engineers design landmark, buildings like bridges or government offices, schools or factories, they look to timber to express a contemporary beauty which is nonetheless rooted in nature and a respect for the environment. Those who promote the use of wood hope their efforts will encourage people not just to cherish old buildings but to use use the knowledge those buildings encapsulate to create new traditions. Throughout Danish building history, and certainly over the past millennium, Danish timber building move on with his modest step with move gaited on a loose lead at a moderately fast trot, exhibiting good reach in the forequarters and good drive in the hindquarters.

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

14. Bibliography Books: Constructing architecture materials processes structures a hand book book Timber in Construction Edited by John Sunley and Barbara Bedding Trehus Edited by Knut lavar Edvardsen og Trond Ramstad Material for design Edited by Scott Tennent WOOD CULTURE AND TIMBER HOUSES Edit by Andrew Finkel The Ecology of Building materials by Bjørn Berge Publish: Timber-Frame Frame Buildings in Scandinavia: High Deformation Prevent the System from Collapse Edited by Pietro Copani Fire Safety in Residential Buildings The befits of using wood Wood Edited by Waitakere City Council, The art of Timber framing T Y U N N O S – sikaspruce housing Visits: National Open Air Museum of Urban History and Culture (Den gamle by) National Museum in Copenhagen Illustrations: Figure 1: A cross section of a tree trunk Figure2: Two basic categories of wood Figure 3: process of “where does the timber come from” Figure4: dry-rot rot fungus attack the timber Figure 5:: Replace the rotten timber frame

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Figure6: Where timber is in connection with brick walls there is risk for fungus.

Figure 7: Comparison of fungi found in publications publications from the Nordic countries.

Figure8: wood boring insect life cycle Figure 9: Furniture Beetle Figure10: Longhorn Beetle Figure 11: Death watch Beetle Figure12: Forbidden City Figure 13: Yakushi-ji Figure14: 6-storey storey timber hostel in turkey Figure15: The first stave churches in Norway Figure 16: Garden House Figure17: Commercial and residence building Figure18: Mountain villa Figure19: Hotel Figure20: Farm Figure21: Pavilion Figure22: luxury residential Figure23: Cabin Figure24: Palisadevek, Bulhsuet, Stavrek, and BindigsvĂŚrk from top to bottom Figure25: Timber-frame frame construction Figure26: suspended floor between normal storeys and over basement Figure27: Den gamle by Figure28: wooden carved on the timber frame

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Figure29: massive deformation Figure30: significant deformations of wall and floor beam under Figure31: big fire in Copenhagen in 1795 Figure32: building façade which face to street is masonry structure after fire fi in 1728 Figure33: anchored peg Figure34: Espansiva system Figure35: CASA NOVA Figure36: Sortemosen Figure37: quote about fire protection Figure38: Typical fire protection technical Details Figure39: Fires stop between double walls Figure40: Heartwood used for the exposed surfaced, topside and outward Figure41: fiber direction vertical Figure42: Distance to the ground Figure43: Drip nose and water flashing Figure44: Eaves Figure45: eaves system Figure46: Foundation detail Figure47: Timber components assembly Figure48: Platform framing Figure49: Balloon framing Figure50: Plane Construction

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Danish Timber Building

Yi Lin

KEA - Københavns Erhvervsakademi

Figure51: Solid wood wall system Figure52: huge roof element WebPages: http://wapedia.mobi/en/Timber_framing http://www.owdman.co.uk/joinery/sust.html http://www.diydata.com/problem/timberrot/timberrot.php http://wapedia.mobi/en/K%C3%B8ge http://www.turkishculture.org/architecture/houses/wood-timber-houses http://www.turkishculture.org/architecture/houses/wood houses-278.htm?t ype=1 http://www.wbdg.org/design/env_fenestration_doors.php

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