Ass.Prof. Manja Kitek Kuzman University of Ljubljana, Department of Wood Science and Technology

Prof. Dick Sandberg Luleå University of Technology

March,10 2016

Comparison of Timber-House Technologies in Slovenia and in Sweden SWST International Conference , Curitiba | Forest Resource and Products: Moving Toward a Sustainable Future

Wood Architecture in Slovenia and Sweeden In the building traditions of other countries it may be fine stones and hand-made tiles - in Slovenia and Sweeden, that status is given to wood. The knowledge about this age-old building material is actively preserved and applied with a contemporary twist. Different approaches, but similar use of building techniques with wood which is today described as the “exponent and guarantee (material) of building that looks to the future”.

Introduction - Slovenian and Swedish wood

Slovenia and Sweden

many similarities in terms of the importance of forests for their society Slovenia’s and Sweden's forests in numbers year 2014 Slovenia Surface area of productive/total forested land 1.2 total forested land (million hectare) Forested area of country (%) 58.4 Number of naturally 71 occurring tree species Total standing volume on 340 productive forest land 3 (million m standing volume*) Annual forest increment in all 8.4 3 land use classes (million m standing volume*) Annual cut 5.75 3 (million m standing volume*) Hardwoods (%) 53 Softwoods (%) 47 The most important wood Beech 32%, spruce 32% species oak 7%, fir 7% *stem volume over bark from stump to tip

Slovenia Pokljuka

Sweden 22.4/28.2 57.0

3.016

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91.5 21 79 Scots pine 39%, Norway spruce 42%, birch 12%

Consumption of sawn wood and wood based panels in selected countries per capita 2006-2008 (Forest Products Statistics 2004–2008, 2009)

Sweden Västerbotten in north Sweden 3

Vernicular architecture

Tradition - a proof of the craftsmanship of woodmasters Diferent traditiona typs of wooden houses

Paying attention to the tradition of construction in the planning of the new, improved and modern is the only path towards preserving a nation’s culture and the features of the cultural landscape.

⌂ Farmstead in Gorenjska, SI

Stave church Grandhult church, Småland, S

⌂

⌂ Wooden shipard house, Velika planina, SI Traditional l swedish house | falun red, S

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⌂

Vernicular architecture

Tradition - a proof of the craftsmanship of woodmasters Diferent traditiona typs of wooden houses

slovenian landscape

Architecture belongs to culture, not to civilization. Alvar Aalto

Slopping walled barn in Svensbynroom for hay.

⌂ Wooden hayreck, Studor, SI

⌂ The oldest wooden house in Sweden, about 1230.

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Building Techniques in Sweden and Slovenia

Frame-Panel construction Dominant methods of timber construction

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4 www.archdaily.com/498686/molle-by-the-sea-elding-oscarson

timber gird insulation material inserted between the studs

6 realisation

vertical stud

Mölle by the sea, Mölle, Sweden, 2013 sheating board staples

Nominated for Swedish Timber Prize “Träpriset, 2016

faced inside with gypsum- or woodbased panel materials

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Building Techniques in Sweden and Slovenia

Solid Timber Construction (SCT)

http://clta.jp/wp-content/uploads/2013/10/20131024_SCHICKHOFER

Innovation based on tradition

Source: Prof. G. Schickhofer | Institute of Timber Engineering and Wood Technology| Graz University of Technology: CLT Forum 2013 in Tokyo

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Building Techniques in Sweden and Slovenia

CLT for supporting framework Solid laminated wood panels are: ‘... the concrete of the 21st century.’ ⌂ Wall unit on its way at Hyttkammaren in Falun

⌂

Michael Green Architect (2012)

Assembly of floor structures at Limnologen in Växjö

Gerhard Schickhofer, Institute of Timber Engineering and Wood Technology, TU Graz

Thistleton's Murray Grove, London

⌂

⌂ The wooden form of Waugh

Global production of CLT 1995-2015: 35 production sites worldwide, 95% of production volume in Central Europe : Austria 65%, Germany 26%, Switzerland 6% 1 Mio. m3 of productiom potential worldwide can be expected at latest of 2015

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Building Techniques in Sweden and Slovenia

Vila Eder- Hederus

www.generalarchitecture.se/projects/villa-eder-hederus/

Nominated for Swedish Timber price 2016

Nominated for: 12th Swedish Timber Prize, in Sweden entitled “Träpriset” 2016

Lage | Kummelnas, Nacka Ansvariga Arkitekter

Building Techniques in Sweden and Slovenia

Wood – Frame Construction Vila Emils Backe, Smedstrop, Trosa, Sweden, 2014 A system of columns and beams, where glulam is used to a large extent for the load-bearing structure.

Läge: Smedstorp, Trosa Typ av byggnad: Villa Byggherre: Ekologiska byggvaruhuset genom Erik Hedenstedt Ansvarig arkitekt: Arkitektstudio Widjedal Racki Medverkande arkitekter: Håkan Widjedal, Natasha Racki Byggnadsentreprenör: Hedenstedt Konstruktör: Limträteknik i Falun Byggår: 2014

http://www.emilsbacke.se/

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Building Techniques in Sweden and Slovenia

The dominant frame system for single-family timber houses Sweden timber grid

⌂ Several modern timber-house Façade covering: can be brick, plaster or solid timber.

companies manufacture building elements, such as roof trusses, joist floors and wall units, themselves.

insulation

vertical studs

gypsum, wood-

based panel mat

⌂ The method of producing a house or parts of a house in an industrial production environment is termed “prefabrication,” and this is the dominant method of building single-family timber houses in Sweden.

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Building Techniques in Sweden and Slovenia

The dominant frame system for single-family houses Sweden Sandgrind, Kungsängen Byggår: 2008 Beställare: Skanska Fakta: 6 hus. Leverans: Modul. Övrigt: Ett projekt med ekologiska förtecken i ett enastående vackert landskap med utsikt över Mälaren.

Single-family timber housing businesses employ one of two strategies for the final stage: 1. manufacturing plane elements in the plant and transporting them to the site for final assembly or 2. assembling the plane elements in the factory and then shipping them as complete volumes to the final building site.

Fickuret, Örby Byggår: 2012 Beställare: Arcona AB Fakta: 17 radhus, 2 hustyper på 120 m2 respektive 135 m2. Leverans: Planelement, stomleverans inkl montage ovan färdig grund. Övrigt: Öppen planlösning krävde avancerad projektering, produktionsteknik och montage. Färdigt resultat är ett modernt boende med uttryck.

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Building Techniques in Sweden and Slovenia

Modern timber-house companies Sweden

⌂ On site assamble: Martinsons’ dwelling house with a frame of CLT can be delivered including complete electricity and HVAC installations.

⌂ A few manufacturers use CLT systems. The most appealing reason for using the CLT system is that the wall units and joist floors have a high load-bearing capacity and stiffness.

During the manufacture of the unit, the shapes are trimmed, openings are left for windows, doors, etc., and the thickness is levelled if necessary. Prefabricated CLT panels are delivered directly to the construction site. The producers of houses with CLT systems do not have their origins in the tradition and company culture associated with single-family timber houses. 17

Building Techniques in Sweden and Slovenia

Construction on site The oldest method of construction

⌂ A wood framed construction

⌂ CLT panels delivered to the construction site The method requires a great deal of organization and planning on the building site. Risks associated with damage to materials and prefabricated structural components, due to moisture must be overcome .

Linnaeus University is ˝Hus N˝ Location | Växjö Type of building | building for education Year of construction | 2011 Architect | Mats White Main contractor | Videum AB Construction company | Södra Construction description | visible glue-laminate framework Area | 6.320 m2 Fasad | modified wood fasade Client | Linnaeus University ! European Green Building

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Building Techniques in Sweden and Slovenia

Construction on site The oldest method of construction

⌂

With the on-site building technique, wall components are generally assembled resting on joists or the ground and then erected manually.

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Building Techniques in Sweden and Slovenia

Off site prefabrication The trend toward a higher degree of prefabrication Examples of off-site prefabrication: a building with prefabricated panels or modules is faster, less weather dependent and provides better control over costs.

www.trabyggnadskansliet.se Prefabricated modules for single family house are assembled on-site.

www.marles.com/hise/en

Prefabricated window is assembled on-site

⌂ Far more common today is the prefabrication of various components: off-site building, which is regarded and accepted as a high-qualitative and less expensive production method.

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Modul system

Modular system Prefabricated components of wood

princip

Camp Wildalpen, Camp Passail Vir:“Holzbox” Foto: W. Luttenberger Working with modular systems is a huge help, since it is difficult to design traditionally and then translate the design to an industrial context.

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Modul system - Sweeden

Spatial cells Residential appartments Skagersvägen Stockholm

Long facade in innovative modules

To achieve the unbroken vertical lines that run up the facade, the architect designed the cladding piece by piece.

Type of building | residential, 33 appartments Location | Skagersvägen 22-26, Årsta, Stockholm Building year | december 2013 Architect | OWC Björn Ahrenby, Joan Anguita, Anna Montagut Construction company | Moelven (Moelven’s modular system) www.martinsons.se Construction description | 112 box units built around a spruce frame - prefabricated modules Energy performance | energy class: low-energy Area | 4817 m2 Number of floors | 3 floors Fasad | untreated ceder wood panel Owner of the building | Åke Sundvall Projekt AB Price | The Nominated for the 2016 Swedish Timber Price

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Modul system - Sweeden

Ekorrn District Skellefteå The advantages of industrial construction in wood: less time on the building site, less transport, less disruption for neighbours, good cost control and no drying time compared with that for in situ concrete. Residential building Location | Södra Lasarettsvägen 10, Skellefteå Construction type | residential block, 54 apartments Building year | 2009 Architect | Magnus Silfverhielm, architect at AIX Arkitekter Construction company | Plusshus, www.setragroup.com Construction | Setra’s Trälyftet building system with Glulam (modular system) Energy performance: energy class | low-energy, operational energy use: 25 kWh/(m2a) Number of floors | 5 storey Modified wood used in building | no Fasad | untreated ceder wood panel Owner of the building | Brf Ekorren

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Sweeden – modul system

Additional stories or extensions to roof Timber - great potential for modernizing older buildings

Effective additional floors of CLT Martinsons’ construction system in glulam and CLT offers unique possibilities for additional floors to existing buildings. Thanks to the construction parts’ strength compared to their low weight, additional floors can be made without expensive and time-consuming frame reinforcements which are often required with the use of other materials. Additional floors on existing buildings

I believe that the material doesn’t need to be strong to be used to build a strong structure. The strength of the structure has nothing to do with strength of the material. – Shigeru Ban

Timber offers great potential for changing and modernizing existing, older buildings which are often constructed from concrete, mainly through additional stories or extensions to roofs. 25

Sweeden – modul system

Additional stories or extensions to roof Timber - great potential for modernizing older buildings

UMEÅ Timber offers great potential for changing and modernizing existing, older buildings which are often constructed from concrete, mainly through additional stories or extensions to roofs. The simplest method is to fit the old building with a new roof designed so that a number of apartments can be built into the attic space.

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Renovation

Fabricated large-scale façade wooden moduls Thermal modernisation

Residential area Dieselweg 4 _Graz, Austria

Key technologies • Solar façade • Pre-fabrication of facade modules • Energy concept based on renewable energy sources • New heating- and DHW supply system installed between the façade and existing wall • Decentralized ventilation systems with heat recovery • Control and remote maintenance via internet

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Renovation

Fabricated large-scale façade wooden moduls Thermal modernisation

Winter

Summer 29

Renovation

Fabricated large-scale façade wooden moduls Thermal modernisation – concept of prefabrication Assembly of the lowest module

Sequence of assembly of the façade modules [Kulmer Bau]. First module is the lowest one; it is mounted on steel-bearing angles, which are fixed on the plinth. All other modules rest on the previous one. Therefore all joints are horizontally designed.

Sequence of prefabrication procedure in the fabrication hall [Gap-Solution GmbH]

Module dimension: 12 x 3 m Dimension of modules is fixed by the line of the intermediate floor and the window lintel. 30

Present stage of multy-storey buildings

Multy-storey Buildings

→ 1995-2005 3 - 5 storey buildings in several european countries, i.e. 4 - 5 storey buildings in Sweden (Växjö, Uppfinnar) → 2008 → 2009 → 2011 → 2012 → 2013 → 2013

8 - storey condominiums in Växjö, Sweden 9 - storey condominiums in London, UK 7 - storey multy-family house in Berlin, Germany 8 - storey condominium in Bad Aibing, Germany 9 - storey apartment building, Milano, Italy 10 - storey building in Melbourne, Australia

→ 2020 ?? → 2025 ??

30 - storey building proposed for Canada 34 - storey building proposed for Stockholm, Sweden

34-storey Wooden Skyscraper is presented by architect CF Møller

Wooden Sky Scrapers

Extensive research has shown that material-neutral building regulations are preferable and, for over a decade, function-based regulations have been common in many countries. 31

Multy-storey Buildings: Limnologen

Multy-storey Buildings

www.forum-holzbau.ch/pdf/ihf09_Serrano.pdf

Växjö - Limnologen in Växjö consists of four 8-storey high residential buildings

Acoustics and vibrations

Connection between interior wall and floor (Martinsons)

Residential building Location | Växjö Construction type | residential blocks, 134 apartments Building year | 2008 Architect | Arkitektbolaget Kronoberg Total area | 10.700 m2 Total building time| Approx 17 months per stage One storey erection time | 10 days Construction | Midroc Property Development with Midroc Projects AB as main contractorr Structural engineers | Martinons Byggsystem Energy performance: energy class | low-energy Number of floors | 4 8-storey buildings Type of ownership| Tenant-ownership

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Multy-storey Buildings

Multi-residence building, Älvsbacka Strand

Skellefteå - 6-storey high residential buildings

Factors of increase: -a lower cost of wood-building -advantages of using wood in industrial building, -growing environmental awareness, -a renewable material, -reduces CO2 emissions, -timber is harvested in forests where sustainable forestry, with replanting and management plans, is practiced.

Residential building Location | Skellefteå Construction type | residential, 3 houses Year of construction | 2008, 2009, 2010 Architect | White arkitekte Construction company | Martinsons www.martinsons.se Construction description | solid timber construction CLT Energy performance | energy class: low-energy Number of floors | 6 Modified wood used in building | no Fasad | timber panel facades Owner | Brf Älvsbacka Strand

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Multy-storey Buildings

Portvakten residential building

Växjö - two 8-storey houses with wooden framework and passive house technology

⌂ Weather protection. All assembly work takes place under protection against weather.

⌂ Passive house installations. Draft of installation system.

Residential building Location | Växjö Type of building| residential building, 64 apartments Year of construction | 2009 Architect | BSV Arkitekter Construction company | Martinsons, www.martinsons.se Construction description | glue laminate system solid wood frame Project | project »Energy efficient Växjö« Area | 64 apartments in 2 buildings Energy performance: energy class: passive house, operational energy use: 15 kWh/(m2a) Number of floors | 8 floors www.martinsons.se

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Multy-storey Buildings

Car park, Ekorren District Skellefteå – Sweden's first timber framed multi-storey car park

⌂ The car park has six floors, of which two are underground.

⌂ The glulam and CLT building sections have created aesthetic opportunities, where the visible wood elements contribute to a natural wood feeling.

Multy-storey car park Location | Nygatan 24-28, Skellefteå Construction type | infrastructure, car park Building year | 2009 Architect | Magnus Silfverhielm, architect at AIX Arkitekter Construction company | Martinsons, www.martinsons.se Construction description | Martinsons’ concept is based on a column and beam frame in glulam combined with a bearing cassette joist made of CLT Area | 700 m2 Number of floors | 4 floors Fasad | ribbed facade panels Owner of the building | Fastighets AB Polaris

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Multy-storey Buildings

Multy-storey Buildings The next generation of wood-based construction

The ideal project does not exist, each time there is the opportunity to realize an approximation. Paulo Mendes da Rocha

The allowable numbers of storeys in Slovenia and Sweden depending on whether or not a sprinkler system is installed Building properties Sprinkler Load-bearing structure YES Load-bearing structure NO Wooden façade claddings YES Wooden façade claddings NO Wall and ceiling linings in flats NO (surface linings of ordinary wood) Wall and ceiling linings of NO untreated wood in escape routes Wall and ceiling linings of fireNO retardant treated wood in flats Wall and ceiling linings of fireNO retardant treated wood in escape routes

Sweden1) 5 5 5 ≥1 ≥1

Slovenia2) 5 3 max. 63) max. 33) --4)

≥1

--4)

≥5

--4)

≥5

--4)

1)

Mahapatra and Gustavsson (2009); 2) RS, Ministry of the Environment and Spatial Planning (2010); 3) See Table 8 and 4) see Table 5 in reference 2) RS, Ministry of Environment and Spatial Planning (2010)

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Surprise is key in all art. Oscar Niemeyer

Architecture begins where engineering ends. Walter Gropius

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Attitudes towards wood construction

Promotion use of wood

The next generation of wood-based construction Architecture is invention. Oscar Niemeyer

→ different perception, → Sweden: wide range of programs to promote multi-storey wooden buildings; Swedish National Wood Construction Strategy and its Continuing Training Programm, Swedish Timber Prize,.... → Slovenia: Green Public Procurement (GPP): The regulation of GPP aims to reduce the negative environmental impact.

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Promotion use of wood

Promotion of Energy-efficient buildings

Low-energy building, Nearly Zero energy building, Passive house, Active house,...

Passive house  Passive Houses require less than 15 kWh/(m²yr) for heating or cooling . (relating to the living space).  The heating/cooling load is limited to a maximum of 10 W/m2.  Primary energy use may not exceed 120 kWh/(m²a).  Passive Houses must be airtight with air change rates being limited to n50 = 0.6/h.  In warmer climates and/or during summer months, excessive temperatures may not occur more than 10 % of the time. RENEWABLE ENERGY SOURCES

19th Century

20th Century

21th Century

AIMS reduction of energy demand and GHG emissions

GIVEN CONDITIONS climate locattion BUILDING COMPONENTS PASSIVE DESIGN STRATEGIES

OPERATION / USE ACTIVE SYSTEMS

Basic principles of eenergy-efficient design

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Conclusion

Promotion use of wood

We see opportunities for further development and future trends in:

→ High prefabrication, → Partnership and increased responsibilities for planning and construction, → Improved and systematic feedback of experiences, → Demonstration projects are vital, → Team coopertion

As an architect, you design for the present, with an awareness of the past, for a future which is essentially unknown. Norman Foster Skellefteå, 17.2.2015

Linear time is an invention of the West, time is not linear - it is marvellous tangle in which, at any moment, ends can be chosen and solutions invented, without beginning or end. Lina Bo Bardi, in Marcelo Carvalho (ed) – Lina Bo Bardi Bardi Institute, São Paulo, 1993 Substances. The Architecture of Lina Bo Bardi

Thank you! Welcome in Slovenia

SWST 2016

Ass. Prof. Dr. Manja K.Kuzman, architect Department of Wood Science and Technology University of Ljubljana, Slovenia [email protected]

„Brazil was, is, and will be in fashion.” Gilberto Gil