Swedish SFIF Building With Wood

7/27/2019 Swedish SFIF Building With Wood

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Building with woodModern Solutions for Wood Construction

A exible engineering materialUsing wood in building structures isnothing new. Throughout the ages, inthose places where orests grow, woodhas commonly been used as a building

material. The international trade withtimber also means that countries withlimited availability o orest resourcescan nowadays have access to wood orbuilding purposes, wood that comes

rom sustainable and certi ed orestry.Building with wood is energy-e cient,cost-e ective and environmentally

riendly.Wood has many bene ts as a building

material when compared with other ma-

terials. Above all it has a low weight inrelation to its strength and load bearingcapacity. The material is exible andcan be worked and crafed with simple

tools. On top o this, it is a renewable,biological material that is part o thenatural eco cycle. In this way, the use owood makes a vital contribution to thereduction o the earths emissions ocarbon dioxide.

Wood constructions also have sig-ni cant advantages in severe seismiczones.

Cooperhill Mountain Lodge in re

Rydebck in Helsingborg

Limnologen in Vxj


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Building on-siteBuilding methods vary. The oldestmethod is to construct the building onsite. The building materials are reigh-ted to the building site and the variouselements walls, joists etc. are puttogether on site and then erected. The

method requires a great deal o orga-nization and planning on the buildingsite. Risks associated with damage tomaterials and pre abricated structuralcomponents, due to moisture must beovercome. O necessity, on site con-struction tends to take a long time.

With the on-site building technique,wall components are generally assem-bled resting on the joists or the ground

and then erected manually.

Building techniquesSeveral common techniques are availa-ble or constructing buildings with sup-porting rameworks made o wood. Oneway is to use structural wood membersto orm a rame which is covered bystructural wood panels. Foundations aregenerally concrete. This simple buildingtechnology is ofen used in the con-struction o single- amily houses butalso in the construction o multi-storeybuildings. Another technique is to usesolid timber or the supporting rame-

work. Cross-laminated timber is madeo timber wich is glued together. It isused to build walls and joists. The wallsmay need to be insulated to give thebuilding a high level o energy e ciency.The technique is well suited to the con-struction o multi-storey buildings.

Yet another technique is the systemo columns and beams. In this caseglue-laminated timber in di erent orms

is used to a large extent or the load-bearing construction.

All these ramework systems satis ymodern criteria or re sa ety, noisepollution and energy e ciency. Specialconsideration to these unctional criteriamust be given in the case o multi-storey buildings. Well-tested technicalsolutions are now widely available.

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Cross laminated timber.

A wood ramed construction.

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Examples o outer walls with panelsheeting and timber studs

01. Finishing render 02. Render with rein orcement net 03. Insulation 04. Gypsum wallboard 05. Insu-lation 06. Vertical stud 07. Plastic oil 08. Insula-tion 09. Horizontal stud 10. Gypsum wallboard

01. Render 02. Fiber cement board 03. Nailing batten 04. Gypsum wallboard 05. Insulation06. Vertical stud 07. Plastic oil 08. Insulation09. Horizontal stud 10. Gypsum wallboard


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Single amily housesWood rame is the most requentlyused system or single amily housesin Sweden. It is also common or single

amily houses to be built using pre ab-ricated components.

The construction method allows majorvariations in the design o the houses,

con orming to national and local buildingtraditions while permitting architec-tural innovation. To a large extent thedesign determines the cost o thebuilding, whether it is a luxury home ora cost-e ective single amily house at aprice the average amily can a ord. The

requirements or re sa ety and noisepollution are usually lower or single

amily houses than or multi-storey buil-dings. However it is harder to satis y thedemands or low energy consumption ina single amily house.

stra Kvarnskogen in Stockholm.


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Multi-storey buildingsIn many countries national building re-gulations have tended to restrict the use

o timber rames or the construction omulti-storey buildings. The reason manycountries have re rained rom using

ammable materials is uncertainty aboutres in the buildings.However, extensive research and

development has shown that material-neutral building regulations are pre e-rable and or over a decade unction-based regulations have been commonin many countries. Wood burns, but in

a controlled manner. It is possible toestimate how much o the cross sectionwill remain una ected by the re aferone hour o burning and choose material

dimensions so that the una ected parto the cross section has the ability to

bear the required load. Steel, on theother hand, loses its entire load-bearingcapacity at the temperatures that occurduring a ully developed re. Non- am-mable sur ace materials and/or sprink-lers can be used to ensure sa ety duringthe early stages o a re.

Modern building regulations havecontributed to the increase in construc-tion o multi-storey timber buildings o

between three and eight storeys. Thedramatic increase can be attributed toseveral important actors. One actoris the lower cost o building compared

Ekorren in Skelle e.Rcksta in Stockholm.

Wood burns in a controlled manner and a cross section can be chosen so that the beam can bear the required load.Photo by SP Trtek, Sweden, or the technical guideline Fire sa ety in timber buildings.

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Wood constructions have signi cantadvantages in severe seismic zones.

A survey was conducted ollowing the

tragic earthquake in China, May 2008.The evidence showed that wood ramebuildings had outper ormed buildingsconstructed rom other materials. Theysu ered only minor damage, while manybrick in ll walls collapsed and concretebuildings su ered severe damage.

This has also been proven by tests;tests show multi-storey hybrid struc-tures can survive the most severeearthquakes 1. A ull-scale, seven-storeymixed use condominium tower (sixwood rame stories above a one-storeysteel structure) was tested in Kobe,Japan.

This was the largest ull-scale earth-quake test in the world. The building wassubjected to a quake that was 180 percent o the Northridge record at CanogaPark. It su ered no signi cant damage,

demonstrating that wood buildings cansurvive even the strongest earthquakes.

There are solutions reducing the impactrom earthquakes. Shock absorbing is

the latest technology or earthquakeprotection o bridges and building con-structions. The gure shows an exampleo an anti-vibration device a panel

with an anti-vibrationunit developed inJapan, or absorbingseismic energy inwooden constructions.When the orce roman earthquake hits theconstruction, the en-ergy is trans ormed viathe panel to the shock

absorber.

Seismic per ormance

with construction using other materials.Timber has shown itsel to be the bestmaterial or use with industrial buildingmethods, enabling costs to be reduced.

Another actor is growing environ-mental awareness, where the choiceis motivated by the act that timber isa renewable material and that its usereduces CO 2 emissions, provided thatthe timber is harvested in orests wheresustainable orestry, with replanting andmanagement plans, is practiced.

Another actor is the ability to buildon sites where heavier buildings (e.g.those made o concrete) would demand

extensive and expensive pile ounda-tions. Lighter timber constructions, withsimpler and inexpensive oundations canmake di cult sites easible.

The design in terms o horizontalstability is especially important becausethe construction is relatively light. Acommon practice or buildings with sixor seven oors is to build the ground

oor in concrete and secure the timberstructure to the concrete. Wind loads

are trans erred via joist elements andshear walls to the ground. Good stabilityis achieved by utilizing diaphragm action.

An important consideration whendesigning multi-storey buildings witha load-bearing wood rame is soundtrans er. E ective solutions are nowavailable to prevent sound rom sprea-ding between the oors and apart-ments without putting the stabilityo the building at risk.

Just as with single amily houses,multi-storey buildings made o timbercan be given an outer architecturaldesign that suits the location where

the building is erected.

1 Lentz, Shelby, Shaking it up a test to improve mid-rise, wood ramed building design, 2009. GoStructural.com.

The ull-scale earthquake test. Japans massive E-De ense Shake Table, the largest shake table in the world

Misawa


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Curtain walls/In ll wallsIn many countries in ll walls made romtimber are becoming an increasinglycommon solution, together with load-bearing rames made rom concrete orsteel. External walls o this type are de-signed only to take the load o the wallcomponents own weight and the windloads that directly a ect the compo-nent. The component has a low weightand can be pre abricated in a actory,which is a great advantage. In ll wallsmade o timber have very good insula-

tion characteristics. The increasinglystringent requirements or energy e -

cient buildings in various countries areamong the main driving orces behindthe use o this wall solution.

The component can be clad with anexternal layer o plaster, brick, woodenpaneling or other sheathing material inorder to match the buildings design andsurrounding buildings.

There are two main ways o tting tim-ber rame elements into the steel, con-crete or masonry structure. Either thepanels can be tted into or partly intothe structure or outside the structure.

Excellent thermal insulation proper -

ties are easily achievable. The usable building area is signi -

cantly increased (as compared toa similar insulated building withmasonry walls) because o lesserwall thickness.

Savings in on-site labour and con -struction time through a systematicof-site manu acturing process.

From an environmental (LCA) per -spective, timber rame structuresvirtually always per orm best.

The in- ll timber frame wall paneltechnique allows a wide range o architectural possibilities and clad-ding materials.

The primary benefts o thetechnique are

Wood infll walls in a concrete rame.


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Swedish Wood spreads knowledge, provides inspiration and encourages deve-lopment relating to wood, wood products and wood construction. The goal isto increase the use of wood in Sweden and in selected international marketsthrough information and inspiration.

Swedish Wood is a department within the trade and employer organisation theSwedish Forest Industries Federation . Swedish Wood is supported by theSwedish sawmill sector.

Box 55525SE-102 04 Stockholm, SwedenTel: +46 8 762 72 60

[email protected]

Photos: Per Bergqvist,ke E.son Lindman, Setra Group, Willa Nordic.Pictures or which no copyright holder could

be identifed have been attributed to unknownphotographer. Anyone who has in ormation

about possible copyright holders in these cases is encouraged to contact Swedish Wood.

Swedish Forest Industries Federation 20128

Partition walls/Inner walls

Extensions

Wood rame in combination with boardmaterial is a very common solution whenit comes to inner walls which will not bearany loads. These walls are used or divi-ding up rooms but can also be designedso that they can cope with the re andsound requirements placed on apartmentpartition walls.

Timber ofers great potential or chan-ging and modernizing existing, olderbuildings which are ofen constructed

rom concrete, mainly through additionalstories or extensions to roo s.

The simplest method is to t the oldbuilding with a new roo designed sothat a number o apartments can bebuilt into the attic space. The space canalso be used or placing installations or

improving energy e ciency and heatexchangers or ventilation.

As timber structures are light, thereare ofen margins or building additionalstories. In such cases, the use o pre a-bricated components is ofen suitable.Naturally the design must be veri ed sothat there is a margin or absorbing theadditional vertical loads and ensuringhorizontal stability.

Inner wall01. Vertical stud 02. Sill 03. Floorjoist

04. Noggin piece 05. Chipboard 06. Gypsum wall board 07. Sound insulation

Roo construction01. Roo tile 02. Batten 03. Counter batten 04. Roo ing elt 05. Tongued and grooved timber 06. Air gap 07. Masonite board 08. Insulation 09. Plastic oil 10. Secondary spaced boarding 11. Insulation 12. Gypsum board

Partition wall 01. Vertical stud 02. Sill 03. 2 x Gypsum wall board 04. Fine insulation 05. Rubber gasket 06. Sound insulation 07. Net to hold fne insulation

Three additional storeys in wood added to anexisting concrete building.

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Swedish SFIF Building With Wood