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Stora Enso Building and Living provides wood-based products and innovations for construction and interior decoration, as well as solid biofuels for the energy sector. Building and Living products address living, building and packaging needs. The products are recyclable, and made from high-quality renewable European pine or spruce. You can find more information on: www.storaenso.com/buildingandliving

CLT – Cross Laminated Timber freedom of design and architecture

Stora Enso Building and Living Building Solutions E-Mail: clt.info@storaenso.com www.storaenso.com/buildingandliving www.clt.info

Š Stora Enso Building and Living 2012. Printed on MultiArt Silk 250 g. All rights reserved.

2012 the second CLT plant started its production in Ybbs/Donau (AT). Thus achieving an annual production capacity of 125.000 m3 of CLT boards, which is equivalent to about 2,500 single-family homes.

www.clt.info www.storaenso.com


CLT – Cross Laminated Timber

Sustainable construction Renewable natural wood is an ecologically sound choice of construction material - a responsible choice in the battle against climate change. As a tree grows, it binds carbon dioxide that is stored in the walls of a massive wood building for centuries. At the same time, new forests grow with solar energy, and through photosynthesis the trees bind more carbon dioxide, slowing down climate change. In Europe, the natural growth of forests far exceeds the level harvested. Stora Enso is committed to sustainable forestry and does not buy wood from conservation or protected areas. Carefully selected, high-quality spruce is used as the raw material for the production of CLT. The environmental friendliness of wood as a construction material is indisputable. The energy consumption in the industrial production of massive wood boards is only one third of the amount used for the equivalent concrete production. Production planning is carried out carefully to ensure the efficient use of materials. Wood by-products, such as sawdust, are utilized in energy production.

Cross Laminated Timber (CLT) is a massive wood building material consisting of bonded, cross-laminated single layers called lamellas. The CLT structure is formed with 3, 5, 7 or more lamella layers which vary in thickness. Formaldehyde-free and environmentally friendly adhesives are employed for bonding. The cross structure of CLT components guarantees integral stability. Stora Enso manufactures CLT in large, 2.95 x 16 m boards which enable fast construction and lead to very few butt joints between the boards. This leads to better air tightness. The tailor-made, ready-to-install prefabricated construction boards are prepared in our factories and loaded to ensure easy and immediate assembly.

Facts that speak for a CLT-building: • • • • • • • •

Flexibility of the construction (from traditional to modern buildings) Ecological construction Short construction time Simple assembly Comfort and a healthy indoor climate Energy cost savings Preserves value and safety for generations Easy to plan and calculate

Promoting health and well-being Massive wood has the ability to absorb moisture from the indoor air, which it releases back after the indoor air has dried out. The optimal healthy indoor air humidity is 30–55%. The more massive wood used in the inner walls of a building, the better indoor humidity remains at a level optimal for health. It is easy to breathe in a massive wood building, making it an ideal choice for anyone suffering from allergies or other respiratory problems. Fire safety Massive wood is much more fire-resistant than is perceived. It can withstand fire even better than concrete or steel posts. CLT has a water content of approximately 12%, and before the wood can catch fire, this water must evaporate. The surface charring protects the inner layers of the CLT so that in a fire, a massive wood construction will char but will not collapse like buildings constructed from steel or concrete. In a building, what will burn is not the wood or the wood structure, but the plastic in the finishings and furniture.


Safe even on unstable grounds Due to the structural strength and flexibility of the natural wood fibres in CLT, buildings constructed from CLT boards are suited for earthquake zones. Because massive wood is lighter than concrete, the building's weight does not amplify the shaking. Following an earthquake there can be a risk of a fire if a gas pipe bursts, but contrary to widespread belief, well-designed massive CLT-buildings can perform very well in these conditions. In recent years, six- and seven-storey massive wood buildings have been tested on the world's largest shaking table in Japan at simulations of magnitude 7.5 earthquakes and have shown almost no damage.

Sustainability CLT is produced from PEFCcertified wood (spruce) from sustainably managed forests and controlled sources. PEFC certification ensures that CLT is produced to the highest ecological, social and ethical standards.

Energy efficient

Cost effective

• air and wind-tight structure • passive level easily available through prefabrication • due to the thermal mass of CLT, the wood absorbs solar energy during the day and releases it to the inside air during the cooler night time, saving up to 20% in heating energy

• shorter erection time due to the prefabricated CLT boards and no curing time needed • simple to design and calculate • air and wind-tight structure - no separate wind barrier needed • due to the material, the building process is far less likely to be interrupted in very cold weather conditions • simple installation - no extensive training of builders needed • project meets sustainability objectives when CLT is used as the main structural material • passive level available with reasonable costs Freedom of design • endless possibilities in design, style and architecture - the wood can be machined as designed • can be combined with any other building material • flexible system - high structures and large openings • light weight - an ideal solution in areas where the loads of the building are an issue • creative freedom - the frame material can be left visible or covered with other materials

The quality speaks for itself Sustainably produced, carefully refined and with high quality processing, CLT reaches a particular level of quality. Crosswise gluing in CLT provides enormous static and dynamic resistance and brings valuable building physics benefits. CLT boards are tailor-made on a CNC machine and surface grind. They come in either invisible, industrial-visible or visible range where the latter is subjected to a careful visual selection of individual lamellas and an even finer grinding process.

CLT is a licensed and certified building product whose production is subject to rigorous external controls. They guarantee the high quality and safe construction of CLT. For more information about CLT, please visit our website:

www.clt.info


CLT – standard structures

Applications

primarily as a wall, ceiling or roof boards

Maximum width

2.95 m

Maximum length

16.00 m

Maximum thickness

400 mm

Layer structure

3, 5, 7, 8 or more layers out of cross-laminated single-layer edge-glued panels

Joining

Any cuts possible

Wood species

Spruce or spruce with pine-middlelayers. Other wood species such as larch on request.

L3s

Moisture content

12% +/– 2%

L5s

Optical surface quality

3 different gradings: Nonvisible-, industrial-visibleand visible-quality

Surface quality

Factory-sanded; both sides

Weight

Approx. 470 kg/m³ CLT

Water vapour diffusion resistance μ

20 – 50

Thermal conductivity λ

0,11 W/(mK)

Specific heat capacity cp

1600 J/(kgK)

Service class

1 and 2

C-boards Nominal thickness [mm]

Designation [--]

CLT – construction details

Technical data

Layers [--]

Lamella structure [mm] C

L

C

L

C

60

C3s

3

20

20

20

80

C3s

3

30

20

30

90

C3s

3

30

30

30

100

C3s

3

30

40

30

120

C3s

3

40

40

40

100

C5s

5

20

20

20

20

20

120

C5s

5

30

20

20

20

30

140

C5s

5

40

20

20

20

40

160

C5s

5

40

20

40

20

40

L

C

C3s

C5s

L-boards Nominal thickness [mm]

Designation [--]

Layers [--]

Lamella structure [mm] L

C

L

C

L

C

L

60

L3s

3

20

20

20

80

L3s

3

30

20

30

90

L3s

3

30

30

30

100

L3s

3

30

40

30

120

L3s

3

40

40

40

100

L5s

5

20

20

20

20

20

120

L5s

5

30

20

20

20

30

140

L5s

5

40

20

20

20

40

160

L5s

5

40

20

40

20

40

180

L5s

5

40

30

40

30

40

200

L5s

5

40

40

40

40

40

160

L5s-2*

5

60

40

60

180

L7s

7

30

20

30

20

30

20

30

200

L7s

7

20

40

20

40

20

40

20

240

L7s

7

30

40

30

40

30

40

30

220

L7s-2*

7

60

30

40

30

60

240

L7s-2*

7

80

20

40

20

80

260

L7s-2*

7

80

30

40

30

80

280

L7s-2*

7

80

40

40

40

80

300

L8s-2**

8

80

30

80

30

80

320

L8s-2**

8

80

40

80

40

80

L5s-2*

L7s

* 5- / 7-layer; outer layers consisting of 2 lengthwise layers ** 8-layer; outer layers and the inner layer consisting of 2 lengthwise layers Width (charged widths): Length (production lengths):

245 cm, 275 cm and 295 cm From min. production length 8.00 m per charged width to max 16.00 m. Increments of 10 cm.

L7s-2*

L8s-2**

CLT - Cross Laminated Timber - EN