BUILDING INNOVATION. BUILDING LIFE.

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2 BUILDING INNOVATION. BUILDING LIFE. CLT solid wood elements There are many reasons to choose Stora Enso CLT Elements. Our innovation and quality will convince you: Easy to work & superior quality Elements available in large formats up to 2.95 m x 16 m Composed of edge-glued panels with every joint bonded Very easy to cut and assemble directly at the construction site Minimum time requirements for construction and assembly Pre-fabricated elements for use in dry construction Natural & sustainable Formaldehyde-free adhesives Healthy indoor climate solid wood regulates the room climate and filters toxins from the air Sustainable manufacturing process results in an optimum CO 2 and energy scorecard Combinable & high quality Virtually no settling Highly compatible with mineral-based building materials (additions, added floors, etc.) No vapour brake or barrier normally required diffusion-open construction without foil or adhesive tape More mass-efficient heat storage than wooden frame structures Both non-visible and visible quality grade elements with sanded surface Innovative & safe Air- and wind-tight Highly suitable for earthquake zones Clear separation of the load-dispersing layer from the insulating layer

3 STRUCTURE OF CLT using single-layer boards Our CLT solid timber panels consist of bonded single-layer boards which are cross-laminated with each other. The max. production width is 2.95 m and the max. production length m. Example: Design of a 5-layer CLT solid timber panel Narrow-side bond Flat dovetailing Surface bond + Narrow-side bond + max m max m + = +

4 CLT - CROSS LAMINATED TIMBER Solid wood elements General information on CLT Use Maximum width Maximum length Maximum thickness Layer structure Wood species Grade Wall, ceiling and roof element in homes and other buildings 2.95 m m 300 mm Bonded cross-laminated single-layer panels Spruce (larch on request) C24 (maximum 10% C16 allowable) Moisture content 12% ± 2% Bonding adhesive Visual quality Weight Formaldehyde-free adhesives for edge bonding, finger jointing and surface bonding Non-visible and visible quality; the surface is sanded in both cases 5.0 kn/m³ in accordance with DIN :2002, for structural analyses; A Actual weight: approx. 470 kg/m³ Special information on CLT Change in shape with change in moisture content Swelling and shrinkage in accordance with DIN 1052:2008 below the fibre saturation level: In panel plane: 0.02% change in length per 1% change in timber moisture content Perpendicular to panel plane: 0.24% change in length per 1% change in timber moisture content Fire rating Water vapour diffusion resistance µ Thermal conductivity λ Specific heat capacity c p Airtightness In accordance with the ruling by the Commission in 2003/43/EC: Timber components apart from floors Euroclass D-s2, d0 Floors Euroclass Dfl-s1 To EN to 50 To EN W/mK To EN J/kgK CLT elements are made of single-layer panels, as a result of which they are extremely airtight. The airtightness of a 3-layer CLT element and of element butt joints has been tested to EN , where it was found that that the volumetric rates of flow were outside the measurable range. Usage classes / usability Usable in usage classes 1 and 2 to EN

5 STRUCTURAL ANALYSIS Cross Laminated Timber General information on planning load-bearing structures with CLT Because of the single-layer panels which are bonded alternately at right angles to each other the load is transferred in two axes which was the preserve of reinforced steel structures in the past. The advantage of this is more flexible room design at the planning stage; designs can also be simplified, and lower bare ceiling heights are possible. Although diagonally projecting or point-supported structures require greater planning input, they are perfectly feasible. CLT elements have a particularly high load capacity since the load-bearing width generally extends across the entire element width because of the transverse layers. The high inherent stiffness of CLT also has a positive impact on bracing a building. CLT calculation method The difference from sizing solid timber or glulam lies in the loading of the transverse layers. In a CLT element a load at right angles to the panel plane (e.g. a snow load on a flat roof) generates a shear load in the transverse layers which acts at right angles to the direction of grain. This shear load is termed rolling shear since the wood fibres roll off at right angles in the event of a fracture. As a result of the low shear strength or stiffness of the transverse layer (load at right angles to the grain), the stresses or deformations that occur cannot be ignored. Calculations are carried out in accordance with the lamination theory, taking account of shear distortions. There are now various options for calculating cross-laminated timber; one of these is the theory of flexibly connected layers (also termed the gamma method. The gamma method is the commonest method and is also described in ETA-08/0271. Fastenings Verification of the fastenings is described and regulated in the approvals.

6 SINGLE-SPAN BEAM Deformation nk gk l In accordance with approval Z DIN 1052 (2008) and/or EN (2006) Permanent load gk*) [KN/m] Imposed load SPAN OF SINGLE-SPAN BEAM l nk [KN/m] 3.00 m 3.50 m m 4.50 m m 5.50 m 6.00 m 6.50 m 7.00 m The CLT self-weight is already taken into account in the table at ρ = 500 kg/m³! Service class 1, imposed load category A (ψ 0 = 0.7; ψ 1 = 0.5; ψ 2 = 0.3) Ultimate limit state: a) Verification of bending stresses b) Verification of shear stresses k mod = 0.8 Serviceability: Fire resistance: β = 0.65 mm/min R0 R30 R60 R90 a) Quasi-constant design situation: w fin = l / 250 b) Infrequent design situation: w Q,inst = l / 300; w fin - w G,inst = l / 200; k def = 0.6 This table specifies the required thicknesses for the normal design situation (R0). The colour shading represents the fire resistance rating which is also attained with this thickness. If a higher fire resistance rating is required, a separate analysis must be carried out. This table is for preliminary design purposes only and is not a substitute for a structural analysis! Status 06/09

7 TWO-SPAN BEAM Deformation l1 l2 In accordance with approval Z DIN 1052 (2008) and/or EN (2006) Permanent load gk*) [KN/m] Imposed load SPAN OF TWO-SPAN BEAM l 1 l 2 = 0,8 l 1 bis 1,0 l 1 nk [KN/m] 3.00 m 3.50 m m 4.50 m m 5.50 m 6.00 m 6.50 m 7.00 m 57 L3s The CLT self-weight is already taken into account in the table at ρ = 500 kg/m³! Service class 1, imposed load category A (ψ 0 = 0.7; ψ 1 = 0.5; ψ 2 = 0.3) Ultimate limit state: a) Verification of bending stresses b) Verification of shear stresses k mod = 0.8 Serviceability: Fire resistance: β = 0.65 mm/min R0 R30 R60 R90 a) Quasi-constant design situation: w fin = l / 250 b) Infrequent design situation: w Q,inst = l / 300; w fin - w G,inst = l / 200; k def = 0.6 The analysis was carried out using the imposed load on one field. In the event of imposed loads on both fields, the required ceiling thickness may be reduced. This table specifies the required thicknesses for the normal design situation (R0). The colour shading represents the fire resistance rating which is also attained with this thickness. If a higher fire resistance rating is required, a separate analysis must be carried out. This table is for preliminary design purposes only and is not a substitute for a structural analysis! Status 06/09

8 APPROVALS of CLT German Institute for Structural Engineering As the approval body in Germany, the German Institute for Structural Engineering (DIBt) grants general building inspection approvals for building products and designs. The general building inspection approval regulates the manufacture and use of CLT and is the basis for the Ü mark, the German conformity mark. European Technical Approval (ETA) The ETA regulates the manufacture and use of CLT in Europe and is the basis for the CE mark. PEFC PEFC Programme for the Endorsement of Forest Certification Schemes is the mark for wood and paper products from environmentally, economically and socially sustainable forestry operations along the entire processing chain. For customers the PEFC mark is confirmation that the purchase of a marked product guarantees and supports environmentally sound forestry management. It guarantees that the product has been subject to monitoring in accordance with rigorous criteria from the forest to the end product. Evidence of compliance is provided by Stora Enso Timber AG and is regularly checked by independent bodies.

9 ABOUT US & LEGAL NOTICE Stora Enso Stora Enso Stora Enso is an integrated forest products company whose production range covers the following fields: Newsprint Book paper Magazine and fine paper Consumer boards Industrial packagings Timber products (Stora Enso Timber) Stora Enso recorded sales of EUR 11 billion in 2008 and employs some 32,000 staff in more than 35 countries on five continents. Stora Enso has a production capacity of 12.7 million tonnes and paper and cardboard and 6.9 million cubic metres of cut timber products, of which 3.2 million cubic metres are processed in-house. Stora Enso shares are traded on the Helsinki and Stockholm Stock Exchanges. For further information please visit: Stora Enso Timber Stora Enso Timber is a manufacturer of timber products, offering customer-focused solutions worldwide for the construction industry, carpenters and joiners and timber retailers. With a production capacity of 6.9 million m³ cut timber products incl. 3.2 million m³ further processed products Stora Enso Timber recorded annual sales in 2008 of EUR 1.5 billion. The company employs some 5000 staff in 26 production centres and in its own sales and distribution companies around the world. For further information please visit: Legal notice Stora Enso Timber Bad St. Leonhard GmbH Wisperndorf 4 A-9642 Bad St. Leonhard Tel.: +43 (0) Fax: +43 (0) Managing director: Herbert Jöbstl Commercial Register: FN v Commercial Court: Krems/Donau Regional Court VAT Reg. No.: ATU Contact: office.leonhard@storaenso.com E info@solidtimber.co.uk