DEUTSCHES INSTITUT FÜR BAUTECHNIK Anstalt des öffentlichen Rechts

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1 Page 1 of the national technical approval no. Z of 7 DEUTSCHES INSTITUT FÜR BAUTECHNIK Anstalt des öffentlichen Rechts Berlin, of 26 July 2007 Kolonnenstrasse 30 L Telephone: +49(0) Fax: +49(0) Ref. no.: II /06 National technical approval Approval number: Z Applicant: KAUFMANN Holz GmbH Vorderreuthe Reuthe AUSTRIA Subject of approval: Kaufmann HT 20 Plus timber formwork beam Valid until: 31 July 2012 The above-mentioned subject of approval is hereby granted national technical approval. * This national technical approval comprises seven pages and three appendices. * This national technical approval replaces the national technical approval no. Z of 13 July The subject was first granted national technical approval on 12 April 1983.

2 Page 2 of the national technical approval no. Z of 7 I. GENERAL PROVISIONS 1 With the national technical approval, the usability or applicability of the subject of approval in the sense of the Building Regulations of the Land (Landesbauordnungen) is verified. 2 The national technical approval does not replace the permits, consents, and certificates which are legally prescribed for the implementation of construction projects. 3 The national technical approval is granted without prejudice to the rights (private property rights in particular) of third parties. 4 Manufacturers and distributors of the subject of approval must, without prejudice to further regulations under "Special Conditions", provide the user or handler of the subject of approval with copies of the national technical approval, and must inform the user or handler that the national technical approval must be present at the place of use. Upon request, copies of the national technical approval are to be made available to the participating authorities. 5 The national technical approval may only be copied in full. Publication of excerpts requires the consent of Deutsches Institut für Bautechnik. Texts and illustrations from advertising material may not contradict the national technical approval. Translations of the national technical approval must include the remark "This translation of the original German version has not been certified by Deutsches Institut für Bautechnik." 6 The national technical approval is granted revocably. The provisions of the national technical approval can be extended and altered after the fact, especially if this is necessitated by new technical findings.

3 Page 3 of the national technical approval no. Z of 7 II. SPECIAL CONDITIONS 1 Generic type and application of construction product 1.1 Subject of approval The Kaufmann HT 20 Plus timber formwork beams are glued, massive I-shaped beams with a nominal height of 200 mm, and with the shapes and dimensions indicated in the appendices (e.g. see appendix 1). They are up to 15.0 m in length. They consist of an upper and lower softwood flange, and a triple-layered, glued softwood web. 1.2 Field of application The timber formwork beams may only be used as formwork beams for ceiling formworks and wall formworks, and during use may only be subjected to loads such as those which arise when directly supporting ceiling formwork or wall formwork in concrete construction work, however not to larger concentrated loads (e.g. support beams). The span of the beams may not exceed 4.00 m. 2 Provisions for the timber formwork beams 2.1 Properties and composition Flanges The upper and lower flange of the Kaufmann HT 20 Plus timber formwork beams must consist of softwood (solid wood) with a width of 80 mm and a height of 40 mm. For deviations in cross-section, dimension tolerance class 2 as per DIN EN 3361 shall apply. For the flanges, only softwood as per DIN 40742, conforming to at least sorting class S 10, may be used. With regard to compression wood, the wood for the flange timbers must conform to sorting class S 13. The average growth ring width may not exceed 4 mm. The flange timbers must be planed on four sides, and the edges of the planed flange timbers must be chamfered Webs The triple-layered, glued softwood webs of at least sorting class S 10 must have a thickness of 30.0 mm ± 0.9 mm (variants I and II) or 26.8 mm ± 0.9 mm (variants III and IV). The thickness of the webs' layers must be: Variant I outer layer 7.0 mm ± 0.2 mm, inner layer 16.0 mm ± 0.5 mm. Variant II outer layer 5.8 mm ± 0.2 mm, inner layer 18.4 mm ± 0.5 mm. Variant III outer layer 7.0 mm ± 0.2 mm, inner layer 12.8 mm ± 0.5 mm. 1 DIN EN 336: Structural timber Sizes, permissible deviations - 2 DIN : Sorting of wood according to bearing capacity Part 1: Softwood sawn timber

4 Page 4 of the national technical approval no. Z of 7 Variant IV outer layer 5.8 mm ± 0.2 mm, inner layer 15.2 mm ± 0.5 mm Adhesive For manufacture of the beams, an adhesive as per DIN EN 3013 must be used, which meets the requirements of adhesive type I as per DIN EN 301, based on tests as per DIN EN to -44 and with regard to the properties of use as per DIN The adhesive must be approved for the gluing which occurs with the Kaufmann HT 20 Plus timber formwork beams, and for use of the beam as a formwork beam (freely integrated). Alternatively, an adhesive with a national technical approval for this use may be applied. 2.2 Manufacturing and labelling Manufacturing The Kaufmann HT 20 Plus timber formwork beams must be 200 mm ± 2 mm in height The webs' three layers are to be glued together in a slab press. On the outer layers, the grain must run parallel to the beam's longitudinal axis, and on the inner layer the grain must run perpendicular to the beam's longitudinal axis (see appendices 1 and 2). For the outer layers, the short sides must also be glued The webs may include finger joints as per appendix 1 or appendix 2. The flanges may include finger joints as per DIN The web is to be connected to the flanges by means of finger jointing as per appendices 1 to 3. The finger joint dovetailing for the web must occur on the left-hand flange surface (on the broad side which is furthest from the pith) All finger joints must fit correctly at the time of gluing (sufficient gap at the finger base to guarantee the necessary press fit in the dovetail edges) The manufacturers of the timber formwork beams must possess a valid certificate as verification of the suitability for gluing of this type of construction as per DIN The joining and gluing of the timber formwork beams must take place in a special facility, suitable for this purpose. The gluing may only take place in the gluing rooms specially equipped for this purpose. The temperature in the gluing room may not fall below 18 C or rise above 25 C during gluing. After gluing, the temperature may be increased for faster curing of the adhesive. 3 DIN EN 301: Adhesives, phenolic and aminoplastic, for load-bearing timber structures Classification and performance requirements- 4 DIN EN 302-1: Adhesives for load-bearing timber structures Test methods Part 1: Determination of bond strength in longitudinal tensile shear DIN EN 302-2: Adhesives for load-bearing timber structures Test methods Part 2: Determination of resistance to delamination DIN EN 302-3: Adhesives for load-bearing timber structures Test methods Part 3: Determination of the effect of acid damage to wood fibres by temperature and humidity cycling on the transverse tensile strength DIN EN 302-4: Adhesives for load-bearing timber structures Test methods Part 4: Determination of the effects of wood shrinkage on the shear strength 5 DIN 68141: Wood adhesives Determination of properties of use of wood adhesives for loadbearing timber structures 6 DIN : Wood finger-jointing Part 1: Finger jointing of softwood for load-bearing structures 7 The following technical construction regulations shall apply: DIN : Timber structures; Design and construction DIN : Timber structures; Mechanical joints DIN /A1 to -2/A1: Amendment A1 and DIN 1052: Design of timber structures General rules and rules for buildings

5 Page 5 of the national technical approval no. Z of 7 The wood which is to be glued must have a temperature of at least 18 C. The processing specifications for the adhesives are to be observed It is not necessary to apply a preservative wood treatment to the timber formwork beams Labelling The timber formwork beams must be labelled by the manufacturer with the conformity sign (Ü sign) in accordance with the states' conformity sign regulations. The labelling may only occur if the requirements of section 2.3 are met. The name of the manufacturing plant, the approval number Z , the subject of approval, and the day of manufacture, must be permanently indicated on the timber formwork beams. 2.3 Verification of conformity General The confirmation of the Kaufmann HT 20 Plus timber formwork beams' conformity with the provisions of this national technical approval must occur for every manufacturing plant by means of a certificate of conformity based on factory production control and regular external control thereof, including an initial inspection of the Kaufmann HT 20 Plus timber formwork beams in accordance with the following provisions. For granting of the certificate of conformity, and for external control, including the product testing which must be conducted for these purposes, the manufacturer of the Kaufmann HT 20 Plus timber formwork beams must engage a suitably accredited certification body, and a suitably accredited inspection body. The certification body is to provide Deutsches Institut für Bautechnik with a copy of the certificate of conformity granted by the certification body, by way of notification Factory production control Factory production control must be set up and conducted in every Kaufmann HT 20 Plus timber formwork beam manufacturing plant. The term 'factory production control' refers to the continuous surveillance of production, to be performed by the manufacturer, with which the manufacturer ensures that the construction products which they produce comply with the provisions of this national technical approval. The factory production control of Kaufmann HT 20 Plus timber formwork beams shall include at least the following actions: - specification and verification of raw materials and constituents: dimensions of the flanges and webs dimensions and fit of the finger joints in the flanges and in the web timber species sorting class expiry, manufacture, or delivery date of the adhesive, and indication of the adhesive charge presence of the Ü sign or CE marking of the source materials for the current use - control and tests to be carried out during manufacture: moisture of wood fit of the joint between flange and web room climate during gluing and curing - verifications and tests to be carried out on the finished construction product: dimensions of the beams visual inspection of the beams

6 Page 6 of the national technical approval no. Z of 7 The results of factory production control are to be recorded and evaluated. The records must include at least the following information: - designation of the construction product and of raw materials and constituents - type of control or testing - date of manufacture and of testing of the construction product and of the raw materials or constituents - result of the control and testing and, if appropriate, comparison with requirements - signature of the person responsible for factory production control The records are to be kept for at least five years, and are to be submitted to the inspection body engaged for external control. Upon request, they are to be submitted to Deutsches Institut für Bautechnik, and to the supreme construction supervision authority responsible. In the event of an unsatisfactory test result, the manufacturer must immediately perform the actions necessary to rectify the shortcoming. Construction products which do not meet the requirements are to be handled in such a manner as to exclude any possibility of these products being mistaken for products which do conform. After rectification of the shortcoming, the relevant test is to be repeated immediately, if technically possible, and if necessary in order to verify that the shortcoming has been rectified External control The factory production control in every Kaufmann HT 20 Plus timber formwork beam manufacturing plant must be regularly checked by means of external control, at least twice a year. As part of the external control, an initial inspection of the Kaufmann HT 20 Plus timber formwork beams is to be conducted, and samples can also be taken for audit testing. The respective accredited inspection body is responsible for the sampling and inspections. Each month, as part of the external control of the Kaufmann HT 20 Plus timber formwork beams, 5 beams with manufacturing dates distributed relatively evenly throughout the respective month are to be taken as samples from the store in the manufacturing plant. If fewer than 10,000 running metres are manufactured each month, one beam is to be sampled for every 2,000 running metres (approximately). These beams are to be labelled in an unmistakeable manner. Upon delivery of these beams to the inspection body, testing is to be conducted in order to ascertain whether the requirements stipulated in the national technical approval are met. With regard to the permissible stress resultants specified in section 3, in six tests in succession with the same cause of breakage, the beams must on average achieve at least a 3-fold safety margin, and the lowest individual value must amount to at least a 2.5-fold safety margin. During testing, it must be ensured that the beams are tested in such a manner that the finger joints of the flanges and webs are also measured in unfavourable alignments. The results of the certification and external control must be kept for at least five years. Upon request, the certification body or inspection body is to submit these results to Deutsches Institut für Bautechnik, and to the supreme construction supervision authority responsible.

7 Page 7 of the national technical approval no. Z of 7 3 Design provisions 3.1 General For the design, DIN 1052 and DIN in particular shall apply, unless otherwise stipulated in the following. 3.2 Design as per DIN : The following specified stress resultants may not be exceeded at any position on the timber formwork beam: max. Q = 11.0 kn (maximum permissible shear force) max. M = 5.0 knm (maximum permissible torsion moment) Notwithstanding DIN : , section , reduction of the shear forces is not permissible. For the maximum permissible bearing pressure, max. D, DIN : , table 5, row 5a (value without larger indentations) and section of this standard shall apply. 3.3 Design as per DIN 1052: The following specified characteristic load-bearing capacities may not be exceeded at any position on the formwork beam: Vk = 24.0 kn (characteristic threshold value for shear force bearing capacity) Rb,k = 47.8 kn (characteristic threshold value for bearing resistance) Mk = 11.0 knm (characteristic threshold value for bending capacity) Notwithstanding DIN 1052: , section (2) and (3), reduction of the shear forces is not permissible. The modification factor kmod = 0.9 may be adopted (implementation under typical site conditions in service class 2 as per DIN 1052: , in which moisture content of 20% or less is present), unless a lower value is necessary due to local conditions. The partial safety factor for actions is to be set to = 1.5, and the partial safety factor for the strength property to M = 1.3. Upon verification of pressure perpendicular to the wood's grain, the lateral pressure factor kc,90 must be set to 1.0. For the characteristic resistance pressure perpendicular to the wood's grain fc,90,k, the value for the strength class C 30 may be applied. 4 Provisions for the implementation The span of the timber formwork beams may not exceed 4.00 m. The formwork shell is to be laid directly onto the upper flange, and nailed in place. The timber formwork beams are to be secured to prevent tipping, according to the static loading requirements. 5 Provisions for use, maintenance and care Before each use of the timber formwork beams, the installer is to check that they are in a sound condition. Beams which are weakened due to damage or decay are to be excluded from use. Henning Certified 8 DIN 4421: Falsework; Calculation, design and construction