FREQUENTLY ASKED QUESTIONS

Transcription

1 FREQUENTLY ASKED QUESTIONS

2 CONTENT PAGE FREQUENTLY ASKED QUESTIONS 0.1 KLH Cross Laminated Timber Panels What are cross laminated timber How are the boards glued together? What can KLH panels be used for? What is the level of waste in the production of KLH Are KLH structures like timber frame structures? Can KLH panels be left exposed on the interior of a building? Can KLH panels be cut to the dimensions of architectural drawings? What are the cost savings from using KLH How quickly can other services begin work on the structure once KLH panels have been erected? 0.2 Manufacturing and Design What capacity does your factory have for manufacturing How do you manufacture the cross-laminated timber What does timber engineering cover in your quote? Is the routing of KLH panels included in the quote? Is sound insulation included in your quote? Is fire protection included in your quote? 0.4 Transportation, Delivery and On-site Management What size of panels can be transported to the UK? How do you transport the timber How are the panel deliveries scheduled? Can KLH UK deliver panels to any site? Is the KLH erection process integrated into the overall cosntruction programme? Is there a KLH site manager on-site during the erection of the timber structure? Do KLH organise the cranes on-site and is it included in the quotation? Is the cost of scaffolding included in the quotation? Is a method statement written for the on-site erection process? Can the building be erected in shorter timescales, if required? After installation is the roof water tight? What does the method statement contain risk assessment? Do KLH UK undertake post assembly inspections? 0.5 Contact Us 0.3 Technical Characteristics and Approvals What are the technical characteristics of KLH timber What are the achievable u-values when building with KLH timber What airtightness level is achievable using KLH crosslaminated timber How does your product respond to concerns about lack of thermal mass in lightweight construction and potential overheating of dwellings? Are KLH external timber walls insulated? What are the technical characteristics of KLH timber

3 0.1 KLH CROSS LAMINATED TIMBER PANELS What are cross laminated timber Cross-laminated timber panels are produced from kiln dried spruce/fir boards which are stacked at right angles and glued together over their entire surface. Depending on the purpose and static requirement, the plates are available in 3, 5, 7 or more board layers. How are the boards glued together? Gluing is carried out with PUR adhesive which is completely solvent and formaldehyde free and tested in accordance with DIN and other strict criteria by MPA Stuttgart and approved for the production of load-bearing timber construction elements and special construction methods in accordance with DIN 1052 and EN 301. Crosswise gluing at high pressure reduces the wood's expansion and shrinkage to an insignificant level. What can KLH panels be used for? KLH solid timber panels can be used as large wall, floor and roof elements. What is the level of waste in the production of KLH The production process produces zero-waste as all off-cuts, wood shavings and sawdust are manufactured into biomass pellets, and used to generate heat and power in the KLH Massivholz GmbH factories, and the excess is sold to local CHP plant. Are KLH structures like timber frame structures? No, KLH panels are solid cross-laminated timber building elements - industrially prefabricated panels which have a structural performance more akin to precast concrete panels. Can KLH panels be left exposed on the interior of a building? Yes, KLH panels are available in 3 visual qualities: non visual quality industrial visual quality domestic quality Domestic quality panels can be left exposed within the interior of a building, but should be treated with some kind of surface treatment (wax, oil) or spread of flame treatment (dependent on building regulations). Please see 'Surface Quality' document for further information. Can KLH panels be cut to the dimensions of architectural drawings? The panels are cut and processed in the KLH Massivholz GmbH factories, in Austria & Sweden, using state-of-the-art CNC technologies, resulting in excellent dimensional stability, both in overall panel size and for structural openings. Please see the 'CNC Processing' document for further information. What are the cost savings from using KLH There are a number of cost savings from using KLH panels, including: Less weight in the overall structure results in a more economic design of the substructure/foundations (less concrete) The load distribution of the panelised structure can reduce the thickness of the transfer slab (less concrete) Prelims can be reduced due to the shortened construction programme Programming can be enhanced by, for example, preordering windows the high degree of accuracy afforded by the CNC cutting process ensures that exact structural openings will be delivered to site. A KLH building offers a solid timber superstructure which has no interfaces with other trades or materials during the construction process; resulting in a simplified, 'low-risk', process which contributes to the delivery of a high-performance structure. How quickly can other services begin work on the structure once KLH panels have been erected? The clean, dry and relatively quiet erection process that KLH UK use ensures that no drying time is required on mulit-storey schemes following trades can be working immediately on the preceding floors if required. Based on our experience it is clear that there are time saving opportunities for the following trades*: Services approximately percent quicker Dry liners approx percent quicker Window & door installers approx percent quicker Insulation installers approx percent quicker Cladding installers approx percent quicker. * Conservative rates based on anecdotal evidence provided by main contractors. * Panels may require further sanding prior to treatment.

4 0.2 MANUFACTURE AND DESIGN What capacity does your factory have for manufacturing The KLH has factory capacity exceeding 750,000m² at two plants in Austria. How do you manufacture the cross-laminated timber KLH were the first manufacturer to introduce a high pressure physical press into the manufacturing process of cross laminated timber, which allows us to use polyurethane adhesive in the boards. The gluing takes place using solvent-free and formaldehydefree PUR adhesive from Purbond (HB 110, HB 530) - this adhesive is tested according to DIN and other strict criteria of the MPA Baden Württemberg, Otto Graf Institute Stuttgart and is recognised for the production of internal and external supporting timber components and special construction methods in accordance with DIN 1052 and EN 301. The glue is applied automatically over the whole surface - the percentage of adhesive is 0.5/m 3 and glue seam. A very highquality level of adhesion is achieved as a result of the physical pressing power of approx. 50 kn/m 2. This process has been patented by KLH. What does timber engineering cover in your quote? KLH UK's timber engineering services includes the member design and the connection design for the structural shell suitable for being submitted to building control. Is the routing of KLH panels included in the quote? The standard routing of KLH panels is included in our quotations, this includes:per panel: up to 2 openings (door/window) 5 holes to diameter 60mm 2 service runs Is acoustic performance considered in your quote? Acoustic insulation is not included in our quotes (only structural solution). Sound insulation should be covered by additional build ups - 2 sides of a panel cannot be left exposed, but in some situations one side can be left exposed. Is fire performance considered in your quote? No fire protection is not included in our quote, only structural solutions. Fire performance can be increased in the structural panel by increasing thickness if it is exposed, otherwise it should be covered by additional build ups. As sound insulation and fire protection can be part of the structural wall or additional build up (or even part/part) this should be subject to further discussions. How are the panels routed and how can I ensure that they are to my drawing specifications? KLH Massivholz GmbH have qualified and highly skilled operatives to oversee the cutting and processing of the panels to the exact requirements of the design, using state-of-the-art CNC technologies. This results in excellent dimensional stability, both in overall panel size and for structural openings. All the required design work for a project is undertaken in KLH UK's London office, as is the cutting data, by our in-house design team. They create fabrication drawings taken from the original architect's drawings incorporating the cross laminated timber panels, openings, joints and connections and transfer them to the factory in Austria or Sweden for cutting and processing on the state of the art CNC technologies. The management procedures include both technical and quality reviews to ensure that the panels that are produced are to the exact requirements of the design before they leave the factory and are transported directly to the construction site. Please see 'Design Process' document. Anything outside of this is an additional charge.

5 What is the lead in time for incorporating KLH panels into a building? The lead in time for KLH UK is 12 weeks: 6 weeks for producing and commenting on drawings (2 no. revisions) 6 weeks for production of panels, delivery to site and organisation of on-site activities (i.e. labour and crane). The lead in time begins once KLH UK have received the architect's final set of drawings and the engineer's calculations. Please see 'Design Process' document for further information. If KLH UK undertake the structural engineering for the project, please allow for an additional weeks. 0.3 TECHNICAL CHARACTERISTICS AND APPROVALS What are the technical characteristics of KLH timber The technical characteristics of KLH cross laminated timber panels are: Board Formats max. length: 16.50* m - max. width: 2.95 m At KLH UK we try to limit the maximum length to 13.5m in the UK because it is the most economical way of transporting the panels. Board Thickness Standard board thicknesses are between mm, but panels can be created up to 500mm if required. The board layers can be between 3-9 layers, standard layers are: 3 layers 60, 63, 78, 90, 94, 98, 102, 108 mm 5 layers 95, 101, 117, 125, 128, 146, 158, 162, 170, 182 mm 7 layers 202, 226, 256 mm Dimensional Stability parallel to board : negligible movement normal to board : 0.2 mm/m per % moisture outside standard 12% +/-2 Moisture 12% +/-2 kiln dried Fire Protection / Charring Rate 0.76 mm/min. - if several layers burn off 0.67 mm/min. - if only the cover layer burns off Airtightness Number of air changes up to passive house standard - depending on the structure of the boards down to 50pa (dependent on structural openings etc.) Thermal Performance α value 0.11 to 0.13 W/mK Specific heat capacity 2.10 kj/kgk ρ bulk density 5kN/m3 Further details on the technical characteristics of KLH's cross laminated timber panels can be found in the BRE Durability Report, which is available on request. What airtightness level is achievable using KLH crosslaminated timber The air tightness of a cross laminated timber panel construction depends on the density of the panels and on the design of the panel joints. Tests on cross laminated panels (1000 mm x 1000 mm) showed that 3-layer panels in visible industrial quality [isi] and 5-layer panels in non-visible quality [nsi] act as air tight panels. All panel joints are externally taped for airtightness the critical areas will therefore be the building interfaces i.e. windows, doors etc. Tests on completed buildings in the UK have resulted in performances of 1.7 (residential project) 4.0 (large span sports hall structure)m3/(h*m2) at 50 Pa; averaging at around How does your product respond to concerns about lack of thermal mass in lightweight construction and potential overheating of dwellings? The concept of thermal mass is still an area of construction where there remains no single response, as it may play a different role in different building types. The orientation of a building, solar control, effective ventilation and thermally efficient structures combined with elements containing thermal mass all contribute to a cost-effective, comfortable and sustainable solution. In housing, solar gain and airtightness should be considered as more significant than thermal mass. However, given that KLH panels are solid timber constructions (which are then externally insulated resulting in an external wall of approx. 50kg/m2) they have significantly higher properties of storage mass compared to traditional timber frame; with considerable improvements in the prevention of summer overheating. In effect, a cross-laminated timber superstructure should be classed as a middleweight, rather than lightweight structure.

6 What are the achievable u-values when building with KLH timber As a guide the table below shows the required u-values per element in the UK for some standard thicknesses: KLH Panel - 94mm Required thickness (in mm) of insulation dependent on its thermal conductivity (lambda in W/m*K) Area Element Required U-Values W/m2*K England, Wall Wales and Floor N. Ireland Roof Scotland Wall Floor Roof KLH Panel - 128mm Required thickness (in mm) of insulation dependent on its thermal conductivity (lambda in W/m*K) Area Element Required U-Values W/m2*K England, Wall Wales and Floor N. Ireland Roof Scotland Wall Floor Roof KLH Panel - 140mm Required thickness (in mm) of insulation dependent on its thermal conductivity (lambda in W/m*K) Area Element Required U-Values W/m2*K England, Wall Wales and Floor N. Ireland Roof Scotland Wall Floor Roof * blue marked figures can be reduced by 5mm if a plasterboard (12.5mm) is applied on inner surface.

7 Are KLH external timber walls insulated? KLH's external walls are not factory insulated, our preferred method of insulation is the layered strategy, which provides the simplest and most robust way to avoid air leakages, condensation issues etc. and guarantees a superb building performance. KLH's external wall panels require insulation, but compared with other building materials such as concrete (thermal conductivity l= ca. 1.8 W/m*k) or bricks, the insulation performance of timber (l= ca W/m*k) is naturally excellent. The tables on the previous page shows the minimum thickness of insulation needed to meet the requirements of UK standards. The minimum U-values are listed as well as the specified thermal conductivity of the insulation material that might be used. U-values are given by the Approvide Document L1A (British Building Regulations). The figures below assume that it is a wall build up consisting of a KLH panel and an external layer of insulation. What technical approvals do KLH timber panels have? KLH UK has 3rd party technical certification and accreditations for the KLH solid timber panels including: Full European Technical Approval (ETA 06/138) KLH's European Technical Approval is due to be amended in Spring 2010 to include an extended life span (more than 60 years) and enhanced performance under earthquake conditions. BRE Durability Report 60 year lifespan NHBC has provided a warranty for the Stadthaus, Murray Grove project and has stated that it is the first pilot residential scheme constructed entirely from cross laminated timber panels from the first floor upwards. Subsequent schemes will be assessed on a case by case basis. 0.4 TRANSPORTATION, DELIVERY AND ON-SITE MANAGEMENT What size of panels can be transported to the UK? The maximum standard dimension of a KLH panel are 16.5m length by 2.95m width, but we try to limit the maximum length to 13.5m in the UK because it is the most economical way of transporting the panels. 16.5m long panels can be transported on special vehicles, but this add additional cost to the original quote. How do you transport the timber KLH has a fleet of 15 lorries and employs a number of transportation companies to transport our panels from the factory in Austria and deliver them directly to the construction site in a fully enclosed 'megatrailer'. The use of megatrailers means that the panels are not susceptible to adverse weather during transportation. Panels arrive on site in the grade of controlled quality in which they left the plant, in Austria. How are the panel deliveries scheduled? The deliveries are scheduled on a 'just-in-time' basis to avoid unnecessary storage on-site. Storage will always be reduced to a minimum to avoid double-handling of panels. To optimise procedures we endeavour to erect directly from the delivery vehicle. Where storage is required, panels must be stored raised off the ground and carefully wrapped with polythene. Maximum on-site storage is usually 2 3 days (generally over a weekend). Can KLH UK deliver panels to any site? No, in order to deliver KLH panels to a site, there needs to be the facility to drive a mega trailer directly on to the site (dimensions are: 13.50m long by 2.95m wide) Panels can not be cut to a smaller size to fit them on to a smaller lorry for delivery to a site.

8 Is the KLH erection process integrated into the overall cosntruction programme? Yes, it is, we carefully programme the erection process on all KLH UK projects. We work with the main contractor to integrate our erection period into the overall construction programme. Is there a KLH site manager on-site during the erection of the timber structure? Yes, a minimum of one KLH Site Manager supervises the onsite erection of the structure and all our operatives are CSCS registered. We employ a specialist team of highly skilled carpenters to erect the building under the supervision of our Site Manager. Do KLH organise the cranes on-site and is it included in the quotation? Yes, we do organise the cranes for the erection of the timber panels and we include the costs in our quotations. We do not include the cost of traffic management in our quotations, as the need for traffic management is dependent on the site location, size of project and timescales for erection. Is the cost of scaffolding included in the quotation? The cost of scaffolding is not included in the quotation, but the cost of mobile access platforms (MAPS) and mobile scaffolding towers are include in the basic erection price.. The cost of the MAPS can not be removed from the quotations, as they are essential to the construction process. Is a method statement written for the on-site erection process? Yes, a method statement is created once the element drawings have been produced, as this allows KLH to identify the panels for sequential erection (plus 3D model of the scheme if required). However, a general approach to the construction is: Crane set-up on site specification as per details submitted to the contractor. 1st delivery arrives on site; subsequent deliveries arrive on a daily basis. General erection of process of walls floor walls roof. Can the building be erected in shorter timescales, if required? Yes, the erection process can take place over shorter timescales, but this would require additional teams on site during the erection of the structure, and is only possible if two cranes can operate on the site simultaneously. There would of course be additional costs to those originally quoted. After installation is the roof water tight? No, after installation the roof can not be consdiered water tight, it should receive a watertight covering ASAP. What does the method statement contain risk assessment? Yes the method statement contains risk assessments for Health & Safety purposes. The main areas that are considered are: Working at height of major note is EasiEdge (EE) protection. All work at the EE will be via mobile tower OR in cases where this is not feasible, and only then, operatives will be fixed to inertia reel block, which is attached to fixed point (Wurth Assy Kombi II capacity 1.3 Tonnes minimum) Temporary Bracing wall panels will be braced with a Wurth Brace (Montagestutze), max 22kN Acro-props will be used for temporary bracing of roof / ceiling plates External scaffolding will not be required for KLH erection Within KLH programme of works there should be no interface with other trades (unless scaffolding operatives commence external works whilst KLH programme is still in progress) KLH UK and the safety equipment manufacturer EasiEdge work together to develop new systems that virtually eliminate the need for scaffolding and mean that edge protection can be pre-fitted to the timber panels at ground level. Do KLH UK undertake post assembly inspections? KLH undertake a post assembly review with the main contractor on every project. A report is compiled from the review including a snagging list of activities that need to be undertaken before the building can be signed off and handed over for the next stage of the construction or fit out work.

9 0.5 CONTACT US If you have any other questions that are not covered in this document, please contact us at: KLH UK 7-9 Woodbridge Street London EC1R 0LL t: +44 (0) f: +44 (0) e: