Prefabricated elements

Prefabricated elements Training presentation

Contents Product description Application in buildings Certification References

Product description Back to contents page

Prefabricated elements – product description • The Prefabricated wall element is an external wall system, where galvanized (hot-dip zinc-coated) thermo purlins act as the wall’s frame structure. Perforation in the purlin’s web significantly decreases thermal conduction through the purlin • In demanding projects, a highly prefabricated element system based on advanced and standard solutions speeds up on-site construction

Prefabricated elements – product description • The element system consists of thermo purlins, windshield plasterboards, thermal insulation, vapour barrier, fixings, seals and external cladding • Wall elements´ façade cladding can be made of steel, wood, brick, aluminium, copper, glass, plaster, stone or ceramic tiles

Prefabricated elements – product description • When using thermo purlins, external walls can be built with Prefabricated wall elements that are assembled at the factory • The element system is based on the products of Ruukki’s automatic purlin manufacturing line, which enable increased element accuracy, straightness and levelness, thanks to the innovative narrowing and countersink joint technology applied to the purlins • The designing of elements is done with advanced NorTS software that simultaneously produces a transfer file for the automatic Termopurlin manufacturing line, as well as the material lists and element drawings needed for production purposes

Prefabricated elements – structure • External façade options: • Steel or other metals, wood, glass, natural stone, brick, ventilated thin rendering, insulated rendering, ceramic tiles • Windshield: • Gypsum sheathing board, 9 mm (TS 9), porous wood fibre sheathing board, e.g. 12 mm or 25 mm, plywood, e.g. 6,5 mm or 9 mm, bitulite, e.g. 12 mm, cement bonded particle board, 4 mm or 8 mm • Thermo purlin structure: • The steel grade, S350GD+Z275 • The amount of zinc is 275 g/m² • Thermo purlin come in LPT-U, LPT-C and LPT-Z profiles. The most commonly used profiles are LPT-C and LPT-U in 175 and 200 mm widths • The thickness options are 1, 1.2, 1.5 and 2 mm

Prefabricated elements – structure • Thermal insulation: • Incombustible, design thermal conductivity λ Design = 0,035/0,037 W/m²K (windshield board panel joints are sealed and both sides of the insulation are in contact with insulated surfaces) • Plasterboards: • Interior wall cladding is made of 13-mm tapered plasterboard or galvanized steel sheets. Wind protection is in many cases provided with 9 mm windshield plasterboard. Other materials may also be used as long as they conform with the manufacturer’s instructions • Hardened gypsum board, 13 mm (EK13), thin steel sheet 0,6–1,0 mm + hardened gypsum board 13 mm, wood-gypsum board, e.g. 10 mm or 12 mm, chipboard, e.g. 10 mm, 11 mm or 12 mm, plywood, e.g. 9 mm or 12 mm, semi-hard wood fibre board, e.g. 9 mm, thin steel sheet 1,5 mm

Prefabricated elements – structure • Fixings: • Zinc-coated drill screws and pierce rivets. Plasterboards are fitted with drill screws suitable for the particular plasterboard types • Vapour barrier: • LDPE (Low-Density Polyethylene) plastic 0.2 mm, compliant with the SFS 4225 standard, Class E, UV protected • Water vapour permeability value Wp = 0,002*10-9 kg/(m2sPa) • Water vapour diffusion resistance Zp = 500*109 m2sPa/kg

Prefabricated elements – structure 8-perforated rows • 1. External façade • 2. Ventilation channel 20 mm • (Purlins, e.g. Support stud CA1SS) • 3. Windshield board • 4. Thermal insulation + termo stud • 5. Vapour barrier • 6. Internal lining Studs, C/C 600

Prefabricated elements – standard element types • Square elements are usually elements about one storey high, beginning from one level and extending to the next level. The element length is usually in accord with the frame module • The most typical applications of square elements are office buildings and multi-storey residential buildings with storey heights of up to 3,600 mm • Square element max. 3600 x 10500 mm

Prefabricated elements – standard element types • Strip elements are elements situated between rows of band windows, normally extending from column to column • The most typical strip element applications are office buildings • Strip element max. 3600 x 10500 mm²

Prefabricated elements – standard element types • Turn over elements are narrow, high elements which, due to their dimensions, are transported on their side. Turn over elements can be one or two storeys high • They are often used as the top storey's element in square element applications, in which case they include an extension for the eaves • Turn over elements are also typically used in constructing the walls of business premises with high ceilings

Prefabricated elements – standard element types • Horizontal elements differ from other element types in that the element purlins are positioned horizontally. They are used in constructing industrial buildings • These elements are commonly called Industrial wall elements • Horizontal element max. 3600 x 10500 mm

Prefabricated elements – standard element types • Normally, transportation constraints limit the maximum element height at 3,600 mm. The use of higher elements can be agreed on exceptional projects • The element length is normally around 8 m, but even 12 m long elements can be made in special cases

Thermal conductivity, U-values

Sound insulation • Structures from inside outwards • *) Calculated value • Rw (dB) = Airborne sound insulation value • RA,tr (=Rw+Ctr) (dB) = Traffic noise sound insulation value

Fire resistance • Test standard: EN 1363-1 EN 1365-1 • Classification standard: EN 135 01-2 • In load bearing wall situations structures can also meet REI30 and REI60 in accordance with separate instructions. • R = resistance, E = integrity, I = insulation • In fire structures, Rockwool should be used as thermal insulation, e.g. Paroc eXtra.

Application and advantages Back to contents page

Prefabricated elements – advantages • Excellent acoustic characteristics • Sound insulation • Possible to tailor unique acoustic solutions, case by case • Excellent thermal insulation characteristics • Even very heavy objects can be installed to external wall surface (e.g. decoration) • Large variety of cladding materials • Variously shaped external wall quickly and cost-effectively

Prefabricated elements – advantages • Reduces on-site building time • Lower risk for bad quality (e.g. damaged vapour barrier or moisture problems), thanks to advanced factory production • Increased element accuracy, straightness and levelness, thanks to the innovative narrowing and countersink joint technology applied to the purlins

Prefabricated elements – applications • Office and commercial buildings • Public buildings • Industrial buildings • Residential buildings • Building extensions and renovation • Shopping centers • Sports buildings • Halls • Agricultural construction

CE-Marking Back to contents page

Prefabricated elements: CE marking • CE marking was started 5th December 2005 as a first CE marking in Ruukki Construction • It is according to EN 13830 and for non-load bearing elements • Elements have gone through ITT (Initial Type Testing), where several properties of the element have been tested and checked to be according to standard, like • air permeability • water tightness • fire properties

Prefabricated elements: CE marking • Elements have also FPC (Factory Production Control), where is specified what kind of measurements are taken in manufacturing phase and what are the accepted tolerances • The most visible documents to our clients about the CE marking are label on the product and Declaration of Conformity

References Back to contents page

References • Shopping centre Kamppi in Helsinki, Finland

References • Panorama Tower in Espoo, Finland

References • Technology centre Technopolis in Vantaa, Finland

References • The new headquarters of Varma Mutual Pension Insurance Company are located in Salmisaari, Helsinki, Finland

References • Varma Mutual Pension Insurance Company in Salmisaari, Helsinki, Finland

Thank you for your interest

Prefabricated elements