BS-8219-2001.pdf

BRITISH STANDARDBS 8219:2001 Installation of sheet roof and wall coverings Profiled fibre cement Code of practice ICS 91.060.10; 91.060.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 This British Standard, having been prepared under the direction of the Sector Policy and Strategy Committee for Building and Civil Engineering, was published under the authority of the Standards Policy and Strategy Committee and comes into effect on 2 October 2001 © BSI 2 October 2001 The following BSI references relate to the work on this standard: Committee reference B/542/4 Draft for comment 00/101868 DC ISBN 0 580 38538 8 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee B/542, Roofing and cladding products for discontinuous laying, to Subcommittee B/542/4, Fibre reinforced cement sheeting for roofing, upon which the following bodies were represented: Association of Building Component Manufacturers Association of Building Engineers Consumer Policy Committee of BSI Department of the Environment, Transport and the Regions (British Board of Agrément) Department of the Environment, Transport and the Regions Building Research Establishment (BRE) Fibre Cement Manufacturers Association Ltd. Glassfibre Reinforcement Cement Association National Federation of Roofing Contractors Amendments issued since publication Amd. NoDateComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 © BSI 2 October 2001 i Contents Page Committees responsibleInside front cover Forewordii 1Scope1 2Normative references1 3Terms and definitions1 4Classification2 5Checking, handling and working, site storage of materials and preparation2 6Installation of sheets4 7Safety and general precautions14 Bibliography15 Figure 1 Mitring guide5 Figure 2 Method for checking tightness of fastener6 Figure 3 Exposure to wind driven rain8 Figure 4 Lap seal positions10 Table 1 Acceptance characteristics (BS EN 494:1994, Table 5)2 Table 2 Sheltered and moderate exposure sites (less than 56.5 l/m2 per spell)9 Table 3 Moderate and severe exposure sites (greater than or equal to 56.5 l/m2 per spell)9 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 ii© BSI 2 October 2001 Foreword This British Standard has been prepared by Technical Committee B/542/4. It supersedes BS 5247-14:1975, which is withdrawn. This code of practice takes into account the change to non asbestos reinforced fibre cement profiled sheets and accessories together with the introduction of proprietary self-drilling fastener systems. It has been assumed in the preparation of this code of practice that the execution of its provisions is entrusted to appropriately experienced and competent people, that the design of external sheet roof and wall coverings is entrusted to suitably qualified designers and that installation is carried out by competent operatives and supervisors. Acknowledgement is given to Eternit Building Materials for permission to use the drawings in this code of practice and to the National Federation of Roofing Contractors (NFRC) for permission to reproduce them from Profiled sheet roofing and cladding A guide to good practice 1. As a code of practice this British Standard takes the form of guidance and recommendations. It should not be quoted as if it were a specification and particular care should be taken to ensure that claims of compliance are not misleading. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Attention is drawn to the following statutory regulations: Control of Substances Hazardous to Health (COSHH) Regulations 1994 2, Lifting Operations and Lifting Equipment Regulations 1998 3, Health and Safety at Work etc. Act 1974 4, Special Waste Regulations 1996 5, and the Construction (Design and Management) Regulations 1994 6. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 15 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 © BSI 2 October 2001 1 1 Scope This British Standard code of practice gives recommendations for basic workmanship and tasks carried out in relation to the installation of profiled fibre cement sheets for roofing and external wall cladding including associated fittings and accessories. This code of practice also gives recommendations for design specific to the use of profiled fibre cement sheets for roof and wall cladding on buildings. NOTE 1For design aspects of profiled fibre cement sheeting reference should be made to BS 5427-1. NOTE 2This code of practice makes no reference to asbestos cement. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this British Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. For undated references, the latest edition of the publication referred to applies. BS 5427-1:1996, Code of practice for the use of profiled sheet for roof and wall cladding on buildings Part 1: Design. BS 6100-1.3.2, Glossary of building and civil engineering terms Part 1: General and miscellaneous Section 1.3: Parts of construction works Subsection 1.3.2: Roofs and roofing. BS 6399-1, Loading for buildings Part 1: Code of practice for dead and imposed loads. BS 6399-2, Loading for buildings Part 2: Code of practice for wind loads. BS 6399-3, Loading for buildings Part 3: Code of practice for imposed roof loads. BS EN 494:1994, Fibre-cement profiled sheets and fittings for roofing Product specification and test methods. 3 Terms and definitions For the purposes of this British Standard the terms and definitions given in BS 6100-1.3.2 and the following apply. 3.1 cladding assembly roof or wall covering system, which may be a site assembly of liner, spacer and profiled sheeting elements together with insulation and vapour control layers 3.2 profiled sheet sheet, longitudinally formed, with regularly spaced shapes or sinusoidal cross-sections, which can support load over a span 3.3 short sheet sheet having a length less than or equal to 0.9 m 3.4 long sheet sheet having a length greater than 0.9 m 3.5 primary fastener fastener that secures profiled sheeting and/or lining to the supporting structure sheeting to purlin or spacer, or spacer to purlin Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 2© BSI 2 October 2001 3.6 secondary fastener fastener that secures the side laps of translucent sheets to side laps of profiled sheets but not to the supporting structure and which is used to attach accessories such as flashings to sheets 3.7 fibre cement cement reinforced with natural or man-made fibres excluding reinforcement by asbestos fibres 3.8 lap amount one sheet overlaps another at either the end (end lap) or the side (side lap) 3.9 pitch degree to which the roof covering slopes from the horizontal 4 Classification Fibre reinforced profiled sheets should be classified in accordance with BS EN 494. The characteristics of profile shapes and longitudinal and cross breaking strengths should be in accordance with Table 1. Table 1 Acceptance characteristics (BS EN 494:1994, Table 5) Class 1 sheets are recommended, as breaking load levels are similar to asbestos fibre reinforced sheet strengths, that have proven experience in the UK. 5 Checking, handling and working, site storage of materials and preparation 5.1 Checking 5.1.1 Delivery note Delivery notes and any certificates of quality and origin should be checked together with product identification marks and/or labels before materials are accepted on site. 5.1.2 Condition The quantities and condition of all products, fittings and accessories should be checked. If they are not satisfactory the supplier should be contacted immediately. No unsatisfactory products, fittings and accessories should be used. 5.1.3 Painted sheets Painted sheets and fittings should be checked to ensure that they have been painted to the colour as ordered. CategoryHeight of corrugations Long sheetsShort sheets Minimum thickness Breaking loadBending moment at rupture Minimum thickness Bending movement at rupture Class 1Class 2Class XClass Y mmmmN/mN/mN m/mN m/mmmN?m/m A15 to 304.01 4001 25040303.525 B25 to 455.02 5002 00055404.030 C40 to 805.24 2503 50055404.030 D60 to 1205.57 0005 50055455.040 E90 to 1506.012 5008 5005545 NOTEA special class 3 with a minimum breaking load per metre width of 2 200 N/m in category C for sheets of length greater than 0.90 m and less than 1.25 m is also available. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 © BSI 2 October 2001 3 5.2 Handling and working 5.2.1 General Reference should be made to the manufacturers Health and Safety Data sheets produced in accordance with the Control of Substances Hazardous to Health (COSHH) Regulations 1994 2. 5.2.2 Lifting NOTEConsideration at all times should be given to current Lifting Regulations covered in the scope of the Lifting Operations and Lifting Equipment Regulations 1998 3. Safe handling of fibre cement sheets on a roof may require two or more people in certain circumstances. Sheets should be lifted by their ends only. Two people should lay sheets at the eaves and around rooflights. 5.2.3 Cutting Sheets should be cut at ground level only on suitable rigid supports with a hand saw or slow speed reciprocating power saw. Disc or circular blade devices should not be used. 5.2.4 Dust Dust generated when working with fibre cement should not require any special handling requirements other than normal housekeeping to maintain a clean working area. The dust is classed as a nuisance dust. When using power tools, dust collection equipment should be considered. 5.3 Site storage 5.3.1 Natural grey sheets 5.3.1.1 Natural grey profiled fibre cement sheets for use should be stored as close as practicably possible to the area of works. Prior to use, the sheet stacks should be stored so that they are clear of traffic and other site operations. Care should be taken to protect them from dirt and damage. 5.3.1.2 The sheets should always be stacked on a firm, preferably concrete, level base with a minimum of three timber bearers (75 mm ? 75 mm) to keep them off the ground. Sheet stacks should be of a maximum height of 1500 mm. 5.3.1.3 Where stacks of sheets have been delivered wrapped in shrink wrapped polythene this should be retained as long as possible to control the environment around the sheets. 5.3.1.4 Unused and partially used stacks should be protected from the weather by extending the top sheets 200 mm at each end. The stacks should be tied or weighted down to prevent damage in high winds. 5.3.1.5 Sheets of the same length should be kept together, but in the event that this is not possible the longest sheets should be located at the bottom and the shortest at the top of the stack. 5.3.1.6 Some sheets have either a large overlay roll or small underlay roll along each long edge. At all times the large rolls should be stacked on the large rolls and the small rolls should be stacked on the small rolls. 5.3.1.7 All sheets should be stored “weather” or smooth side upwards. 5.3.2 Painted sheets 5.3.2.1 Painted fibre cement sheets should be stored in a similar manner to natural grey sheets (see 5.3.1) but should at all times be protected from the weather to reduce the risk from efflorescence staining. 5.3.2.2 If the stacks are delivered in shrink wrapped polythene, this should be removed. Protection should preferably be provided by storage inside a building. If this is not available, the sheets should be covered by a breathable tarpaulin ensuring that there is effective air circulation around the stack. The tarpaulin should be spaced off the top, sides and ends of the stack to avoid condensation. NOTEWhen natural grey or painted fibre cement sheets are to be installed on a building in which there will be higher than normal temperatures, e.g. foundries and kilns, the sheets should be stored near a heat source prior to fixing and then they should only be fixed on a dry day. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:02:23 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8219:2001 4© BSI 2 October 2001 5.4 Checking the structure 5.4.1 Before sheeting commences an appropriately experienced individual should check that all purlins and rails are securely connected (see Foreword). Measurements should be taken to ensure the structure, purlins and rails are true and level to receive the sheeting. 5.4.2 In particular, a check should be made that the purlins and rails are spaced correctly for the correct end lap and that the eaves purlin provides an appropriate unsupported overhang. 5.5 Preparation of work 5.5.1 The structure should be adequately prepared for sheets in accordance with 5.4. NOTEHealth and safety provisions in accordance with current regulations 4 should be followed. 5.5.2 When the sheeting layout is being planned, care should be taken to ensure that the verge sheets are cut so that the outside edge coincides with a crown rather than a trough in corrugations. NOTEThis enhances the weather protection unless a barge board is used. 5.5.3 Sufficient overhangs should be allowed at the eaves to ensure that rainwater discharges into a gutter. Typically the overhang into a gutter should be 12 mm behind the centre line of half round gutters and 100 mm beyond the inside edge of larger industrial gutters. 6 Installation of sheets 6.1 Sequence of installation 6.1.1 It is essential that fibre cement sheeting is installed correctly in order to avoid leaks, corrosion of fasteners or premature failure in the completed roof. 6.1.2 Unless otherwise specified, all sheets should be installed “weather” or smooth side outwards. 6.1.3 All fastener holes should be drilled, not punched, and provide an adequate clearance hole for the fastener shank of a minimum dimension of 2 mm greater