Onduline Oversheeting Benefits Low cost. The Onduline colour range Reduced health risk in handling and disposing of existing hazardous roof coverings. Virtually maintenance-free. Improved thermal and sound insulation. Reduced risk of condensation. Simple and quick installation. Onduline has BBA Certification. 15-year insurance-backed weather-proof guarantee. BLACK BROWN GREEN RED These colours are for guidance only Onduline Sheet Specification Cost comparison A demonstration of the cost-effectiveness of the Onduline Oversheet System For the price of the Onduline Oversheet System fixed on a 100m 2 duo pitch roof you will cover only 68% of the roof with fibre cement and only 78% using an equivalent quality steel sheet. Onduline 100% fibre cement 68% steel sheet 78% Table of size, weight and thickness. Length and width of sheet 2000 x 950mm Nominal coverage/sheet (roof pitches over 15 ) 1.55m 2 Number of fixings per sheet 10 to 15 25 15 and over 20 Nominal thickness Corrugation height 3mm 38mm Insulation Corrugation width 95mm Nominal material weight 3.3 kg/m 2 The Onduline Oversheet System allows the thermal properties of the roof to be easily upgraded. This can be achieved by laying a suitable insulation material between the Onduline support battens. An Ondutiss vapour barrier should be fixed below the insulation and ventilation provided above the insulation. For metal roof applications, insulation should be incorporated to avoid problems created by the transfer of solar heat into the roof space of the building. Fig.3 Nominal weight/sheet 6.4 kg Insulation material Vapour barrier membrane Fig.3
Maintenance To ensure a long, trouble-free life, the roof should be cleared of leaves and debris on a regular basis, and gutters should be kept clear. Rooflights The Onduline Oversheeting System can be easily modified to provide illumination over existing glazed roof lights. However, the requirements of HSE HSG 33 Health and Safety in Roof Work Guidance must be incorporated. Contact our technical department for further information. Supply Onduline is readily available from stock through authorised distributors. A complete list can be obtained on application. For bulk delivery please contact Onduline direct. Installation and price list A detailed installation guide and price lists are available, and can be obtained from Onduline. Onduline Oversheeting in action Technical services A comprehensive technical advisory service with laboratory testing facilities is available for all Onduline applications. Conditions of use Although the process of colour impregnation for Onduline products is long lasting, weathering effects cannot be entirely discounted. Onduline will be affected in the same way as similar natural roofing materials. Onduline International will not be responsible for the effects of structural movement. The information contained in this brochure is correct at the time of printing but the manufacturers reserve the right to vary specifications and details at any time. To avoid any possible misunderstanding, customers seeking advice on either the suitability or the performance of goods or on the nature of the services provided, should put their requirements in writing. Goods are not tested or sold as fit for any particular purpose unless it has been agreed in writing. There may be a slight variation in the size and weight of each sheet. The Onduline product range Onduline roofing sheets Ondutile roof underlay system Ondusteel profiled steel tile strip Bardoline bituminous tile strip Bituline torch-on membranes Fondaline damp-proofing membranes Onduline plastics - PVC and polycarbonate roofing sheets For details contact our technical sales department NF ISO 9002 ONDULINE PRODUCTION SARL FRANCE Uni en ISO 9002 ONDULINE ITALIA SPA MS ISO 9002 ONDULINE BUILDING MATERIALS MALASYIA Onduline Building Products Limited Eardley House, 182-184 Campden Hill Road, Kensington, London W8 7AS Tel: 020 7727 0533 Fax: 020 7792 1390 E-mail: ondulineuk@aol.com A member of the international Onduline Group Factories in - Belgium, France, Italy, Malaysia, Poland, Spain, Turkey. Offices in - Belgium, Brazil, Bulgaria, Czech & Slovak Federal Republics, England, France, Germany, Greece, Holland, Hong Kong, Hungary, Italy, Malaysia, Poland, Portugal, Romania, Russia, South Africa, Spain and Ukraine. BBA BRITISH BOARD OF AGREMENT CERTIFICATE NO. 87 / 1823 / C Certificate No 40381 Issued 26 April 1997 Authorised Distributor: Registration No IT1482 CISQ/CERTICHIM No. 862 Issued 24 February 1997 Registration No AR1061 Serial No 0224 Avis technique CSTB No. 5/96-1198 0700/TW/10,000 (317) Designed & produced by The Works (44) 01603 761500
CI SfB (4--) Nn2 OVERSHEET SYSTEM FOR FAST, ECONOMIC AND RELIABLE OVERSHEETING OF OLD CORRUGATED ROOFS BBA BRITISH BOARD OF AGREMENT CERTIFICATE NO. 87 / 1823 / C
Oversheeting Roof covering renewal the case for oversheeting. Faced with the problem of renewing an old, deteriorating corrugated roof, there are two options available to remove and replace the old roof covering, or to oversheet. Before you decide, you will need to take account of a number of design, cost and environmental considerations such as:- Disruption caused to the interior of the building during re-roofing. Choice of replacement roofing materials to be used. The complexity of the roof including protrusions such as roof lights, soil and flue pipes etc. Matching the fixing and spanning characteristics of the new roof covering to the existing roof structure. Ability of existing roof structure to take the additional weight involved in oversheeting. Upgrading of thermal and sound insulation. Health risk in handling and disposal of existing hazardous roofing materials (particularly asbestos), in accordance with Health and Safety Regulations. Economics. Provision of roof underlining. The use of the Onduline Oversheet System in the majority of cases satisfies these design considerations, demonstrating significant benefits over replacement, in terms of both economic and practical design criteria. Onduline Oversheet System The Onduline Oversheet System has been developed with the benefit of our extensive world-wide experience. It is an adaptable system that is ideally suited to a wide variety of roof construction types. The system utilises Onduline corrugated roofing sheets, developed for over 50 years and now sold in over 90 countries world-wide. Onduline provides an extremely tough, flexible, lightweight roof covering that is virtually indestructible but very easy to fix, even to curved roofs. All this together with its comparatively low cost combine to make Onduline the ideal oversheeting material. Onduline is made by saturating organic fibres with bitumen under intense pressure and heat. It contains no asbestos and presents no health hazard. Onduline is available in four attractive colours, with colour stability ensured by a unique pigmentation process which stains the colour into the sheet. Onduline is covered by a 15 year insurance-backed weatherproof guarantee. It also has BBA product certification. Onduline roofing sheet Eaves detail to suit eaves finish option Onduline support batten fixed to main batten Main support batten fixed through sheet to existing purlin Existing corrugated sheet roof finish Existing purlin
Fixing Schedules Timber fixing schedule Main batten Fixed from eaves to ridge at centres or on exposed sites at 450mm centres. Batten size in accordance with the following table; Roof sheet type Main batten (mm) Standard 6 fibre-cement 75 x 50 or 50 x 50 Standard 3 fibre-cement 50 x 38 or 50 x 50 Profiled galvanised or plastic coated steel or iron 50 x 38 or 50 x 50 Onduline support battens. Fixed verge to verge. Roof pitches over 15 Roof pitches 10 to 15 Batten size Mechanical fixings schedule centres 450mm centres 25 x 38mm or 50 x 50mm Fixing main battens to existing roof purlins. Fixing to existing timber purlins. Annular ring shank nails 125 x 3.35mm or 75 x 3.35mm Wood screws 125mm x 10g Fixing to existing steel purlins. Galvanised J-type bolts, self tapping or self drilling screws. Size and type to suit existing purlin type. Fixing Onduline support batten to main batten. Annular ring shank nails 65 x 3.35mm. Fixing Onduline sheets to support batten. Onduline PE nails or Onduline Safe Top heavy duty nails. Fixing Onduline sheets to steel batten. Stelfix drill screws. Self Tapping Self Drilling 950mm maximum maximum maximum 2000mm Annular J-type Stelfix Schedule of components Component options - subject to design requirements: Onduline ridge piece 900mm length Onduline verge piece 1100mm length (125mm end lap used for ridge and verge pieces) Ventilator strip 1000mm length Onduline eaves filler 846mm length Eaves tray 1275mm length (150mm end lap) Insulation material to suit thermal design requirements. Installation notes These installation notes are for general guidance only in fixing Onduline material. For special applications or variations in roof form, please contact our technical department for assistance. Caution Covering existing fragile corrugated roofs is a specialist operation. All works should be carried out with due regard to all Health and Safety Regulations; this is of particular importance when dealing with fibre cement materials possibly containing asbestos. Under no circumstances should blue and brown asbestos be oversheeted and on any roof containing old asbestos consult your Environmental Health Officer for guidance and follow relevant site handling requirements. It is advisable not to clean corrugated fibre cement sheets. Treat them with a dilute PVA adhesive coating to consolidate the internal and external surfaces prior to fixing. Finally lay Ondutiss roofing membrane onto main support battens to seal roof. Building Regulations should be adhered to and in some instances planning approval may be required. Preparation A thorough inspection of the existing roof structure should be undertaken, any deterioration should be rectified and the structure checked as to its suitability for oversheeting procedures. A review of the original roof design should be made to check that sufficient ventilation and insulation is provided, and if necessary, alterations incorporated in the Onduline Oversheet System refurbishment. Fire resistance All statutory requirements should be adhered to in accordance with relevant British Standards and Codes of Practice. Consult our technical department if specific project information is required. Fixing procedure Fixing the main support battens Select the correct section of timber to suit existing sheet corrugation size in accordance with timber schedule, and fix from eaves to ridge through the existing roof covering in accordance with fixing schedule. Note: 1 Allowance should be made for additional space required for provision of insulation. 2 Fragile roofs will require pre-drilling. 3 All battens must be treated. 4 If asbestos is expected in the roof, overlay main support battens with Ondutiss membrane. Fixing the Onduline support battens Overlay and fix the main battens with the Onduline support battens, verge to verge, at 450 or centres in accordance with the Onduline timber fixing schedule. Note: Eaves tray and ridge component require additional support battens. Fixing the Onduline sheets The Onduline sheets are fixed in accordance with the Onduline fixing handbook. Care should be taken to ensure that the fixing penetrates the batten centrally. Insulation option Ondutiss vapour check membrane is laid up the roof from verge to verge over the main support battens with l00mm side and end laps. The Ondutiss is overlaid with the Onduline support battens. The insulation is laid between the support battens. The Onduline sheet can then be fixed. Note: Ventilation must be provided below the Onduline sheet.
Construction Notes FIG.1 Standard eaves fixing The overhang of the existing corrugated sheet is trimmed back in line with the fascia. A new raised fascia is fixed to the height of the top edge of the Onduline support battens. The rainwater goods are re-fitted. The Onduline sheet is then laid with a maximum of 70mm overhang at the eaves. A ventilator strip is fixed to eaves batten. Fig.1 FIG.2 Flush eaves fixing The flush eaves detail avoids cutting the existing corrugated sheet or repositioning the rainwater goods. A ventilator strip is fixed to the eaves batten sealing the existing roof corrugations; this is overlaid with an eaves tray, its rear edge supported by a secondary batten. Onduline sheet is laid with a maximum of 25mm overhang from the front edge of the eaves tray. Fig.2 FIG.3 Eaves spa brackets fixing An alternative method of avoiding the cutting of the existing corrugated material is to use spa fixing brackets fixed to the main support battens, allowing the rainwater goods to be easily re-positioned. FIG.4 Verge detail The verge is formed by using the preformed Onduline verge section, or by forming a verge cloaking piece from zinc or similar flashing material. Fig.3 FIG.5 Ridge detail In most cases the existing ridge units can be retained. In these situations the top of the main batten may need to be chamfered to suit the raised ridge line. Onduline preformed ridge pieces can then be fixed utilising an additional support batten as shown. Fig.4 FIG.6 Steel fixing detail Steel oversheeting support structures can be fabricated following the same basic principles applied to timber structures. Galvanised steel multibeam rails are fixed from eaves to ridge with drill screws through the roof covering into the existing purlins. These are then overlaid with steel Z section purlins at centres to which the Onduline sheets are fixed using the Onduline Stelfix drill screw. Fig.5 Fixing of Onduline sheets should be carried out in accordance with the Onduline Fixing Guide available from our technical department. Fig.6