Sommerhein AB Box 1089 S Lidingö SWEDEN Tel: Fax: website:

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1 Sommerhein AB Box 1089 S Lidingö SWEDEN Tel: Fax: per@sommerhein.com website: CI/SfB (52) X Agrément Certificate No 95/3179 Designated by Government to issue European Technical Approvals Product THIS CERTIFICATE RELATES TO THE UV-SYSTEM FOR FULL BORE FLOW ROOF DRAINAGE COMPONENTS AND THE UV-SYSTEM SOFTWARE USED IN DESIGN. THE PRODUCTS ARE FOR USE WITH CONVENTIONAL PRESSURE RATED PIPE SYSTEMS. The system is for use in installations designed in accordance with BS 5572 : 1994 and/or BS 6367 : 1983 for the conveyance of surface water as is permitted to be discharged into public sewers by The Water Industry Act 1991 Chapter 56 and surface water as is permitted and defined by the Sewerage (Scotland) Act 1968 and the Water and Sewerage Services (Northern Ireland) Order At the design rainfall intensity, installations designed using UV-System software and installed with UV-System outlets in accordance with this Certificate will ensure that the outlets eliminate the intake of air into the system. This sets up full bore flow and maximises the capacity of the pipework. It is essential that systems are installed precisely in accordance with the computed design. Collecting pipes are installed horizontally under the roof, reducing the number of downpipes and the associated underground work and drainage. Components of the system are used individually or in conjunction with conventional pressure-rated pipes and fittings which comply with the performance specification denoted in the UV-System Technical Manual. UV-SYSTEM FOR ROOF DRAINAGE UV-Système d évacuation des eaux pluviales par effet siphoïde UV-System für Dachentwässerung nach dem Vollstromprinzip Building Regulations 1 The Building Regulations 1991 (as amended 1994) (England and Wales) The Secretary of State has agreed with the British Board of Agrément the aspects of performance to be used by the BBA in assessing the compliance of drainage systems with the Building Regulations. In the opinion of the BBA, the UV-System for Roof Drainage, if used in accordance with the provisions of this Certificate, will meet the relevant requirements. Requirement: C4 Resistance to weather and ground moisture Requirement: H3 Rainwater drainage Requirement: Regulation 7 Materials and workmanship The joints between the roof outlet and the roof will adequately resist the passage of moisture to the inside of the building. See section 10 of this Certificate. The roof outlets will contribute to carrying the flow of rainwater from the roof to an outfall, thus minimising the risk of blockage or leakage. The system is acceptable. See section 17 of this Certificate. 2 The Building Standards (Scotland) Regulations 1990 (as amended) In the opinion of the BBA, the UV System for Roof Drainage, if used in accordance with the provisions of this Certificate, will satisfy or contribute to satisfying the various Regulations and related Technical Standards. Regulation: 10 Fitness of materials Standards: B2.1 and B2.2 Selection and use of materials and components The system is acceptable. Regulation: 17 Preparation of sites and resistance to moisture Standard: G3.1 Resistance to precipitation Regulation: 24 Drainage and sanitary facilities Standards: M2.1 Drainage system The system meets the relevant requirement of this Standard. The system will meet the requirement of this Technical Standard. 3 The Building Regulations (Northern Ireland) 1994 In the opinion of the BBA, the UV-System for Roof Drainage, if used in accordance with the provisions of this Certificate, will satisfy the various Building Regulations as listed below. Regulation: B2 Fitness of materials and workmanship Regulation: N7 Rain-water drainage Regulation: C5 Resistance to ground moisture and weather The system is acceptable. See section 17 of this Certificate. The system meets the relevant requirements of this Regulation. The system meets the relevant requirements of this Regulation. See section 10 of this Certificate. Readers are advised to check the validity of this Certificate by either referring to the Index of Current BBA Publications or contacting the BBA direct (Telephone Hotline ).

2 Technical Specification 4 Description 4.1 The UV-System for Roof Drainage consists of roof outlets, technical specifications and computer software to design the pipework for each installation. 4.2 UV-System roof outlets are available with plain spigots (53 mm or 69 mm internal diameter) or externally threaded spigots (2 BSP or 2½ BSP). The components and the respective material types are shown in Figure 1. Figure 1 air baffle retaining stud (2 no) clamp nut clamp stud orifice plate (optional) Roof outlet 4.3 Stainless steel orifice plates 104 mm diameter with holes 15 mm, 20 mm, 25 mm, 30 mm, 35 mm or 40 mm diameter are available to vary the hydraulic resistance of the roof outlet (for use on flat roofs only). 4.4 The outlets are for use with the pipes and fittings covered by the performance specification given in section 6 of this Certificate. Pipework should be independently certificated for compliance with the declared specification. 4.5 Suitable pipes and fittings are available in the following materials: cast iron stainless steel galvanized steel copper PVC-U PE ABS PP. 4.6 Factory production control is exercised during manufacture including checks for conformity to the specification of the raw materials, and checks on dimensions, thickness and visual appearance. Weld integrity of the studs and airtightness checks on the outlet bowl are carried out on each unit. leaf guard (aluminium alloy) air baffle (aluminium alloy) clamp ring (stainless steel) outlet bowl (stainless steel) outlet spigot (stainless steel) 5 Delivery and site handling Each outlet carries the product code, the manufacturer s logo and the BBA identification mark. The BBA identification mark including the number of this Certificate is incorporated in the company s technical literature. The products are delivered to site either on pallets or in single boxes depending on the quantity. Design Data 6 General 6.1 When designed, installed and used in accordance with the provisions of this Certificate the UV-System for Roof Drainage will convey rainwater from the roof to a below-ground drainage system. 6.2 Further advice on designing full bore flow roof drainage systems is given in the UV-System Technical Manual. 6.3 Gutters should be designed in accordance with BS 6367 : Pipes and fittings must meet the performance specification fully detailed in the UV-System Technical Manual. The key characteristics include: Pipework must withstand both positive and negative pressure equivalent to a 9 m head of water, ie 0.9 to 0.9 bar gauge pressure. Joints must be capable of either resisting longitudinal forces without sliding apart or must be restrained to prevent relative movement. Sharp radius bends in excess of 45º deviation from straight flow should not be used. Eccentric reducers are recommended for use in horizontal flows with the crown of the pipe level. 6.5 The underground drainage system must be capable of accepting without surcharge the rate of flow of water discharged by the UV-System in addition to other discharges which may be received. 7 System design and dimensioning 7.1 Each UV-System for Roof Drainage must be designed by a person trained to use UV-System computer software and familiar with hydraulic and roof drainage design procedures. 7.2 The system is designed to flow at maximum capacity when rainfall is at the design intensity. A system using the pipe dimensions obtained from the design will ensure sufficient capacity to transport the water from the roof to the discharge point. 7.3 Information required to enable a design to be carried out includes: (a) design rainfall intensity (normally selected or calculated from BS 6367 : 1983) 2

3 (b) geometric layout of the roof and outlets including the height of the building and its location and plan location (c) position of underground connection. 7.4 Use of the computer program ensures the most economic and effective design is achieved. Critical conditions to be achieved in any design include: (a) minimum water velocity must be 0.7 ms 1 at the design flow intensity to achieve a self-cleansing velocity (b) computed flow (1) from an individual outlet must not exceed the specified maximum for each outlet size (c) in systems with more than one roof outlet, the balance in the system should not exceed the smallest of 0.1 m the disposable head or 0.5 m. (1) The computation of the ultimate capacity under full bore flow has been verified by testing. 7.5 The designer may vary the pipework sizing, layout, or flow to each outlet, or incorporate orifice plates to achieve an acceptable installation. Orifice plates should not be used in gutter outlets. 7.6 An approximate indication of the pipe sizes required can be made using a manual dimensioning procedure detailed in the UV-System Technical Manual. 7.7 The maximum permitted flow through an outlet is 12 s 1 and 24 s 1 for 53 mm and 69 mm diameter outlets, respectively (see Figure 2). 9 Roof/gutter design 9.1 The roof must be designed to allow rain-water to flow freely to the outlets. 9.2 The water depth around the outlet when the system is operating at its maximum flow rate (full bore flow) may be estimated from Figure The maximum water depth on the roof or in the gutter must be estimated in accordance with BS 6367 : The water loading on the roof caused by the water depth calculated in accordance with BS 6367 : 1983 must not exceed the allowable roof loading. 9.5 It is recommended that in accordance with BS 6367 : 1983 the roof and/or gutter design incorporate a built-in overflow facility. The roof must be designed to hold water up to this level should the design rainfall be exceeded or unexpected blockages occur. 10 Performance of joints 10.1 The performance of the joint to the pipework system is dependent on the pipework system adopted. Conventional jointing techniques using independently approved products should provide satisfactory performance (see section 4.4) The performance of the joint between the outlet and the roof material is dependent on the installation. However, conventional jointing techniques for roofs constructed of similar materials applied correctly should give satisfactory performance. 8 Strength The UV-System outlets have adequate strength to resist loads associated with installation and subsequent use. The grating remained intact after applying a load of 1.25 kn through a 100 mm diameter rubber-faced loading plate (ie accidental pedestrian load). 11 Flow characteristics When the system is operating at its design intensity, the high velocity of the water will ensure the system is self-cleansing. Self-cleansing can also occur at rainfalls as low as 50% of the design intensity. At rainfalls less than this the UV-System will operate under vented gravity flow conditions. Figure 2 Flow against depth of water at the outlet (at full bore flow) 80 UV53 UV69 depth of water around outlet (mm) f t r 40 air baf le diame e flow through outlet (litres/second) 3

4 12 Resistance to chemicals The performance of the UV-System outlets will be unaffected by the types and quantities of chemicals associated with rain-water. Figure 3 Roof outlets in single ply membranes 13 Resistance to blockage The high velocities at which the water flows through the pipework, together with the design of the UV- System outlets, reduce the risk of blockages [see also sections 7.4 (a), 11 and 16]. 14 Behaviour in relation to fire The bodies of the UV-System outlets will not affect the overall fire resistance of the roof in which they are installed. single ply membrane hole in membrane 145 mm diameter clamp stud min 15 Thermal insulation Outlets can be supplied with moulded foamed polyethylene insulation fitted to the underside. It may be desirable in some situations to provide additional insulation and to insulate the pipework to prevent condensation. This will depend on the relative humidity and the temperature. t 2 mm in gutter EPDM seal 16 Maintenance Periodic inspection in accordance with BS 6367 : 1983, Clause 18.1, should be carried out to ensure that the outlets are free from gravel, leaves and other debris which could impair the performance of the system. Maintenance is the responsibility of the owner. 17 Durability The materials used for the manufacture of the outlets are highly durable and when installed correctly will have an effective life equivalent to, or in excess of, the roof in which they are installed. Installation 18 General 18.1 The design of the layout of the roof outlets should be in accordance with the recommendations given in BS 6367 : UV-System roof outlets should be placed at the roof low points to allow efficient flow of water to the outlets The system must be installed exactly in accordance with the design. Small differences to pipework length/diameter can significantly affect the performance of the system. 19 Procedure 19.1 An appropriately sized hole must be formed or cut in the roof structure or gutter to accommodate the outlet. The outlet must be secured to the roof structure (see Figure 3). 4 insulation (optional) 500 x 500 x 0.5 copper flange bonded between asphalt layers eight 6.3 mm diameter stainless steel self-tapping/drilling screws with sealing washers hole in gutter 190 mm diameter in built-up membranes in mastic asphalt membranes final layer (maximum 4 layers) second layer do not clamp first layer if perforated final asphalt layer EPDM sealing ring first asphalt layer temporary galvanized steel/asphalt barrier 180 mm diameter approx (optional) all dimensions in millimetres

5 19.2 The BBA has not assessed individual installation details since they will depend on the roof construction Typical installation details not assessed by the BBA but suggested by Sommerhein AB are shown in the UV-System Installation Manual (see also Figure 3). Technical Investigations The following is a summary of the technical investigations carried out on the UV-System for Roof Drainage. 20 Tests Tests were carried out to determine: dimensional accuracy maximum flow capacities watertightness resistance to loading. 21 Other investigations 21.1 An evaluation of existing data was made to assess: resistance to chemicals suitability of materials durability ease of jointing to pipework practicability of installation An investigation was carried out to verify the scientific basis and the correlation with full-scale testing of the computer software used to design the installations The manufacturing processes were examined, including the methods adopted for quality control, and details were obtained of the quality and composition of the materials used. Bibliography BS 5572 : 1994 Code of practice for sanitary pipework BS 6367 : 1983 Code of practice for drainage of roofs and paved areas ISO 9001 : 1987 Quality systems Model for quality assurance in design/development, production, installation and servicing. 5

6 Conditions of Certification 22 Conditions 22.1 Where reference is made in this Certificate to any Act of Parliament, Regulation made thereunder, Statutory Instrument, Code of Practice, British Standard, manufacturer s instruction or similar publication, it shall be construed as reference to such publication in the form in which it is in force at the date of this Certificate The quality of materials and the method of manufacture have been examined and found satisfactory by the BBA and must be maintained to this standard during the period of validity of this Certificate. This Certificate will remain valid for an unlimited period provided: (a) the specification of the product is unchanged; and (b) the manufacturer continues to have the product checked by the BBA This Certificate will apply only to the product that is installed, used and maintained as set out in this Certificate In granting this Certificate, the BBA makes no representation as to: (a) the presence or absence of patent or similar rights subsisting in the product; and (b) the legal right of Sommerhein AB to market, install or maintain the product; and (c) the nature of individual installations of the product, including methods and workmanship It should be noted that any recommendations relating to the safe use of this product which are contained or referred to in this Certificate are the minimum standards required to be met when the product is used. They do not purport in any way to restate the requirements of the Health & Safety at Work etc Act 1974, or of any other statutory or Common Law duties of care, or of any duty of care which exist at the date of this Certificate or in the future; nor is conformity with such recommendations to be taken as satisfying the requirements of the 1974 Act or of any present or future statutory or Common Law duties of care. In granting this Certificate, the BBA does not accept responsibility to any person or body for any loss or damage, including personal injury, arising as a direct or indirect result of the use of this product. In the opinion of the British Board of Agrément, the UV-System for Roof Drainage is fit for its intended use provided it is installed, used and maintained as set out in this Certificate. Certificate No 95/3179 is accordingly awarded to Sommerhein AB. On behalf of the British Board of Agrément Date of issue: 23rd January 1996 Director British Board of Agrément P O Box No 195, Bucknalls Lane Garston, Watford, Herts WD2 7NG Fax: mail@bba.star.co.uk For technical or additional information, tel: For information about Agrément Certificate validity and scope, tel: Hotline: