The Cdb Premium Roofing Slate range is available in a plain surface in sizes 600x300mm and 500x250mm. The CdB Premium range is manufactured to the highest specifications by Comptoir du Batiment in co-operation with Europe’s leading fibre cement producer. CdB roofing slates are composed of Portland cement, natural and synthetic fibres, additives and water. Manufactured using the traditional Hatsjeck lamination method. The sheets are fully compressed to a monolithic flat product. After a period of curing, the sheets are cut and a double coating of paint is applied. The undersides of the slates are treated with a clear acrylic.
Performance Characteristics
CdB Premium slates are manufactured to BS EN 492, 1994; Fibre cement slates and their fittings for roofing, product specification and test method.
The CdB Standard slate is approved for use by the City of Birmingham. In accordance with BS EN 492 and the requirements of the City of Birmingham, CdB on average marks one in every five slates with a manufacturing code as follows: CdB, A, NT, K, Date, Time.
CdB indicates the brand
A indicates the class as specified in BS EN 492
NT indicates new technology i.e. non asbestos
K indicates production site i.e. Kapelle op den Bos
Date & Time indicates production date & time
Handling, Storage & Working Precautions.
Precautions must be taken to prevent the level of dust released in the air to the minimum reasonable practicable level. Whenever possible cutting, sawing and drilling should be carried out in the open air. Avoid breaking the product unnecessarily. For further handling and working precautions please refer to our Health & Safety Data Sheet.
General Design Considerations
CdB Premium slates when fixed to BS5534 Part1: 1997 Design will have adequate resistance to wind loads, wind uplift and rain penetration under most conditions. The specifier should check the annual driving rain index in BS5534 to decide if the area in which the slates are being laid is in a moderate or severe exposure area.
Technical Specification
Standard Slates
Slate Size 600mm x 300mm
Holed 90/110mm lap
Weight per 1000 1555kgs
No per pallet 1008
Slate Size 500mm x250mm
Holed 90/110mm lap
Weight per 1000 1080kgs
No per pallet 16000
Sitework
The slates are delivered on pallets of approximately 1700kg. The pallets must be stored in a dry place. On site the slates should be clear of the ground, the polythene cover split and the stack covered with tarpaulin.
Fixing
The slates should be laid in accordance with the code of practice for slating and tiling BS5534: Part1 1997 and BS8000 Workmanship on building sites Part6 1990. CdB slates are easily workable with normal slater’s tools. Each slate should be fixed with two 30mm copper nails and one copper disc rivet through the pre-holed positions. The slates should never be nailed too tightly. A 4mm (approx) gap should be left between adjoining slates.
Underlay
Protex roofing felt should be used or similar product to BS747: 1994. The underlay should be draped over rafters, or fully supported on boarding. It should allow any moisture to drain and should extend over the tilting piece, fascia board and into the eaves gutter.
Battens
Sizes are recommended in BS5534 for pitched roofs and vertical cladding. Harris recommends the minimum batten size for a 450mm span to be 38mm wide by 25mm deep and for a 600mm span to be 50mm wide by 25mm deep.
Leadwork
Any lead used should be treated with patination oil as it is fixed. If patination oil is not used it could cause unsightly staining to the roof slates.
Ventilation
Adequate ventilation is required for all slate roofs. Ventilation provides the following benefits: Prolonged aesthetic appearance. Avoidance of condensation, resulting in superior insulation performance. Long term protection of roof structure. Harris Slate & Stone have a full range of ventilation products available. See our ventilation data sheet for full details. Accessories A range of GRC ridge tiles are available to suit most roof applications. See separate data sheets for full details.
Accessories
A range of GRC ridge tiles are available to suit most roof applications. See the roofing accessories section for further details.
