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240 DURABILITY
• Concrete: Proprietary to BS 8500
- Conformity: To BS 8600-2.
- Identity: Contractor's choice.
- Additional requirements: site specific.
- Exposure class to BS 8500: site specific.
Submit: Proof that the concrete conforms to the recommendations of BS 8500-1
A5.

261 COVER WHEN USING NATURAL STONE FACING
• Natural stone facing qualifying thickness (minimum): 25 mm.
• Nominal minimum concrete cover to exposed face of panel: 20mm.

270 DIMENSIONAL COORDINATION
• Detailing cladding: Comply with the requirements for accuracy in manufacture
and erection, and accommodate deviations in support structure.
• Fixings/ fasteners: Select to give sufficient three dimensional adjustment.
• Proposals to achieve required tolerances: Submit.

MAKING CONCRETE

310 CONCRETE MIXES GENERALLY
• Production of concrete: To BS 8500 and BS EN 206-1.
• Chloride ion content of mix constituents: Not to exceed 0.4% of weight of cement.
• Admixtures containing calcium chloride: Not allowed.
• Sampling rate for compressive strength testing: Not less than one sample for each
day of use.

330 MIXES FOR VISIBLE FACES
• Constituent materials and mix design: To remain constant for each finish type.
• Panel colour and appearance: To be consistent for each finish type.
• Aggregates: To be of consistent colour, free of deleterious materials that cause
popping and staining.
- Origin: Single source for each finish type having sufficient quantity for whole
contract.

MANUFACTURE

420 MANUFACTURING ACCURACY
• Standard: To BS 8297, table 11 and to allow compliance with clause 630.

430 FIXINGS
• Materials generally: Nonferrous metal.
- Stainless steel: Austenitic in accordance with BS 8297, clause 4.3.3.1.
- Allowable alternative: Galvanized steel when located away from external faces
or edges.
• Lifting devices: Mild steel permitted when mortar cover will provide the same
protection required for reinforcement in the panel.
• Bimetallic corrosion and staining: Prevent by appropriate selection and use of
materials.

RotF generic (intermediate) NBS 2014 6118-AEW-XX-XX-NBS-A-01