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F31 Precast concrete sills/ lintels/ copings/ features

TYPES OF COMPONENT

105 PRECASTcopings, cornice, lintols, cills and the like
• Concrete: Components manufacturer's 'proprietary' concrete.
- Identity: Manufacturer's mix reference.
• Conformity: To BS 8500-2 and the recommendations of
BS 8500-1 Annex A4 for the specified exposure class.
- Evidence: Submit third party certification from a UKAS accredited laboratory.
• Exposure class: as required - site specific.
- Strength class (cylinder/ cube): Manufacturer's choice.
• Reinforced components: Submit proposals for type of reinforcement and cover.
• Matching sample for finish to visible faces: As reference sample.
• Other requirements: site specific.

140 CONCEALED PRECAST LINTELS
• Concrete: designated to BS 8500-2: Minimum RC30.
- Aggregate (maximum) size: 20 mm.
• Configuration:
- Clear span up to 900 mm:
Section: 140 mm deep x width of wall.
Bearing: 150 mm at both ends.
Reinforcement: One 12 mm carbon steel bar for each 105 mm of wall thickness.
- Clear span 900 mm to 1800 mm:
Section: 215 mm deep x width of wall.
Bearing: 225 mm at both ends.
Reinforcement: One 16 mm carbon steel bar for each 105 mm of wall thickness.
• Cover to reinforcement: 20 mm minimum.

150 CONCEALED PRECAST PADSTONES
• Concrete: Designated to BS 8500-2: Minimum RC30.
- Aggregate size (maximum): 20 mm.
• Other requirements: site specific .

GENERAL REQUIREMENTS

210 MOULDS
• Permissible fabrication and operating tolerances: Length 0 to +6 mm, other
dimensions ±3 mm.

220 CONCRETE GENERALLY
• Specification: To BS 8500-2 and BS EN 206-1.
• Producer: Currently certified by a body accredited by UKAS to BS EN 45011 for
product conformity certification of ready-mixed concrete.
• Chloride class of concrete: Excluding SPRC: C 10.40
- Using SRPC: C1 0.20.
- Reinforced and heat cured: C1 0.10.
- Prestressed: C1 0.10.
• Admixtures containing calcium chloride: Not allowed.

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