Slab Construction Quality Check Procedure
Standard operating procedure for slab construction ensuring structural integrity, durability, and serviceability through proper inspection and testing methods in accordance with Indian Standards (IS Codes).
Structure Type: RCC Slab
Quality Priority: High
Validity: All Projects
To establish a comprehensive quality control procedure for Slab Construction, ensuring structural integrity, durability, and serviceability through proper inspection and testing methods in accordance with Indian Standards (IS Codes).
- Ensure formwork material (plywood, steel, etc.) is as per IS 14687:1999
- Check formwork dimensions, levels, and alignment as per drawings
- Ensure formwork is clean, oiled, and tightly fixed to prevent leakage
- Provide adequate supports (props, bracings, and scaffolding) to avoid deflection
- Check for proper camber (if required) to counteract deflections
- Verify formwork joints are tight and sealed to prevent grout loss
- Check formwork surface is smooth to achieve required finish
IS 14687:1999
IS 1200: Part 5-1982
- Verify diameter, spacing, and number of bars as per structural drawings
- Ensure cover blocks (20–30mm) are provided for proper cover
- Check binding wire is used properly for securing bars
- Verify lap length and anchorage as per IS 2502:1963
- Ensure reinforcement is free from rust, oil, and dirt
- Check for extra reinforcement around openings, cantilevers, and load-bearing areas
- Verify main reinforcement and distribution steel placement
- Check cranked bars at support points for proper bending
- Ensure proper positioning of top and bottom steel mats
IS 456:2000
IS 2502:1963
IS 1786:2008
- Ensure provisions for electrical conduits, pipes, and openings are made before casting
- Check that conduits are properly secured and do not affect reinforcement positioning
- Verify alignment of openings with architectural drawings
- Ensure proper shuttering around openings to maintain shape
- Check that openings don't exceed 1/3 of slab depth without additional reinforcement
- Verify trimmer bars around large openings
IS 456:2000
- Check level of slab formwork using water level or laser level
- Ensure proper slope for drainage where required (bathrooms, balconies)
- Verify thickness markings are consistent throughout the slab area
- Check edge formwork for proper alignment and stability
- Verify soffit level of slab matches structural drawings
- Check props are properly shimmed and wedged
IS 456:2000
- Verify adequate shoring and bracing as per IS 3764:1992
- Check working platforms and safety railings are in place
- Ensure props are properly sized for the load they will carry
- Verify foundation of props is adequate and level
- Check horizontal and diagonal bracing between props
- Ensure access arrangements for concrete placement
IS 3764:1992
IS 14687:1999
- Ensure approved concrete mix (e.g., M20, M25, M30) is used as per IS 10262:2019
- Perform slump test (target 75–125mm for slabs) as per IS 1199:1959
- Check for segregation and bleeding in the concrete mix
- Ensure no extra water is added on-site, which may weaken the mix
- Verify concrete temperature is within specified limits
- Check concrete delivery time from batching plant
IS 10262:2019
IS 456:2000
IS 1199:1959
- Ensure concrete is placed within 30 minutes of mixing
- Avoid free fall greater than 1.5m to prevent segregation
- Use mechanical vibrators properly to compact concrete and remove air voids
- Avoid over-vibration, which may lead to segregation and weak zones
- Ensure concrete is placed continuously without cold joints
- Check vibrator insertion depth and spacing
- Ensure proper consolidation around reinforcement
IS 4925:2004
IS 456:2000
- Ensure slab level matches approved structural drawings
- Use leveling instruments to maintain an even surface
- Properly finish slab using wooden or steel trowels to achieve the required texture
- Provide proper slope (if required) for drainage purposes
- Check levels at regular intervals during finishing
- Ensure thickness tolerance is maintained (±10mm)
- Check for proper surface finish as per specification
IS 456:2000
- Take concrete cube samples as per IS 516:1959 (minimum 6 cubes per 100 cum)
- Check concrete doesn't displace reinforcement during placement
- Ensure no formwork movement or bulging during pouring
- Monitor weather conditions and take protective measures if needed
- Check for proper consolidation at construction joints
- Verify no honeycombing or voids formation
IS 516:1959
IS 456:2000