Deshuttering in Construction – Slab & Beam De-Centering Procedure

🔹 Introduction

Deshuttering (also called decentring or formwork removal) is a crucial activity in RCC construction. It refers to the removal of shuttering/formwork after the concrete has gained sufficient strength. Proper Deshuttering ensures structural safety, avoids cracks, and maintains the designed shape and finish.




🔹 Important IS Code Reference

According to IS 456:2000 (Clause 11.3.1) – the time for Deshuttering depends on concrete strength, span, type of member, temperature, and curing.

🔹 General Time for Deshuttering (As per IS 456:2000)

  • Vertical Formwork (Columns, Walls, Sides of Beams): 16–24 hours
  • Soffit Formwork (Slabs, Beams):
    • Slabs (props left under) → 3 days
    • Beams (props left under) → 7 days
  • Removal of Props:
    • Slabs (up to 4.5 m span) → 7 days
    • Slabs (over 4.5 m span) → 14 days
    • Beams & Arches (up to 6 m span) → 14 days
    • Beams & Arches (over 6 m span) → 21 days

🔹 Deshuttering Procedure

  1. Check Concrete Strength → Ensure minimum curing time has passed.
  2. Start with Non-Load Bearing Shuttering → Remove side shutters of beams/columns first.
  3. Remove Props Gradually → Never remove all props at once; remove alternately to avoid shock load.
  4. Maintain Safety → Workers should use safety gear, and no sudden hammering should be done.
  5. Curing After Deshuttering → Continue curing exposed concrete for at least 7 days.

🔹 Quality & Safety Points

✔ Always follow IS code guidelines.
✔ Check proper line, level, and surface finish after shutter removal.
✔ Never deshutter early; it may cause cracks, sagging, or even failure.
✔ Remove formwork carefully to avoid damaging edges & corners.

🔹 Final Note

Deshuttering is not just about removing shuttering material—it’s about ensuring that the RCC structure has achieved enough strength to carry its own load safely. A proper schedule, skilled supervision, and careful removal make the process successful.


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